html Assessment of walleye pollock in the eastern Bering Sea

Assessment of walleye pollock in the eastern Bering Sea

Affiliation

James Ianelli

Alaska Fisheries Science Center, NOAA Fisheries

Sophia Wassermann

Abigail McCarthy

Carey McGilliard

Elizabeth Siddon

Kalei Shotwell

Grant Adams

Nathan Lauffenburger

NoteSI-assisted development

Tools assisted data processing, code execution, figure preparation and report writing under author direction. The authors retain responsibility for the scientific content, analyses, interpretations and conclusions.

NoteSuggested citation

Ianelli, J., S. Wassermann, A. McCarthy, C. McGilliard, E. Siddon, K. Shotwell, G. Adams, and N. Lauffenburger. 2026. 2026 Assessment of Eastern Bering Sea Walleye Pollock. https://files.npfmc.org/SAFE/2026/EBSpollock.pdf.

1 Executive summary

The last full EBS pollock assessment was completed in 2024 (Ianelli et al. 2024). A catch report was prepared in 2025 (Alaska Fisheries Science Center, National Marine Fisheries Service 2025). Changes in this assessment are described relative to 2024.

This executive summary presents Model 26.0 (Rceattle), the base model for this assessment and its Tier 3 harvest recommendations. Model 23.0 (ADMB), accepted in 2024, provides the comparison with the previous assessment.

1.1 Changes in assessment inputs

Catch, fishery age compositions, survey indices and age compositions, and weight-at-age schedules have been updated since 2024. Section 2.1.1 describes the years, sources and data treatments.

1.2 Changes in assessment methods

Model 26.0 implements the age-structured assessment in Rceattle and uses weight-at-age schedules estimated by a separate random-effects model. Section 2.1.2 describes these changes from Model 23.0.

1.3 Summary of results

Estimated total biomass in 2026 is 12.162 million t (approximate 95% log-scale Wald confidence interval 9.534–15.515 million t). Female spawning biomass (SSB) is 3.057 million t (2.489–3.754 million t, using the same interval method). The largest fishing mortality rate among ages is 0.3 per year.

Scenario 2, the expected-catch projection scenario, assumes catches of 1.375 million t in each of 2027 and 2028, equal to the specified 2027 annual TAC. The projections use mean 2023–2025 fishery selectivity, fixed biological inputs and recruitment equal to the fitted 1978–2023 mean (Section 7).

The advice table compares the 2025–2026 recommendations from the 2024 assessment with this assessment’s 2027–2028 recommendations. Projected female spawning biomass and age 3+ biomass use Scenario 2 with the assumed catches above.

The final specifications for 2026 and 2027, issued in the absence of a 2025 stock assessment, specified the Bering Sea subarea pollock OFL at 2,496,000 t and ABC at 2,036,000 t; specified annual TAC is 1,375,000 t. These are the adopted specifications, separate from the recommendations from this assessment.

The stock is above MSST in 2026 and is not approaching an overfished condition (Section 9). All risk categories are Level 1, supporting maximum ABC (Section 8).

Model 26.0 advice from revised fits
Quantity
As estimated or specified in 2024 for:
Primary baseline Model 26.0 for:
2025 2026 2027 2028
Natural mortality (annual rate, ages 3+) 0.300 0.300 0.300 0.300
Tier and sub-tier 3a 3a 3a 3a
Projected total biomass (ages 3+, t) 8,526,000 8,075,000 11,270,000 12,367,000
Projected female spawning biomass (t) 3,118,000 3,342,000 3,198,000 3,394,000
B100% (t) 5,902,000 5,902,000 6,158,000 6,158,000
B40% (t) 2,361,000 2,361,000 2,463,000 2,463,000
B35% (t) 2,066,000 2,066,000 2,155,000 2,155,000
F_OFL (annual rate) 0.513 0.513 0.658 0.658
Maximum F_ABC (annual rate) 0.394 0.394 0.513 0.513
Recommended F_ABC (annual rate) 0.394 0.394 0.513 0.513
OFL (t) 2,957,000 2,496,000 2,328,000 2,422,000
Maximum ABC (t) 2,417,000 2,036,000 1,896,000 1,968,000
Recommended ABC (t) 2,417,000 2,036,000 1,896,000 1,968,000
Historical source: December 2024 SAFE, Executive Summary, Tier 3 version, p. 4; B40% is printed in section 7.2, p. 35.
2027–2028 projections assume catch of 1,375,000 t in each year, mean 2023–2025 selectivity and fixed biological inputs. Total biomass covers ages 3+ at the start of the year. F_OFL and maximum F_ABC are the fully selected F35% and F40% rates. Biomass and catch are rounded to the nearest 1,000 t.
Spawning biomass exceeds B40% in both years, placing the stock in Tier 3a. All risk categories are Level 1, supporting the maximum ABC. Recruitment is fixed at the fitted 1978–2023 mean; these projections show point estimates. Adopted catch specifications are reported separately.
Model 26.0 stock-status summary. The 2025–2026 columns report status for 2025 and 2026; historical determinations are from the 2024 assessment.
Status
As determined in 2024 for:
As determined this year for:
2023 2024 2025 2026
Overfishing No n/a No n/a
Overfished n/a No n/a No
Approaching overfished n/a No n/a No
Historical determinations are from the December 2024 EBS pollock SAFE, Executive Summary, p. 4.
Assessment conclusions are separate from final NMFS determinations. Updated 2025 catch (1,326,215.61 t) is below its 2,957,000-t OFL. For Model 26.0, 2026 spawning biomass (3.057 million t) and Alternative 7 biomass in 2028 (3.123 million t) both exceed B35% (2.155 million t), supporting the two 2026 “No” entries. Section 9 describes the status tests. Each two-year column pair reports overfishing for the earlier catch year and stock status for the later assessment year; cells outside those year-specific determinations are marked n/a. NMFS issues the final status determinations.

1.4 SSC and Plan Team requests

The September 2026 Plan Team requested the following work:

  • Present Model 26.0 for management use and Model 23.0 for continuity; both are compared in this assessment.
  • Examine age-1 BTS selectivity and the influence of BTS variability on retrospective patterns. Additional selectivity and data-influence tests are outside the scope of this assessment.
  • Extend the simulation self-test and examine retrospective patterns in time-varying selectivity. The completed simulation experiment and its limitations are described in Section 6.3.1.
  • Present retrospective results for Models 23.0 and 26.0 side by side. Matched runs were completed and compared; both models showed similar spawning-biomass retrospective patterns (Appendix A).
  • Document age-composition weighting and evaluate residual patterns. Selected sample sizes, one-step-ahead residuals and Francis comparisons are presented in the assessment.
  • Continue development of the Ecosystem and Socioeconomic Profile; we developed a draft using AI to compile and coordinate information from disparate sources (Appendix B).

Earlier SSC requests address model development, uncertainty, survey treatment and composition weighting. The individual requests and responses are presented in Appendix A.

2 Introduction

2.1 General

Walleye pollock (Gadus chalcogrammus; hereafter referred to as pollock) are broadly distributed throughout the North Pacific with the largest concentrations found in the eastern Bering Sea (EBS). Also known as Alaska pollock, this species continues to play important roles ecologically and economically.

2.1.1 Changes in assessment inputs

The 2026 assessment updates the accepted December 2024 assessment; the 2025 document was a catch report. Updated inputs include annual catches from 1991 onward, fishery age compositions for 2024–2025, BTS indices and age compositions for 2025–2026, the 2026 ATS index and provisional age composition, and AVO indices through 2026. Historical BTS estimates were also revised. Spatiotemporal survey estimation continues the approach adopted in 2024; the current biomass-index and abundance-at-age products use sdmTMB (Anderson et al. 2025) and tinyVAST (Thorson et al. 2025), respectively.

The 2024–2025 fishery age compositions use year-specific FT-NIRS-to-traditional-microscopic-age conversions, with likelihood sample sizes of 578 and 530. The provisional 2026 ATS age composition applies the BTS age–length key to ATS lengths; FT-NIRS ages from the ATS samples are expected in 2027.

Fishery weight-at-age retains the fixed 1964–1990 schedule and annual observation means for 1991–2025. A separate random-effects model fitted to fishery and BTS weights through 2025 supplies 2026 predictions and 2027–2028 forecasts; its fit omits the 2026 BTS observations. Population weights use BTS means through 2026, including revised historical estimates. Spawning weights at ages 3–15+ use fitted 2024–2025 A-season weights and a 2026 projection, retaining the previous ages 1–2 schedule. Section 4 and Appendix G and Appendix H describe the data treatments and their uncertainty.

2.1.2 Changes in assessment methods

The main assessment-method change is the transition from the ADMB implementation of Model 23.0 to the Rceattle implementation of Model 26.0. Weight-at-age is estimated in a separate random-effects model and used as fixed schedules, whereas Model 23.0 estimates cohort and year effects within the assessment. Model 26.0 uncertainty therefore conditions on the estimated weights. Natural mortality and catchability assumptions retain the previous treatment. The configuration comparisons, diagnostics and sensitivities evaluate the effects of the data updates and implementation change (Section 5, Section 6 and Appendix I).

2.2 Review of Life History

In the EBS, pollock generally spawn during March–May and in relatively localized regions during specific periods (Bailey 2000). Generally spawning begins nearshore north of Unimak Island in March and April and later near the Pribilof Islands (Bacheler et al. (2010)). Females spawn in batches with up to 10 batches of eggs per female per year (during the peak spawning period). Eggs and larvae of EBS pollock are planktonic for a period of about 90 days and appear to be sensitive to environmental conditions. These conditions likely affect their dispersal into favorable areas (for subsequent separation from predators) and also affect general food requirements for over-wintering survival (Gann et al. (2015), Heintz et al. (2013), Hunt Jr. et al. (2011), Ciannelli et al. (2004)). Duffy-Anderson et al. (2016) provide a review of the early life history of EBS pollock.

Throughout their range juvenile pollock feed on a variety of planktonic crustaceans, including calanoid copepods and euphausiids. In the EBS shelf region, one-year-old pollock are found throughout the water column, but also commonly occur in the NMFS bottom trawl survey. Ages 2 and 3 year old pollock are rarely caught in summer bottom trawl survey gear and are more common in the midwater zone as detected by mid-water acoustic trawl surveys. Younger pollock are generally found in the more northern parts of the survey area and appear to move to the southeast as they age (Buckley et al. (2009)). Euphausiids, principally Thysanoessa inermis and T. raschii, are among the most important prey items for pollock in the Bering Sea (Livingston (1991); Lang et al. (2000); Brodeur et al. (2002); Ciannelli et al. (2004); Lang et al. (2005)). Pollock diets become more piscivorous with age, and cannibalism has been commonly observed in this region. However, Buckley et al. (2015) showed that spatial patterns of pollock foraging, including cannibalism, vary with the size of the foraging pollock. For example, pollock in the northern shelf region between the 100 and 200 m isobaths (closest to the shelf break) tend to be more piscivorous than pollock in shallow nearshore areas.

2.3 Stock structure

Stock structure for EBS pollock was evaluated in Ianelli et al. (2015). In that review past work on genetics (e.g., Bailey et al. (1999), Canino et al. (2005)) provided insight on genetic differentiation. The investigation also compared synchrony in year-classes and growth patterns by region. Pollock samples from areas including Zhemchug Canyon, Japan, Prince William Sound, Bogoslof, Shelikof, and the northern Bering Sea were processed and results presented in Ianelli et al. (2021). Genetics research at the AFSC (Ianelli et al. 2023) indicated that genetic groups mostly aligned with current stock-management delineations. The Aleutian Islands and Bogoslof stocks showed subtle differentiation from the Gulf of Alaska stocks.

3 Fishery and management history

Directed foreign fishing began in 1964. US vessels entered the fishery in 1980, and it became fully domestic by 1988. The domestic observer program formally began in 1990; later monitoring developments include electronic monitoring on participating catcher vessels and biological sampling during offloading (Ianelli et al. 2024). The directed fishery primarily uses pelagic trawl gear, with inshore, catcher/processor and mothership sectors. The historical catch and adopted harvest-limit series is continued through 2026 in Table 1.

Updated reported catches are 1,311,261 t in 2024 (2025 catch report) and 1,326,193 t in 2025 (National Marine Fisheries Service Alaska Region 2026b). The catch table reports two 2026 values: reported catch of 1,297,206 t through October 17 (National Marine Fisheries Service Alaska Region 2026a) and the annual catch estimate of 1,312,504.58 t used in this assessment.

For 2026, the adopted ABC and OFL are 2,036,000 and 2,496,000 t. The Bering Sea subarea TAC increased from 1,375,000 to 1,389,500 t after inseason reallocations. The August allocations included 139,400 t for Community Development Quota (CDQ) directed fishing and 46,000 t for incidental catch. Bering Sea catch totals include CDQ directed catch and incidental catch, including incidental CDQ catch. Bogoslof and Aleutian Islands catches are reported separately (National Marine Fisheries Service 2026a, 2026c).

The directed pollock allowance is allocated 45% to the A season (January 20–June 10) and 55% to the B season (June 10–November 1). The non-CDQ allowance is divided among the inshore (50%), catcher/processor (40%) and mothership (10%) sectors. In the Steller sea lion conservation area, each sector may catch up to 28% of its annual directed allowance before noon April 1 (National Marine Fisheries Service 2026a). The Winter Herring Savings Area (58–60° N, 172–175° W) is closed to directed pollock trawling, including CDQ fishing, from September 30, 2026, to March 1, 2027 (National Marine Fisheries Service 2026b).

Area restrictions, allocations, monitoring, and incentives are used to reduce prohibited species catch in the EBS pollock fishery. Table 2 summarizes major management changes. Industry cooperatives use rolling-hotspot closures to move fishing away from areas of high salmon bycatch. These voluntary programs began for chum salmon in 2001 and Chinook salmon in 2002. Amendment 84, implemented in 2007, allowed participating vessels to use approved intercooperative bycatch-reduction agreements in place of specified fixed salmon-area closures (National Marine Fisheries Service 2007, 2023).

Amendment 91 established Chinook salmon bycatch limits and incentives to reduce bycatch while allowing the pollock TAC to be harvested. Implemented in the 2011 fishery, it combined a 60,000-fish annual prohibited species catch (PSC) limit with incentive plan agreements and a 47,591-fish performance standard. A sector that exceeds its share of the standard in three of seven consecutive years receives a lower allocation in all subsequent years. Amendment 110, implemented in 2016, strengthened Chinook and chum avoidance and tied Chinook limits to salmon returns in western Alaska. When the State of Alaska’s index for the Kuskokwim, Unalakleet and Upper Yukon systems is 250,000 fish or less, the following year’s PSC limit and performance standard fall to 45,000 and 33,318 fish, respectively. The index first applied to the 2017 fishery (National Marine Fisheries Service 2010, 2016).

NOAA Fisheries’ North Pacific Groundfish and Halibut Observer Program provides the salmon counts used to monitor PSC limits in the Bering Sea pollock fishery. Regulations require vessels to retain salmon until observers can count them at at-sea processors or during offloading. Catcher vessels carry an observer or an electronic monitoring (EM) system, and shoreside observers count salmon in deliveries (National Marine Fisheries Service Alaska Regional Office 2025). The Alaska Fisheries Science Center’s Genetics Program analyzes tissue samples collected by observers to identify the salmon stocks caught as bycatch. These stock-composition estimates help assess impacts on salmon populations and guide avoidance measures (NOAA Fisheries salmon bycatch monitoring). Genetic sampling of the 2015 Chinook bycatch is described by (Guthrie et al. 2017).

3.1 Fishery conditions

The A-season fishery targets pre-spawning pollock and supports roe production. Fishing has historically concentrated north and west of Unimak Island and along the shelf toward the Pribilof Islands, with access affected by ice, weather and fish distribution. The summer–fall B-season fishery follows changes in fish availability across the shelf. Salmon-avoidance measures and vessel choices also influence where fishing occurs. Available observer data suggest good fishing conditions in the 2026 A season; later in the B season fishing moved farther north and pollock of desirable sizes were less available.

Catch by area and season is summarized in Table 3. The catch as of October 17, 2026, was 1,267,543 t: 604,041 t in the A season and 663,501 t in the B season.

Table 4 summarizes annual retained and discarded catch. The 2026 total is 1,312,505 t, including 8,997 t discarded (0.7%).

Nominal pollock catch per tow-hour is generally higher in the A season than in the B season, with A-season peaks in 2019 and 2023 (Figure 1). Species-specific patterns differ: A-season Chinook rates peak in 2006–2007, whereas the chum salmon series has its largest B-season rates in 2005 and 2017. Herring and sablefish each have a pronounced peak in 2020, in the A and B seasons respectively. These are nominal rates for available pollock-dominated EBS hauls, calculated from summed catch and valid tow-hours with panel-specific units.

Estimated catch numbers for both sexes decline to a trough in 2009, rise again during the 2010s and reach their largest annual totals in 2021 (Figure 2). B-season numbers generally exceed A-season numbers within each sex, and female annual catch numbers decline from 1,075.8 million fish in 2023 to 916.7 million in 2025, while male catch numbers decline from 1,218.9 million to 952.6 million. Catch numbers are expressed in thousands of fish.

The cumulative monthly depiction shows whether A-season fishing activity has shifted toward earlier or later months within the year. Cumulative catch through April stays near 40% of annual specified TAC over much of 2000–2017 and near 44% from 2018 onward (Figure 3). In 2026 the cumulative shares are 6.69%, 23.14%, 39.42% and 43.72% at the end of January, February, March and April, respectively. Monthly totals are based on weekly catch reports and the specified annual TAC before quota transfers. These observations cover the first four months of the year; the A season continues through June 10.

As expected, A-season roe production exceeds B-season production throughout the 2000–2026 series (Figure 4). A-season production peaks in 2006 and again in 2019, declines through 2021 and rises from 2022 to 2026. The latest A-season value is 19,092.9 t of roe. The 2025 B-season total is 1,795.8 t; the 2026 total of 406.4 t covers June–October and represents a partial-season estimate.

The broader BSAI fishery’s catch, vessel participation and market context are summarized in the ESP socioeconomic tables.

3.1.1 Recent spatial catch patterns

The seasonal maps compare 2024–2026 using the available catch-location records (Figure 5; Figure 6). A-season maps cover January 20–June 9. B-season maps use June 10–September 18 in every year, matching the 2026 data cutoff. Vertical bar heights show catch tons. The rotated, elevated view separates neighboring columns. Each season uses a fixed vertical scale across its three years, with a 10,000-t reference column in each panel. The vertical scales differ between seasons.

A-season fishing remained concentrated on the southeastern shelf, with more catch extending westward in 2025. The share of available observed catch west of 170°W increased from 15% in 2024 to 39% in 2025, then returned to 15% in 2026. The catch-weighted mean latitude changed from 56.07°N to 56.43°N and 56.19°N, respectively. The 2026 pattern therefore shifted back toward the southeastern grounds relative to 2025.

The B-season distribution extended farther north and west in 2025–2026 than in 2024. The share of catch north of 58°N increased from 54% in 2024 to 75% in 2025 and 79% in 2026. The share west of 170°W rose from 76% to about 92% in both later years. Catch-weighted mean latitude was 57.66°N in 2024, 58.56°N in 2025 and 58.52°N in 2026. Thus, the recent northward shift persisted in 2026, while the catch-weighted mean longitude moved eastward relative to 2025, from 174.65°W to 173.26°W.

3.1.2 Fleet dispersion

Fleet dispersion describes how widely separated fishing locations are within a day (Figure 7). Following the 2024 assessment, we calculate the great-circle distance between each unique pair of tows made on the same day, separately for catcher-processors and observed catcher vessels. Distance sums and pair counts are then pooled by year and season. Days with more tow pairs contribute more to the seasonal average. Larger values indicate a more dispersed pattern of observed fishing locations; smaller values indicate greater concentration.

A-season dispersion increased from 47.8 nautical miles in 2024 to 68.8 in 2025, then declined to 36.5 in 2026. This change is consistent with the 2025 westward extension and the more concentrated southeastern pattern in 2026 shown in the catch maps. For B-season records through September 18 in each year, dispersion declined from 78.5 nautical miles in 2024 to 67.8 in 2025 and 56.5 in 2026. Thus, the observed B-season fishing locations became more concentrated even as much of the catch remained farther north than in 2024. A shift in fishing location and a change in spatial spread describe different aspects of fleet behavior.

Changes in the mix of observed vessels, bycatch avoidance and fishing conditions can influence this index, so it should be interpreted together with catch distribution and catch rates.

3.1.3 Seasonal changes in fish size

Mean fish weight is the pollock weight divided by the corresponding fish count. Weight-bin distributions show how the sizes encountered by the fishery change over time (Figure 8).

The dominant A-season mean-weight bin increased from 550 g in 2023 to 600 g in 2024–2025 and 700 g in 2026. For the B season, the dominant bin increased from 450 g in 2023 to 550 g in 2024 and 700 g in 2025, then shifted to 450 g in the available 2026 records. This recent contrast is consistent with the reported difficulty finding larger pollock during the 2026 B season. Changes in these distributions can reflect growth, recruitment, the areas fished and the mixture of vessels represented in the observations.

Weekly displays show how size patterns develop within the A-season and B-season windows (Figure 9; Figure 10).

3.2 Bycatch

Pacific ocean perch (3,995 t) and Pacific cod (3,315 t) were the largest bycatch categories in the pollock fishery in 2025, followed by flathead sole (1,813 t). Preliminary 2026 estimates through October 24 were 2,412 t of Pacific ocean perch, 6,549 t of Pacific cod, and 3,367 t of flathead sole. See Table 6.

Pollock catch in identified non-pollock fisheries declined from 46,996 t in 2024 to 29,263 t in 2025. Rock sole, yellowfin sole, and Pacific cod fisheries accounted for 10,776 t, 8,710 t, and 6,427 t, respectively, in 2025. The preliminary 2026 total through October 31 was 34,729 t; the different cutoffs and partial-year coverage qualify comparisons with the other bycatch tables. See Table 7.

Prohibited-species bycatch is summarized in Table 8. Chinook catches increased from 8,054 fish in 2024 to 19,825 in 2025, and non-Chinook catches increased from 35,152 to 151,457 fish. Halibut mortality rose from 53 to 66 t. Preliminary 2026 catches through October 24 were 15,153 Chinook, 149,468 non-Chinook, and 56 t of halibut mortality.

Jellyfish dominated the selected nontarget-species catch by weight. Estimated jellyfish catch declined from 4,402 t in 2024 to 1,769 t in 2025. Miscellaneous fish contributed 99 t in 2025, with smaller catches in each of the other displayed groups. Preliminary jellyfish catch through October 24, 2026 was 4,418 t. These catch estimates describe fishery encounters and should be interpreted with fishing effort, distribution, and reporting coverage. See Table 9.

4 Data

Fishery catch data begin in 1964, whereas the BTS began in 1982 and the ATS in 1994 for the purposes of this assessment (see the table below). Available fishery age compositions end in 2025 because sample collections are still underway for the 2026 fishing year.

Source Type Years
Fishery Catch biomass 1964–2025; 2026 year to date and projected annual input
Fishery Catch age composition 1964–2025
Fishery Historical trawl CPUE 1965–1976
Bottom-trawl survey Biomass index and age-specific proportions 1982–2019, 2021–2026
Acoustic-trawl survey Biomass index and age-specific proportions 1994, 1996, 1997, 1999, 2000, 2002, 2004, 2006–2010, 2012, 2014, 2016, 2018, 2020, 2022, 2024, 2026
Acoustic vessels of opportunity (AVO) Relative backscatter index 2006–2019, 2021–2026

4.1 Fishery data

4.1.1 Catch

Annual catch rose from about 0.175 million t in 1964 to the series maximum of 1.875 million t in 1972 (Figure 11). Catch subsequently fluctuated, fell to 0.811 and 0.810 million t in 2009 and 2010, respectively, and recovered to 1.326 million t in 2025. The 2026 records total 1.268 million t through October 17 and represent a partial year. Records before 1991 provide annual totals; later records distinguish the A-season and northwest and southeast B-season catches.

The annual assessment catch includes retained and discarded commercial pollock across gears and targets in the Bering Sea, with CDQ counted once and the separately reported Bogoslof and Aleutian Islands catches excluded. The catch update uses the catch estimates for 1991–2026, with pre-1991 model inputs retained. The revised totals are 1,311,260.74 t in 2024, 1,326,215.61 t in 2025 and 1,312,504.58 t in 2026. The 2026 estimate is the annual input selected for this assessment. Explicit Bogoslof (518) and outside-stock area codes are excluded. The 1998 records with blank area codes remain included under their Bering Sea classification. Noncommercial removals remain separately documented in Appendix C.

4.1.2 Age compositions

Fishery catch-at-age estimates for 1964–2025 are summarized in Table 5. Ages 15 and older are pooled as 15+. Where complete annual catch numbers are unavailable, we calculate numbers at age from the assessment proportions, annual fishery weight-at-age and catch biomass.

We estimate fishery age compositions from biological samples collected by at-sea observers and during shore-side offloading. The sampling records include fish measured for length frequencies, paired weight–length measurements, and age estimates (Table 10; Table 11; Table 12). The processing keeps recent unsexed fish separate rather than assigning them to males or females. Within each sex and sampling stratum, we expand length frequencies to the associated catch biomass using mean weight at length. Age–length keys allocate the expanded numbers to ages; we then sum the numbers across strata and sexes and normalize them to give annual proportions (Kimura 1989; Barbeaux et al. 2005; Ianelli et al. 2024). Earlier assessments provide the pre-1991 age compositions. For the 2024–2025 update, the processing strata are January–May across Bering Sea areas, followed by June–December split into northwest (NMFS reporting areas 520 and above) and southeast (areas below 520). The 2024 assessment describes January–June and July–December groups; the current sampling groups use the calendar periods defined above. The new length and age records cover all 12 months.

The linked bootstrap represents variation among sampling units and among length and age observations within those units. Its composition precision estimates inform the selected likelihood sample sizes: 443, 578 and 530 for 2023, 2024 and 2025, respectively. They represent effective information for fitting the annual proportions, rather than numbers of fish measured or aged (Section 4.3.1). The model fits annual sex-combined proportions at ages 1–14 and 15+. Fishery age observations end in 2025.

The 2024–2025 age-estimate data are from pelagic trawl fisheries. For 2025, FT-NIRS predictions from model a00-d3 are expressed on an independent traditional microscopic-ageing (TMA) basis using 668 paired estimates (Appendix G). Within each FT-NIRS age, the paired observations define the proportions assigned to each tester age. These probabilities redistribute the catch-expanded numbers among ages while preserving their total. Source age 13 lacks paired tester observations; its conditional probabilities are the midpoint of the age-12 and age-14 rows. The 2025 source and tester ages range from 2 to 15, and the assessment fits ages 1–14 and 15+. The likelihood uses the selected input sample size of 530. Uncertainty in the conversion key and the age-13 interpolation is additional to the sampling uncertainty represented by that input weight.

The 2024 fishery age composition is expressed on the independent TMA basis using 693 paired reader–tester observations. For source age 13, the key pools TMA-minus-FT-NIRS age offsets from the same year’s source ages 9–12 (34 pairs) and adds those offsets to age 13. Empirical key rows retain their observed probabilities.

4.1.3 Weight-at-age

Mean weight-at-age connects the assessment’s estimates of fish numbers to catch biomass and harvest projections. Seasonal and spatial differences in fish condition and fishery distribution affect these means. Fishery sampling is therefore organized by season and area, with stratum estimates combined using the corresponding catch information. Completed-year observations provide the basis for estimating weights for the observation year and forecasting the weights needed for future catches.

For recent fishery samples, Fourier-transform near-infrared spectroscopy (FT-NIR) of otoliths provides predicted ages. Year-specific paired FT-NIR and traditional morphological ageing (TMA) observations align these predictions with the TMA age basis. Estimated abundance and biomass in each FT-NIR age bin are redistributed using the same conditional tester-age key. Mean weight at a target age is then converted biomass divided by converted abundance. For the 15+ group, biomass and abundance are pooled before taking their ratio. The conversion retains each source bin’s mean weight when allocating it among tester ages. Its reported uncertainty conditions on the selected key; the supported ages and approved tail-allocation rules are documented in Appendix G.

The weight-model approach described in Section 14.5 of the 2024 assessment (Ianelli et al. 2024) links growth within cohorts to annual changes in condition. A smooth mean age pattern defines the typical weight increments. A cohort’s weight in the previous year provides the starting point for the next age, while annual random effects allow variation in starting weight and growth. Observed mean weights and their variances inform this model, separating sampling precision from variability among years. The fitted model supplies predictions for missing observations and forecasts for future years. Model 26.0 uses the resulting weight schedules as fixed biological inputs.

The annual fishery weights in Table 28 retain the historical observational inputs through 2025, with fitted values for missing 2025 ages 13 and 14. The 2026 predictions and 2027–2028 forecasts use the standalone WtAgeRE fit. Ages 1–2 retain the 2024 inputs, the 1964–1990 schedule remains fixed, and the terminal age is 15+.

Cohort growth and annual changes in condition link observed weights to the schedules used for catch and spawning projections. Observed fishery and BTS weights and the selected fishery-scale estimates for 2014–2028 are shown in Figure 23. The forecast follows the 2026 age-3 cohort from 0.368 kg to 0.482 kg at age 4 in 2027 and 0.601 kg at age 5 in 2028. The 2026 biological weight schedules are compared with the selected 2027 catch and spawning projection weights in Figure 35.

4.2 Survey data

4.2.1 Bottom-trawl survey

The AFSC bottom-trawl survey provides indices of pollock abundance and population age structure, complementing the acoustic-trawl survey’s sampling of the midwater component. Historical and recent sampling effort is summarized in Table 13. Annual surveys began in 1979, with standardized gear and methods from 1982 (Ianelli et al. 2024). The 2025 and 2026 observations extend the 42 survey years available for the 2024 assessment to 44 observed years during 1982–2026. The survey was absent in 2020; that year remains a gap in the observation series. The biomass estimates and assessment CVs are listed in Table 14. Availability to bottom-trawl gear varies with age and vertical distribution. Ages 2–3 are often relatively scarce in the catches because juveniles tend to occupy the water column (Monnahan et al. 2021; O’Leary et al. 2022).

Bottom temperature appears to influence the distribution of pollock available to the bottom-trawl survey. The AKsf survey-mapping example (Ianelli 2026) places annual CPUE distributions alongside the 0, 2 and 4 °C bottom-temperature contours for 2018, 2019 and 2021–2026 (Figure 12). High CPUE is concentrated along parts of the western and southern shelf, with several dense patches near the 2 °C contour in 2022, 2024 and 2026. The more extensive warm-water conditions in 2018–2019 contrast with the broader areas of cold bottom water in later panels, while the locations and extent of the pollock concentrations also change.

These patterns suggest that temperature helps structure near-bottom habitat and survey availability, with concentrations often near the margins of colder shelf water. Depth, prey, age composition and vertical movements can also contribute to the pattern. The maps show spatial associations between survey distributions and temperature. Other environmental and biological factors may also contribute. They use locally interpolated, density-dependent-corrected CPUE within survey coverage. The example’s correction version and adoption status are unspecified, so its CPUE surface serves as a descriptive illustration alongside the assessment indices.

The standard EBS survey expanded northwest in 1987. Sampling in the separate NBS region has varied among years, while pollock distribution has shifted between regions. Model-based estimates integrate station observations, including zero catches, across the EBS and NBS and account for spatial and temporal variation (O’Leary et al. 2020). The biomass index uses sdmTMB and abundance at age uses tinyVAST, replacing the earlier VAST implementation. The complete selected abundance-at-age series incorporates historical revisions as well as the recent observations (Table 15). The regional coverage, model specifications, annual covariance and remaining production-source qualifications are described in Appendix H. Estimates for unsampled years are model predictions.

The BTS length distributions show pronounced changes in the sizes represented in the survey (Figure 13). Peaks among small fish and their progression toward larger lengths illustrate cohort growth, while the relative contribution of small and large fish varies among years. These distributions complement the age compositions by showing changes in size directly.

The BTS age compositions show changes in the ages represented in the survey and the progression of cohorts through time (Figure 14). Highlighted bars follow the 1992, 2012 and 2018 year classes through successive ages. The 2012 year class progresses from age 1 in 2013 to age 10 in 2022, while the 2018 year class progresses from age 1 in 2019 to age 8 in 2026. The blank 2020 row marks the gap when the survey was absent.

The age compositions combined traditional age readings and FT-NIRS estimates. We converted the 2026 FT-NIRS estimates to traditional ages using 307 screened paired readings (Appendix G). The conversion preserved total survey abundance and pooled ages 15 and older into the 15+ group.

Spatiotemporal estimation of BTS weight-at-age, adopted in 2022, replaces the earlier conversion of mean length to weight (Indivero et al. 2023). The full BTS-derived weight schedules used for population biomass are presented in Table 16; the compact biological-input summary retains the recent fishery and spawning schedules and fixed biological parameters. We applied the screened 2026 age key consistently to BTS weight-at-age means and their delta-method standard errors, retaining the joint covariance treatment. We used the same key for the provisional ATS abundance and biomass-derived weights, including the weights used to predict the 2026 AVO index. We refitted the standalone random-effects weight-at-age model with the revised BTS means and standard errors under the existing equations, likelihood and source-covariance treatment, preserving fishery observations and the 2025 conversion key. These uncertainty calculations exclude empirical age-key uncertainty. The conversion, weight calculations and assessment use are described in Appendix G.

The missing 2020 survey and subsequent 2021 observation affect interpretation of the time series. Retrospective comparisons describe changes in population estimates as observations accumulate (Section 6.1.5).

4.2.2 Acoustic-trawl survey

The 2026 ATS ages are provisional: we apply the BTS age–length key (ALK) to ATS population length-frequency estimates. FT-NIRS ages from the 2026 ATS samples will be available in 2027.

Acoustic-trawl surveys (ATS) are typically conducted every other year and estimate the off-bottom component of the pollock stock, complementing the annual BTS index of near-bottom pollock. Historical and acoustic-trawl sampling effort is summarized in Table 17. The 2026 collections retain their regional scope, while unavailable direct age counts remain NA.

Estimated pollock biomass for the EBS shelf has averaged about 3.202 million t since 1994, when the revised time series begins (Table 18). The revised estimates include the water column down to 0.5 m above the seafloor; the historical midwater index extended to 3 m above the seafloor. Low recruitment during the relatively warm early 2000s was subsequently reflected in lower survey biomass during the cold period of 2006–2012 (Honkalehto and McCarthy 2015). With growth of the strong 2012 year class, biomass exceeded 4 million t in 2014 and 2016, another warm period. The 2026 regional estimates included the Steller sea lion conservation area (SCA) and the Northern Extension (Table 19). The SCA is a traditionally reported subset of the survey used to evaluate pollock abundance in areas considered sensitive to Steller sea lions.

Historical abundance at age

The historical series showed strong pulses of age-1 fish in 1997, 2007, 2009, 2014 and 2024 (Table 20). The provisional 2026 estimates were largest at ages 2 and 3: 3.73 and 3.96 billion fish, respectively, compared with 2.03 billion age-1 fish.

The ATS age compositions show pulses of young fish and the progression of cohorts through successive surveys (Figure 15). The highlighted 2018 year class appears at age 4 in 2022, age 6 in 2024 and age 8 in 2026. Ages 2 and 3 dominate the provisional 2026 composition. The 2026 estimates use the BTS age–length key applied to ATS population length frequencies; FT-NIRS ages from the 2026 ATS samples are expected in 2027. Blank years represent gaps in the age-composition series.

2026 survey design and results

The 2026 ATS covered the EBS shelf from approximately 60 m depth to the shelf break between 30 May and 4 August. Core-area transects were spaced at 20 nmi; selected transects extended into the Northern Extension at 40 nmi spacing. Survey timing was similar to 2022, with a longer duration in 2026 because of special projects. The area east of 170° W was surveyed from 30 May to 25 June, and the area west of 170° W from 26 June to 4 August.

The 2026 core-area estimate was 12.7 billion fish and 3.682 million t of biomass (Table 21). Biomass increased by 28% relative to the 2024 estimate of 2.875 million t (11.4 billion fish). The 2026 biomass estimate was 4% below the 2022 estimate of 3.834 million t (9.67 billion fish) and 16% above the 1994–2024 survey mean of 3.176 million t. These are survey estimates; assessment intake and adoption remain separate decisions.

Provisional 2026 ATS age compositions over supported lengths were estimated by applying the FT-NIRS-based BTS age–length key to ATS abundance-at-length (Appendix G). Midwater pollock were concentrated between the 100 m contour and the shelf break, particularly northwest of Unimak Pass and between Zhemchug and Pervenets canyons. Length distributions suggested that presumed age-1 fish (<20 cm fork length) formed dense schools on the northwestern shelf, with smaller concentrations east of the Pribilof Islands and near Unimak Pass. Presumed age-3+ fish accounted for most biomass, with 74% of their biomass west of 170° W.

Provisional abundance at age from the 2026 BTS keys

We estimated provisional ages by matching ATS lengths to the 2026 BTS FT-NIRS age–length key, then converting those ages to traditional ages using paired readings. Ages 2 and 3 dominated the resulting distribution (Table 22; Figure 16). Fish beyond the key’s length range represented less than 0.001% of core-area abundance. The technical appendix describes the keys, calibration and allocation assumptions.

Biomass and mean weight-at-age

We applied the same age keys to biomass and divided biomass by abundance to estimate mean weights at age. The resulting mean weights are presented in Table 23 and Figure 17.

Survey uncertainty and assessment treatment

We estimated ATS biomass sampling error with the established one-dimensional geostatistical method, which accounted for spatial patterns along survey transects (Petitgas 1993; Walline 2007; Williamson and Traynor 1996). The 2026 sampling error was 3.4% of estimated biomass, compared with a historical average of 4.4%. Complete core-area coverage at 20 nmi transect spacing likely contributed to the lower error.

For assessment use, we increased the survey errors to allow for additional uncertainty, including target strength and trawl selectivity. We scaled the assessment coefficients of variation to average 20% over 1994–2026 and assigned a value of 45% to 2000 (Table 18).

Spatial and historical patterns

The ATS index used in the assessment covered the water column down to 0.5 m above the seafloor, while the historical heatmap showed biomass from near the surface to 3 m above the bottom (Figure 18). Biomass was low during 2008–2012, especially in 2008–2009, and increased in 2014–2016. The maps also showed shifts in the strength and location of concentrations along the western and southern shelf. The Northern Extension contained an additional 0.078 million t beyond the 3.682 million t core-area estimate (Table 19).

Biomass time series and observation errors

The series contained 20 survey estimates between 1994 and 2026. We plotted approximate 95% sampling intervals around each biomass estimate using the survey standard errors (Figure 19; Table 18). Gaps in the annual series marked years without a survey estimate. These intervals described survey sampling variability; the assessment used larger errors to allow for additional uncertainty.

Biomass varied strongly along the survey tracks. Concentrations were highest on parts of the western and southern shelf and generally lower in the far north (Figure 20). The map included the Northern Extension and showed GMT contours of mean biomass per sampling interval (tons per EDSU). The map uses approximately 10-nautical-mile cell means, with the smoothed surface displayed within 30 km of sampled cell centers.

4.2.3 Acoustic vessel-of-opportunity index

The acoustic vessel-of-opportunity (AVO) index provides a relative-abundance observation for age-1 and older midwater pollock within the U.S. EEZ (Honkalehto et al. 2011; Lauffenburger et al. 2025). The 2026 observations were collected at 38 kHz from 29 May to 5 August aboard the summer bottom-trawl charter vessels. The index covers the water column from 3 m above the seabed to 16 m below the surface.

Annual index

Relative AVO backscatter is lowest at 0.299 in 2009 and highest at 1.55 in 2015 (Table 25; Figure 21). It is 0.863 in 2024, 1.07 in 2025 and 1.12 in 2026, with sampling CVs of 2.72%, 5.26% and 4.55%, respectively. The 2025 and 2026 sampling confidence intervals overlap. The display series covers 2009–2026, excluding 2020, when no bottom-trawl survey took place. Each annual area-integrated estimate is divided by the mean of the 17 estimates to give a mean-one series. The table also retains total pollock backscatter, in millions of square metres, with sampling errors and scaled confidence intervals. This is an acoustic backscattering cross section, rather than geographic area (Lauffenburger et al. 2025).

For the nine paired survey years in the 2009–2026 display period, AVO total pollock backscatter and revised ATS biomass have a squared Pearson correlation of 0.89. This association is descriptive: AVO covers 3 m above the seabed to 16 m below the surface, while the revised ATS index extends from 0.5 m above the seabed to 16 m below the surface. The vertical domains differ. The 2026 AVO report gives 0.90 using an ATS 2026 estimate of 3.62 million t; the comparison here uses the revised ATS estimate of 3.682 million t (AFSC-RACE MACE 2026).

Spatial distribution and sampling coverage

Strong backscatter occurs along western EBS tracks in the recent maps, with weaker returns interspersed along central and southeastern tracks (Figure 22). The annual panels use a common map extent and color scale while showing differences in track coverage.

The longer series also contains alternating strong and weak returns along the sampled shelf (Figure 22). The year 2020 is omitted because AVO observations are unavailable. Survey coverage and processing vary among years. Inferences about population redistribution require comparable sampling and integration across years.

The number of observed survey intervals ranges from 5,557 in 2009 to 12,229 in 2024 (Table 26). Zero shares fall from 56.3% in 2009 to 7.8% in 2015, vary subsequently, and are 14.9%, 5.0% and 14.2% in 2024–2026, respectively.

The maps summarize observed pollock backscatter in approximately 20-nautical-mile cells, including zeros. GMT gridding and contours show the mean backscatter in m² nmi⁻² on a common color scale. Surfaces extend up to 45 km from sampled cell centers; more distant areas remain masked. The annual AVO index integrates backscatter over the survey area and is reported in million m². Survey coverage and processing vary among years, so comparisons of spatial patterns depend on comparable sampling.

Assessment use and observation uncertainty

The AVO assessment index is 2.01 million m² in 2024, 2.50 million m² in 2025 and 2.60 million m² in 2026 (Table 27). Its 20 observations cover 2006–2026, excluding 2020. The assessment uses the newly processed 2011 and 2013 estimates and their sampling errors (AFSC-RACE MACE 2026). The 2006–2008 estimates retain the legacy rescaling described in the 2024 assessment (Ianelli et al. 2024).

Survey sampling errors describe one-dimensional geostatistical variability. The assessment applies additional observation-error inflation to an arithmetic mean CV of 23% across its 20 observations. The two newly processed years use the existing modern-year error inflation rule, followed by common recalibration of all 20 CVs to that mean. Assessment errors differ from sampling errors and from the ATS mean assessment CV of 20%.

For the Normal index likelihood, arithmetic observation SEs equal the retained assessment index multiplied by its selected CV. For the display series, let ItI_t denote the original index, I‾\bar I its 17-year mean and Rt=It/I‾R_t=I_t/\bar I. The same constant rescales its index, SEs and confidence limits, leaving the CV unchanged:

SE(Rt)=RtCVt,[Lt,Ut]=It±1.96ItCVtI‾. \mathrm{SE}(R_t)=R_t\,\mathrm{CV}_t,\qquad [L_t,U_t]=\frac{I_t\pm1.96\,I_t\mathrm{CV}_t}{\bar I}.

The source 95% interval is represented by the half-width 1.96ItCVt1.96 I_t\mathrm{CV}_t, checked for every observed year. The displayed intervals describe survey sampling uncertainty with normalization treated as a change of units; assessment error inflation is a separate model input.

4.3 Other data

Model 26.0 fitted the 12 historical CPUE observations from 1965–1976 using fishery selectivity and fishery weights at age. We retained the observations and errors from the reference fit through 2024.

Fixed biological assumptions

We retained the 2024 biological assumptions (Ianelli et al. 2024). Natural mortality was 0.9 yr⁻¹ at age 1, 0.45 yr⁻¹ at age 2 and 0.3 yr⁻¹ at ages 3–15+. Maturity at ages 1–15+ was 0, .008, .289, .641, .842, .901, .947, .963, .970, 1, 1, 1, 1, 1, 1. The model calculated April spawning biomass one quarter-year after the start of the year and applied a female fraction of 0.5 once to sex-combined abundance. We used a 15-by-15 identity matrix for ageing error, matching the archived ADMB configuration. This likelihood assumption treated ages as exact after data preparation, which used FT-NIRS age conversion and age–length keys.

All weight schedules covered ages 1–15+ for the combined sexes in kg per fish. The model used fishery weights to calculate catch biomass, BTS weights to calculate population biomass and A-season weights to calculate spawning biomass.

Population and spawning weights

Population weights use BTS observations through 2026. Three historical values retain their previous treatment; details are in the technical supplement. For spawning biomass, we replaced the older weights at ages 3–15+ with A-season fitted values for 2024–2025 and projections for 2026. Within the common-year comparison, this update changed the 13 values at ages 3–15+ in 2024. We retained baseline weights at ages 1–2; age-2 maturity was .008.

ATS and AVO weights

We retained each historical schedule through 2024 and carried its weights forward to 2025. After BTS-ALK and conditional TMA preparation, we calculated provisional 2026 ATS weights by dividing biomass by the corresponding abundance. For age 15+, we pooled biomass and abundance before division. Appendix G documented the supported lengths and unallocated tail. We used the 2026 ATS vector as a proxy for AVO weights, although the historical schedules differed.

Section 4.1.3 described the rationale for changing weight estimation. Weight-schedule uncertainty remained separate from the assessment’s conditional parameter uncertainty. Native forecasts repeated the 2026 weight vectors.

4.3.1 Age-composition input sample sizes

The full-data Model 23.0 fit uses fishery composition N=443, 578 and 530 for 2023, 2024 and 2025, respectively (Table 24). These are the rounded continuity-scaled harmonic estimates from the corrected sampler bootstrap, applied in the completed full-data Model 23.0 fit at the author’s direction. The bootstrap preserves linked sampling units within fishery strata and uses 10,000 replicates per year. ATS 2026 uses N=94, and BTS retains the selected 2026 N, shown as 131. Fishery N is fixed at 10 in each year from 1964–1977. The three composition-likelihood multipliers are 1.

Model 26.0 fits age compositions with a multinomial model. The baseline retains likelihood sample sizes from the bridge workbook. These likelihood sample sizes differ from counts of fish sampled and from diagnostic effective sample sizes. For every fishery or survey year, the final assessment must provide the raw sampling information, starting sample size, adjustment method, and final sample size used in the likelihood. The 2020 biomass estimate remains a separate fitted survey observation.

One-step-ahead (OSA) residuals compare an observation with its conditional prediction after preceding age categories have been considered. The OSA and Francis comparisons document the selected weights and observed-data residual patterns in Section 6.1.6.

5 Analytic approach

5.1 Main and comparison models

Model 26.0 (Rceattle) is the adopted model for Tier 3 calculations and specifications. Models 23.0 and 23.2 provide comparisons with the previous assessment and the transition in model structure. Other sensitivities separate the early Foreign fishery (1964–1990) from the later domestic fishery (1991–2026) and vary the penalty on declining selectivity. Model 26.1.2 is the Early-late fishery split sensitivity. The fits and retrospective comparisons hold the process standard deviations fixed at the values estimated by its marginal model. Model 26.0 uncertainty and retrospective diagnostics are described below.

5.1.1 Model 23.0 and impact of new data

As in past years, we incrementally introduced new data relative to the previous assessment while retaining the Model 23.0 formulation. We began with total catch through 2026, incorporating the revised catch estimates for 1991–2026 (2026: 1,312,504.58 t) and extending the model endpoint and parameter and projection horizons to accommodate the added years. At this first step, fishery age compositions and survey observations retained their historical coverage. We then updated weight-at-age and A-season spawning weights, followed by fishery catch-at-age data and their information weights.

The survey updates followed in sequence: the bottom-trawl survey (BTS), the acoustic-trawl survey (ATS), and the acoustic vessels of opportunity (AVO) index. BTS retained the 2020 survey gap and annual information weights, including the real-valued 2026 input. ATS incorporated the selected age-1 rule and provisional 2026 age information, and AVO incorporated its annual observations and assessment-error recalibration. Historical revisions and uncertainty recalibration were included with each survey’s update (Section 4.2.2; Section 4.2.3).

Each step includes all preceding updates, so its estimated effect depends on the order in which the data were added. The resulting 2026 estimates are summarized in Table 29, and the cumulative annual point estimates are shown in Figure 24. These comparisons use matched definitions of population-weight biomass, female spawning biomass, age-1 recruitment and maximum realized fishing mortality across ages. Model equations are given in the model-equations appendix.

The saved 2027 spawning-biomass and young-abundance projections from the cumulative input-update analyses are compared in Figure 25. These diagnostic projections retain the earlier 2026 catch estimate of 1,310,000 t; the 2026 estimates above use the revised catch inputs. The display starts with Catch + 2026 endpoint, followed by + Fishery age data and the subsequent survey updates. The intervening weight-at-age and A-season spawning-weight updates remain incorporated in the fishery-age and later fits. Abundance at ages 1–3 is measured at the start of 2027, before removals; spawning biomass includes mortality to spawning time. Projection settings are detailed in the technical supplement. Management projections retain their separate catch, selectivity, weight and recruitment assumptions (Section 7).

The input sequence and configuration comparison answer different questions. The former retains the Model 23.0 formulation while adding observations and updating schedules. The latter compares formulations on matched observations and biology (Table 30).

Approximate distributions compare the change in spawning biomass from 2026 to 2027 (Figure 26) and the historical change in total abundance at ages 1–4 from 2025 to 2026 (Figure 27). They show the same selected cumulative sequence, followed by Models 23.2 and 26.0. Their input and projection settings are documented in the technical supplement. Each distribution retains its matching fitted-parameter covariance between years and, for abundance, among ages. The normal approximations are conditional on the model and biological and projection assumptions.

Among the additions in the saved 2027 projection comparison, ATS produced the largest increase in female spawning biomass: from 2.685 to 2.975 million t, an increase of about 290,000 t (10.8%) relative to the preceding BTS step. AVO increased projected spawning biomass a further 61,000 t (2.0%), to 3.036 million t. The effects on estimated 2026 spawning biomass differed: fishery age data produced the largest increase, about 213,000 t (8.4%); ATS reduced it by about 73,000 t (2.6%), and AVO increased it by about 47,000 t (1.7%). These are successive changes within the specified sequence, with each survey contrast including its historical revisions and error calibration.

5.1.2 Model 23.2 fitted to the 2026 assessment data

Model 23.2 is a structural bridge between the ADMB continuity model and the Rceattle configuration. Its annual spawning-biomass and recruitment trajectories retain their documented scope. The established zero-variance management quantities are excluded from management comparisons. Current configuration effects use verified saved population outputs and their stated units. The comparison of Models 23.0 and 23.2 includes matching local asymptotic uncertainty ranges (Figure 28).

5.1.3 Model 26.0 fitted to the 2026 assessment data

Model 26.0 uses one fishery and fixed weight-at-age schedules. The updated base model fit retains its native working-likelihood, parameter bounds, selectivity forms, priors and fixed biological assumptions. We check outputs against the written inputs and saved native quantities. Population-weight biomass, female spawning biomass, age-1 recruitment and maximum fishing mortality retain distinct definitions. Their annual estimates and matching local asymptotic uncertainty are compared with Model 23.2 in Figure 29.

5.1.4 Model 26.1: Foreign and Modern domestic fisheries

The split-fishery alternatives distinguish Foreign fishing in 1964–1990 from Modern domestic fishing in 1991–2026. Model 26.1.0 supplies the fitted split-fishery comparison; Model 26.1.1 reduces the declining-selectivity penalty, and the zero-penalty case removes it. Model 26.1.2 extends that formulation by estimating the Modern annual selectivity-process SD while integrating over annual selectivity effects. The Foreign process SD remains fixed. Local uncertainty uses the verified marginal information for this alternative; its observation diagnostics condition on the fitted annual effects.

6 Results

6.1 Model 26.0 assessment

Model 26.0 provides the main estimates of stock size and the basis for the Tier 3 catch limits presented here. Results from the other model configurations, including Model 26.1.2, show how alternative assumptions affect the assessment. Additional analyses describe uncertainty in Model 26.0 estimates and how those estimates change when recent years of data are removed. Comparisons with past assessments use the data and catch advice reported in each assessment year.

6.1.1 Population estimates and uncertainty

The Model 26.0 base model estimates 2026 total biomass at 12.162 million t, female spawning biomass at 3.057 million t, age-1 recruitment at 36.3 billion fish, and maximum fishing mortality across ages at 0.299 per year (Table 31).

The local asymptotic 95% ranges in the tables use the revised fit’s native covariance. The uncertainty figure is shown in Figure 30. Annual estimates and ranges appear in Table 32.

Regularized-posterior intervals use all 5,000 existing draws, using the final reported summaries (Table 33). The 2026 female spawning-biomass median is 2.946 million t, with a central 95% credible interval of 2.450–3.584 million t. Total-biomass median is 11.462 million t, with interval 9.215–14.719 million t. Age-1 recruitment median is 31.1518 billion fish, with interval 12.2880–91.0616 billion fish. These are the final reported MCMC summaries; production point estimates and asymptotic intervals retain their separate roles.

Numbers-at-age track cohorts through the population (Figure 31). This shows periods of how recruitment and changes in fishing mortality by age affect abundance relative to their mean abundance estimates (and uncertainty) propagates through time. Actual point estimates are reported in Table 34, while the 2026 abundance-at-age estimates (and asymptotic uncertainties) are shown in Table 35.

Comparison with the 2024 assessment

The 2018 year class remains a large recruitment point estimate (Figure 32). Its age-1 abundance in 2019 is 87.8 billion fish in the Model 26.0 base model, compared with 81.1 billion in the accepted 2024 assessment, a revision of 8.3%. The revision reflects both updated observations and changes in model structure.

The estimate for the same 2024 female spawning biomass changes from 3.389 million t in the saved 2024 assessment to 3.526 million t in Model 26.0, a revision of 4.0%. Within the trajectory, spawning biomass changes from that 2024 estimate to 3.057 million t in 2026 (-13.3%). Total biomass changes from 10.767 million t to 12.162 million t over the same years (13.0%). These within-trajectory changes differ from shared-year assessment revisions.

The recruitment comparison uses calendar age-1 year and billion-fish units (Figure 32). Model 26.1.2 results are included to examine how recruitment estimates for the early period change relative to the 2024 assessment. Historical values are point estimates. Current error bars use each model’s local asymptotic covariance: the base-model covariance for Model 26.0 and the marginal information for Model 26.1.2. Recent years without a historical estimate are identified. These intervals describe uncertainty around the fitted estimates.

The two assessments project different spawning-biomass paths through 2028 (Figure 33). The comparison retains each assessment’s Scenario 2 catch assumptions; the current uncertainty band propagates local assessment-parameter uncertainty.

Recruitment per unit of spawning biomass

The log recruits-per-spawner diagnostic from the 2024 assessment is updated using the Model 26.0 estimates (Figure 34). For each year of hatching, age-1 recruitment in the following year is divided by female spawning biomass in the year of hatching. Taking the natural logarithm puts proportional changes on a comparable scale: higher values indicate more recruits per unit of spawning biomass. The series shows substantial variation among year classes. The 1978, 2008 and 2018 year classes have particularly high recruits-per-spawner values. Following the strong 2018 year class, the ratio declined through the 2022 year class; estimates for 2023–2025 are higher but remain less certain. The spawning-biomass panel generally shows lower ratios at higher biomass, with considerable variation among years at similar biomass. This pattern can reflect density dependence, environmental conditions and estimation uncertainty. Spawning biomass appears in both the horizontal axis and the ratio, which can contribute to the apparent relationship. Model 26.0 uses mean recruitment rather than an estimated Ricker curve. The figure provides a descriptive check on productivity using point estimates of the recruitment-to-biomass ratio.

Biological schedules and selectivity retain their age, sex and year definitions (Figure 35; Table 36; Table 37). Fishing mortality is also shown by age (Figure 36). Whole-year spawning exploitation compares paired spawning-biomass calculations from the base model production fit (Figure 37). For the interval from spawning in 2026 to spawning in 2027, its production-point estimate is 13.7%: 3.326 million t with fishing versus 3.853 million t without fishing. The branches share prior fishing history and their spawning-date starting population, with 1.375 million t annual catch assumed in 2027. The separate MCMC posterior median for this exploitation fraction is 14.5%, with a central 95% credible interval of 11.2–18.4%. These paired-state calculations carry the revised fishery-weight schedule into 2027 and retain the fixed 1.375 million t catch assumption. The production-fit point remains separate from that posterior interval.

6.1.2 Estimated model parameters

The parameter-family summary identifies fitted parameter groups and their asymptotic uncertainty (Table 38). Complete estimates and the largest parameter correlations are retained in the detailed estimates appendix. The summary likelihood contributions are in Table 39.

6.1.3 Fits to the observations

The fitted indices follow the main rises and falls in the survey series, including the low ATS biomass in 2006–2009 and its subsequent increase (Figure 38). Annual departures remain. The BTS residuals include negative departures in 2006 and 2009 and positive departures in 2014–2015, each outside the plotted 95% reference range. The AVO observation in 2015 is also higher than fitted, whereas all ATS biomass residuals fall within that range (Figure 39; Table 40). Thus, the broad survey trends are represented more closely than some individual annual observations. BTS residuals account for covariance among survey years.

The fishery selectivity curves show substantial changes in the ages most vulnerable to fishing, with dome-shaped patterns in many years and flatter patterns in others (Figure 40). BTS selectivity generally increases with age and approaches a plateau, while the ATS curve, shared with AVO, is relatively flat at older ages (Figure 41; Figure 42). Recruitment varies strongly among years: the 2018 year class, entering at age 1 in 2019, has the largest positive departure from the fitted recruitment level.

The mean-age comparisons show that the model follows most of the observed changes in survey age composition and closely tracks fishery mean age in the domestic period. The clearest sustained fishery discrepancy occurs in the early years, when predicted mean ages are higher than observed (Figure 43). The observed bars show plus or minus two standard errors of mean age; they describe sampling uncertainty, rather than uncertainty in the fitted population. Fishery age observations end in 2025. The annual composition panels show how these mean ages arise from the proportions at each age and allow individual cohorts to be followed as they age (Figure 44; Figure 45; Figure 46; Figure 47).

Aggregate observed and fitted age proportions agree closely, especially for the fishery, but the residual panels retain patterns by age and year (Figure 48; Stewart and Monnahan (2025); Monnahan et al. (2026)). For example, BTS residuals include extended runs of the same sign at several ages, and the early fishery residuals also show structured departures. Averaging across years can obscure these differences. The OSA residual standard deviations are below one for all three sources (about 0.76 for the fishery, 0.86 for BTS and 0.64 for ATS), and the QQ plots are generally narrower than the standard-normal reference, although some BTS tail residuals are large. Close aggregate fits therefore need to be considered alongside the annual patterns. The afscOSA v0.0.1 displays retain the native Model 26.0 OSAs and selected likelihood sample sizes. They describe conditional observation fit under the working-score approximation; parameter uncertainty is outside their scope.

6.1.4 Profile likelihood diagnostics

A profile examines how strongly the observations and model assumptions constrain ATS survey catchability in Model 26.0. Catchability scales the survey index relative to the population available to the survey. We fixed this parameter at 17 values from 0.45 to 0.65, including the freely estimated value of 0.51694, and re-estimated all other active parameters. The grid uses eight equal intervals on each side of the estimated value: approximately 0.00837 below it and 0.01663 above it. Data, bounds, likelihood terms, and penalties match the Model 26.0 fit, including the updated 2011 and 2013 AVO observations (Figure 49).

The best fit remains at catchability 0.51694. Lower or higher values increase the negative log likelihood (NLL), indicating a poorer overall fit after the other parameters have adjusted. The conventional change of 1.92 NLL units is crossed between 0.45000 and 0.45837 on the lower side and between 0.58347 and 0.60010 on the upper side. Linear interpolation between these points gives approximate crossings of 0.4576 and 0.5838. These are diagnostic bounds from the sampled profile; the objective includes model penalties, and the crossings have been interpolated rather than directly fitted.

The component breakdown shows how the model balances the different data sources. At catchability 0.45, the total NLL increases by 2.48 units. Index likelihoods contribute 2.36 units, while the combined composition fit improves by 0.43 units. The ATS index and compositions fit less well, while BTS compositions fit better. At catchability 0.65, the total increase is 6.80 units. Compositions contribute 4.50 units, largely from the BTS, and selectivity penalties contribute 1.93 units. The combined index term changes by only 0.14 units because improved BTS index fit partly offsets poorer ATS index fit. Thus, the preferred catchability reflects agreement across surveys, fishery observations, and selectivity assumptions.

All 17 fits have maximum absolute gradients below 10−410^{-4} and positive-definite Hessians. Seven points required additional numerical refinement or successful optimizer confirmation. Weighted NLL components sum to the total objective at every point. Scientific evaluation should also consider sensitivity to composition weighting and selectivity assumptions.

The final ATS-q posterior median is 0.5093, with central 95% credible interval 0.4514–0.5755. The profile minimum is 0.51694, with approximate profile limits 0.4576–0.5838. Figure 50 compares the negative log ATS-q marginal density with the optimized profile NLL. The kernel density integrates to one, and each displayed curve is centered at its own minimum over ATS q. The marginal integrates over the other parameters and includes posterior regularization; the profile optimizes those parameters under the native penalized objective. Panel B fits weighted quadratic curves directly to individual-draw native NLL components and compares them with the profile components. All 5,000 draws contribute; binning is excluded. MCMC curves are centered at the ATS-q marginal mode and displayed over the central 99% of sampled q. These conditional mean curves have a different interpretation from the negative log marginal density, which has no unique additive decomposition into the native likelihood terms. The smoothers summarize the broad component trends; tail coverage is limited by the available draws.

The paired MCMC draws show the relationships among ATS q, summed abundance at ages 2–5 in 2026, age-1 abundance in 2019 (the 2018 year class), and projected 2027 female spawning biomass (Figure 51). Diagonal panels show their marginal densities. All four quantities are paired within each saved draw.

Projected 2027 female spawning biomass is most strongly associated with the summed abundance of ages 2–5 in 2026 among the quantities shown (r=0.84r = 0.84). This contrasts sharply with the 2024 assessment, in which projected 2025 spawning biomass depended heavily on the estimated magnitude of the 2018 year class (Figure 53 of the 2024 SAFE). The 2018 year-class dependence remains in the projection, as shown by its positive correlation with 2027 spawning biomass (r=0.36r = 0.36), but is less pronounced than the dependence on the younger fish now approaching or contributing to spawning biomass.

At each fixed ATS catchability, we also project 2027 female spawning biomass and its conditional 95% confidence interval (Table 41). The projection uses 1,375 kt catch in 2027, mean 2023–2025 fishery selectivity, April 1 spawning, the weight schedules, and the age-15+ group. These conditional profile calculations retain the biological schedules of the fitted assessment.

These intervals propagate fitted-parameter uncertainty using the inverse fixed-q penalized Hessian and the delta method on log spawning biomass. They condition on each ATS q and the stated projection assumptions. They exclude uncertainty in ATS q, future recruitment process variation, and weight-at-age schedules. Thus, they describe uncertainty in the estimated 2027 SSB at each profile point.

6.1.5 Retrospective patterns

Across the full nine peels ending in 2017–2025, Model 26.0 female spawning-biomass Mohn’s rho is +0.121 (Table 42). Age-1 recruitment rho is −0.0985, and maximum fishing-mortality rho is −0.0636. Each statistic averages the relative revision between a peel’s terminal estimate and the full-2026 estimate for that same calendar year. The annual revisions are reported in Table 43.

The paired retrospective comparison shows female spawning biomass, age-1 recruitment and maximum fishing mortality for Model 26.0 and the Early-late fishery split Model 26.1.2 sensitivity (Figure 52). Each colored curve removes one through nine terminal years and is compared with its own analysis’s full 2026 reference. Model 26.0’s full nine-peel statistics are reported above.

The conditional Model 26.1.2 comparison has nine-peel spawning-biomass rho of +0.0735, recruitment rho of −0.133, and maximum fishing-mortality rho of +0.00226. Both configurations show positive average spawning-biomass revisions and negative average recruitment revisions, while their average fishing-mortality revisions differ. These full-window summaries describe the overall direction of retrospective change across all nine endpoints.

The Model 26.0 simulated-data and posterior-predictive retrospective experiments provide separate conditional comparisons (Section 6.3.1).

Historical retrospectives

Successive assessments provide different estimates of biomass as observations accumulate and methods change. Following Figure 63 of the 2024 SAFE, Figure 53 compares beginning-of-year age-3+ biomass from earlier assessments with the Model 26.0 series. The 2024 comparison uses the published values in the official SAFE Table 27. There was no assessment fit in 2025.

For this historical comparison, age-3+ biomass is the sum of beginning-of-year numbers at ages 3–15+ multiplied by the corresponding fishery weights at age in each year. This definition differs from total population-weight biomass reported elsewhere in the assessment.

The 2026 assessment estimates age-3+ biomass in 2023 at 11.983 million t, compared with 9.695 million t in the 2024 assessment, an increase of about 24%. The corresponding estimates for 2024 are 10.185 and 9.415 million t, a difference of about 8.2%. The Model 26.0 trajectory declines from 14.438 million t in 2022 to 8.774 million t in 2025, then rises to 13.286 million t in 2026. Earlier assessment trajectories show that both the magnitude and timing of biomass changes have been revised over time.

These historical comparisons combine the effects of new observations, revised biological inputs and changes in model structure. The retrospective peels above instead remove recent years within a specified model framework. The historical figure is therefore a record of assessment revisions, with each series retaining its original assumptions and available years.

6.1.6 Age-composition weighting comparison

The age-composition diagnostics suggest relatively minor changes to the weights used in the 2026 assessment (Figure 54; Figure 55). Given the small suggested adjustments, the 2023–2025 fishery age compositions therefore retain input information weights of 443, 578 and 530. These weights determine the influence of the compositions in model fitting. The data section reports the raw numbers of fish sampled.

Composition weighting can be evaluated more fully in future assessments, including alternatives such as the Dirichlet-multinomial distribution, which allows greater variation among age samples than the multinomial model. Such comparisons would help assess whether estimating this additional variation within the model improves the treatment of age-composition data and changes the resulting stock estimates.

6.2 Model 26.1 split-fishery alternatives

Models 26.1.0 and 26.1.1 separate the Foreign fishery through 1990 from the Modern domestic fishery beginning in 1991. Their annual selectivity standard deviations are fixed at 0.5, while the declining-age penalty is 12.5 in Model 26.1.0 and 3.125 in Model 26.1.1. The zero-penalty case provides a further comparison. The Model 26.1.2 sensitivity shown here retains the 3.125 penalty and fixes the Foreign and Modern annual process standard deviations at 0.1235 and 0.582, respectively. The remaining parameters and annual selectivity effects are estimated conditionally on these values.

The likelihood comparison separates data-likelihood contributions, penalty terms and the marginal fitting criterion (Table 44). The projections use the revised ordinary fits and the Early-late fishery split Model 26.1.2 comparison. The alternatives retain matched observations, likelihood weights and projection assumptions (Table 45).

6.2.1 Selectivity

Separating the Foreign (1964–1990) and Modern domestic (1991–2026) fisheries changes the fitted selectivity most visibly near the boundary between the two periods. Over much of the later period, Models 26.0 and 26.1.0 retain similar annual age patterns, including the peaks and declines at older ages (Figure 56). The split allows the Foreign curve to differ more freely from the Modern curve, while Model 26.0 represents the history as a single fishery.

Both models estimate a shift from 1990 to 1991 toward lower relative selectivity at younger ages and higher relative selectivity at ages 11 and older. The shift is larger in Model 26.1.0: at age 5, the change is about −0.69 on the native mean-one scale, compared with −0.31 in Model 26.0; at ages 12 and older, the increases are about 0.55 and 0.24, respectively (Figure 57). This comparison shows how the split changes the estimated transition. The fitted curves alone establish neither an abrupt change in fishing practices nor an improvement in the population estimates; the observation fits and retrospective results provide the complementary checks below.

The full-history curves are divided by each year’s maximum so that their shapes can be compared. The boundary-year display instead retains native mean-one normalization, and its differences refer to that scale. These are fitted point curves. The Model 26.1.2 curves used in subsequent comparisons retain the fitted selectivity states from its fixed-SD conditional fit and remain distinct from the Model 26.1.0 comparison here.

6.2.2 Fishery age-composition fits

We compared Models 26.0 and 26.1.2 using the same 62 annual fishery age compositions and likelihood weights (Figure 58; Figure 59). Model 26.0 fitted one fishery across the full record; Model 26.1.2 separated the Foreign fishery through 1990 from the Modern domestic fishery beginning in 1991. We displayed both models over those same periods to compare their fits directly. Both models reproduced the dominant age groups in the combined compositions, while the annual plots revealed differences that the combined summaries obscured.

Model 26.1.2 fitted the Modern domestic observations more closely. It reduced the sample-weighted root-mean-square difference in age proportions from 0.693 to 0.590 percentage points and the root-mean-square error in annual mean age from 0.123 to 0.0963 years. Both models predicted a younger mean age than the observations showed in 1991, but Model 26.1.2 reduced that discrepancy from 0.510 to 0.339 years. The smaller differences across ages and years showed that the split-fishery configuration improved the modern fit rather than simply matching its combined age distribution.

Model 26.0 fitted the Foreign-period observations more closely. Model 26.1.2 increased the sample-weighted age-proportion error from 2.67 to 3.43 percentage points and the annual mean-age error from 0.655 to 0.696 years. Both models predicted older mean ages than the early observations showed, particularly in 1964–1965 and 1970. The age-by-year panels showed persistent overprediction at several older ages and underprediction at younger ages during much of the early record. Separating the fisheries therefore improved the modern fit while leaving larger discrepancies in the Foreign period.

6.3 Further model evaluations

6.3.1 Observation-error retrospective self-test

In response to Plan Team and SSC requests to investigate retrospective patterns, we developed a new simulation-based retrospective experiment for this assessment (Figure 60). Its distinctive feature is a paired design that examines revisions both at the fitted parameter estimates and across plausible parameter states from the regularized posterior. One set of ten simulated datasets uses the fitted parameters; a second set uses ten posterior parameter draws. Each dataset has its own full 2026 fit and nine optimization peels ending in 2017–2025. Revisions compare each peel’s terminal estimate with its own full fit for the same calendar year. This approach extends the usual retrospective analysis by examining how observation variation and uncertainty in the generating parameters influence the revisions, providing additional context for interpreting the assessment’s retrospective pattern.

Across all nine peels ending in 2017–2025, Model 26.0 assessment Mohn’s rho for female spawning biomass is +0.121, compared with median values of −0.0117 for datasets generated at the fitted parameters and −0.0574 for datasets generated from posterior draws. The assessment value exceeds every simulated rho in both sets: the fixed-parameter range is −0.115 to +0.0335, and the posterior-draw range is −0.0971 to +0.116. Thus, the positive average spawning-biomass revision in the assessment is stronger than that reproduced by these simulated datasets.

For age-1 recruitment, the assessment’s nine-peel rho is −0.0985, within both simulated ranges. Median recruitment rho is −0.00751 in the fixed-parameter set and +0.0830 in the posterior-draw set. The contrast between spawning biomass and recruitment shows that the retrospective pattern depends on the population quantity considered.

The paired design explores how observation variation and uncertainty in generating parameters contribute to the full nine-peel pattern. Ten datasets per branch provide an exploratory comparison. The technical supplement describes the fixed process history, data-generation approximations and other conditioning assumptions. These experiments assess biomass and recruitment revisions. Confidence bands describing retrospective ABC or OFL patterns are beyond the scope of this work but would be interesting to evaluate.

6.3.2 Posterior diagnostics and predictive checks

The regularized posterior explores parameter uncertainty separately from the production base-model estimates (Figure 61; Figure 62; Figure 63). Four chains each retained 1,250 draws after 1,000 warmup iterations. Combined parameter diagnostics give maximum R-hat 1.024 and minimum bulk ESS 242, with zero divergences and zero maximum-treedepth events. The reported population quantities mix more consistently: maximum R-hat is 1.0013 and minimum bulk ESS is 3,914. MCMC standard errors of the 2026 spawning-biomass and biomass means are about 4,110 t and 20,600 t; their first-half versus second-half mean shifts are less than 0.03 posterior standard deviations. These diagnostics describe the saved chains and retain the parameter-level qualifications.

Final posterior summaries

The posterior mean female spawning biomass in 2026 is 2.965 million t, with a central 95% credible interval of 2.450–3.584 million t (Table 46). These summaries use all 5,000 retained MCMC draws under the regularizing priors and fixed biological inputs. Full-precision results are downloadable as CSV files containing terminal stock and selectivity summaries (CSV), annual population intervals (CSV), summaries of all 1,266 parameters (CSV), and spawning-exploitation intervals (CSV).

Predictive checks ask whether the fitted model can generate data that resemble the observations (Figure 64; Figure 65). We selected 1,000 MCMC draws spanning the four chains. Each draw supplies a possible set of model parameters, from which a new set of observations is simulated. The shaded ranges therefore include both parameter uncertainty and the sampling variation assumed by the model. Points outside these ranges, or repeated patterns of differences, help identify features the model struggles to reproduce. The ranges apply to each age or year individually; some points outside them are expected even when the assumptions are appropriate.

For the indices, simulated observations use the same error assumptions used in fitting, including the relationships among BTS errors. The overall BTS mismatch measure is as large as the observed measure in only 0.2% of the simulations, indicating that this feature of the BTS data is rarely reproduced. Normal error assumptions also allow some simulated indices to be negative.

For age compositions, simulated fish are randomly assigned to age groups using each draw’s predicted proportions and the sample size used in fitting, rounded to a whole number. The simulations approximate the fitting method, which adds a small constant (0.001) to age proportions. The figure compares the latest three actual samples for each source with these simulated age proportions. Age conversions, weights and other biological inputs are held fixed. These checks assess how well the model reproduces observations; the retrospective analyses address how estimates change as additional years of data become available.

7 Projections and harvest recommendations

7.1 Proposed Tier 3 configuration and reference points

The proposed fishery selectivity is the mean of the 2023–2025 annual curves, the latest three years with fishery age observations. Each age is averaged before scaling the resulting curve to a maximum of one. The separately inferred 2026 curve is distinguished from directly age-informed years (the projection-input appendix).

The deterministic recruitment level uses the arithmetic mean of age-1 entries in 1978–2023, corresponding to birth cohorts 1977–2022. The less precise 2024–2026 entries are excluded. Every entry in the advice tables equals this selected historical mean. The separate projection figures add future recruitment variation to illustrate a range of possible paths. Reference points and fishing rates are reported in Table 47. The Model 26.1.2 column uses the revised Early-late fishery split comparison under the same projection assumptions.

The Tier 3 reference points are spawning-potential quantities. The ABC rule reduces fishing mortality below B40% and sets it to zero below B20%. Projections start from each fitted population and use the stated catch scenarios and biological inputs. The author-rate fraction is one, subject to the risk evaluation and final review.

The previous-year OFL-equivalent fishing mortality is reported in Section 10.

7.2 Standard harvest scenarios

The proposed projections retain the standard harvest scenarios and their common biology (Table 48). The expected-catch scenario assumes 1.375 million t in each of 2027 and 2028; the 2028 catch is a planning assumption. Short-term outputs are reported in Table 49.

The catch and female spawning-biomass panels compare Alternative 2 with recent-mean-F Alternative 3 (Figure 66; Figure 67). Black lines show the means of 1,000 future-recruitment simulations, ribbons show their 5th–95th percentiles, and ten colored trajectories illustrate individual outcomes. Each color follows the same recruitment realization across both alternatives and figures. Recruitment follows the established inverse-Gaussian method, using the arithmetic and harmonic means of the fitted 1978–2023 age-1 entries. Initial age-1 abundance in 2027 equals the historical arithmetic mean; each subsequent entry varies among simulations. The widening bands show how future recruitment variation accumulates as new cohorts enter the fishery and spawning population. Alternative 2 catch paths coincide in 2027 and 2028 because those catches are prescribed.

The projection tables retain all seven scenarios with recruitment fixed at the historical arithmetic mean (Table 50; Table 51; Table 52). The historical phase plot places the fitted 1981–2026 trajectory and deterministic Alternative 2 projections for 2027–2028 on common axes (Figure 68). The horizontal axis is female spawning biomass divided by B35%; the vertical axis is maximum fishing mortality at age divided by F35%. Both denominators are the current primary projection reference points (B35% = 2.155 million t; F35% = 0.658 per year), held constant across the trajectory. This common benchmark shows changes in the fitted stock and fishing mortality through time. The 2024 assessment used annually varying reference points; the historical positions here therefore also reflect the choice of a common current benchmark. F35% is a spawning-per-recruit proxy for FMSY, and B35% is the corresponding spawning-biomass reference point. Solid lines mark ratios of one, and the dashed vertical line marks half B35%. Two-digit year labels trace the trajectory, with the two projection years boxed and shaded yellow. The fitted 2026 position and both projected positions are above B35% and below F35%.

7.2.1 Decision table

As in past assessments, we present estimated consequences and probabilities for a range of future catches and the subsequent fishing effort implied by each choice (Table 53; Table 54). The decision table compares eight possible 2027 catches, from 10 to 2,540 kt, using Model 26.0 with the updated AVO data. The indicator definitions identify the quantities, comparison benchmarks and years used in the calculations. Together, the tables show how catch choices affect fishing mortality, future spawning biomass and age structure, and how likely each choice is to meet the specified benchmarks.

Each catch column represents a different fishing strategy. Fishing mortality is calculated to achieve that catch in 2027, then held constant through 2031. Catches in subsequent years therefore change with the projected abundance and age composition of the stock. The effort indicator gives the probability that mean age-specific fishing mortality in 2027 exceeds its 2026 value. Interpreting it as relative effort assumes that catchability and the age pattern of fishery selectivity remain fixed. It provides a comparison among strategies rather than a forecast of vessel numbers, fishing days or operating costs.

Readers can compare columns to examine the trade-off between the initial catch and subsequent stock conditions. The probability rows summarize the chance of crossing the stated biomass, fishing-mortality or age-structure benchmarks. These are conditional comparisons that support catch decisions alongside the standard harvest projections and risk table.

Entries are approximate chances out of 100. They propagate uncertainty in the fitted population, selectivity, estimated mean recruitment and comparison benchmarks. Future recruitment is held at the estimated 1978–2023 mean, and biological schedules are fixed. These probabilities describe uncertainty in the assessment estimates under each catch choice. Additional year-to-year recruitment variation and uncertainty in weights and maturity are outside these calculations. Values displayed as 0 or 100 reflect rounding.

The 1,270-kt column is retained for comparison with the earlier decision-table analysis. The expected-catch scenario elsewhere in this section assumes 1,375 kt in 2027 and 2028. The decision tables provide a broader comparison of catch choices; they use local asymptotic uncertainty rather than MCMC draws.

7.2.2 Reference point sensitivity to fishery selectivity specification

Fishery selectivity determines how fishing mortality is distributed across ages and therefore affects both the reference fishing rates and the catches obtained at those rates. The central projection uses the age-specific arithmetic mean of the raw 2023–2025 fishery selectivity curves, rescaled so that its maximum is one. This recent three-year average smooths annual variation while retaining the age pattern from the latest years with fishery age observations. Averaging precedes rescaling because normalizing each annual curve first would give a different average. Figure 69 introduces this recent-average specification and contrasts it with individual annual estimates. The inferred 2026 curve is shown separately because fishery age observations end in 2025. It provides a terminal-year comparison, while the management projections retain the 2023–2025 average.

The recent curves show that changes in fishery recruitment involve particular ages rather than a uniform shift toward younger fish. The first ascending half-maximum crossing was near age 6 in 2021–2022, compared with approximately 4.5, 5.0 and 5.2 in 2023–2025. Relative selectivity at age 5 was especially high in 2023 and then declined in 2024–2025. Selectivity at ages 1–3 remained low and varied independently. These differences matter because a curve that exposes age-5 fish more strongly can produce a different catch and spawning impact from one that concentrates fishing at older ages, even when both have the same maximum selectivity.

The full annual comparisons show which parts of each curve differ from the projection assumption (Figure 70). The repeated 2023–2025 reference makes shifts in the ascending limb, peak and older-age tail visible across 2007–2026. For example, the 2019 curve peaks near age 7 and declines substantially at older ages, whereas several earlier curves retain high selectivity across the older ages. Thus, the annual panels provide the age-specific explanation for the management differences in the next figure. The older curves represent alternative fishing patterns for sensitivity analysis. Their relevance as forecasts depends on evidence about current and future fishery conditions.

Annual selectivity alternatives give both higher and lower catch ceilings than the recent-average baseline (Figure 71). Of the twenty curves, 14 produce a higher maximum ABC in 2027 and 12 do so in 2028. Changes range from -8.2% to +12.0% in 2027 and from -5.9% to +8.4% in 2028. These are conditional sensitivities under common population, recruitment, biological and catch assumptions.

The lowest annual-curve maximum ABC occurs with the 2018 curve in 2027 and the 2019 curve in 2028. The 2025 curve changes the ceilings by +1.5% and -4.4%, respectively. The age pattern affects immediate catches and the ages surviving into the following year. F40% and F35% are recalculated for each curve; the assumed catch remains 1.375 million t in each year.

The younger-age summaries explain why a single description such as “younger selection” is insufficient (Figure 72). They separate exposure of ages 1–3, selectivity at ages 4 and 5, the first ascending half-maximum age, and changes across the full curve. For example, from 2022 to 2023 the half-maximum age falls from about 6.0 to 4.5 years, while the curve-weighted mean age changes only from 10.09 to 10.00 years. Conversely, from 2023 to 2025 the half-maximum age rises while the curve-weighted mean age falls. The ascending limb and older-age tail therefore move in different directions. This figure connects the detailed annual panels to the reference-point results: the age at which fish begin entering the fishery and the relative exposure of older fish carry different information. Its mean-age measure weights selectivity equally across model ages 1–15, with age 15 representing the plus group; population abundance and catch composition are excluded from that shape index.

The reference-rate comparison makes the dependence on age selection explicit (Figure 73). Under fixed biology, each curve has its own fully selected F35% rate, the fishing-mortality scalar that reduces lifetime spawning output per recruit to 35% of the unfished level. Later exposure can allow more spawning before capture and therefore support a higher fully selected rate at the same spawning-per-recruit target. However, the full curve, including its older-age tail, determines this response. The high 2019 F35% illustrates how a reference scalar can rise sharply under a particular age pattern. Such an increase describes the rate permitted under that pattern; it provides no independent evidence of increased stock productivity or a larger sustainable catch.

Two distinctions are essential when interpreting an FMSY proxy against selected age. First, F35% is a spawning-per-recruit proxy for FMSY, whereas FMSY itself depends on the equilibrium yield and recruitment relationship. The historical FMSY comparison and this F35% diagnostic therefore represent different reference quantities. Second, fully selected F is a scalar: fishing mortality at each age equals that scalar multiplied by selectivity at that age. Comparisons among years require the same selectivity normalization and the corresponding age-specific mortality pattern. The scatterplot uses a selectivity-weighted age index over ages 1–10, whereas its spawning-per-recruit calculation includes ages 1–14 and 15+, fixed natural mortality, maturity and the selected projection spawning weights, and quarter-year spawning timing. Its age index also differs from the ages 1–15 index in the preceding figure and from the abundance-weighted age of selected fish. It is a compact descriptor of curve shape, and a common mean selected age can accompany different reference rates. The complete selectivity curve and resulting catch and spawning effects provide the appropriate basis for interpreting the FMSY proxy and comparing harvest specifications.

8 Risk table and ABC recommendation

The author risk evaluation retains all four categories at Level 1 – Normal (Table 55). The ecosystem and fishery observations are summarized below. Working recommendations remain subject to author scientific evaluation and Plan Team, SSC and Council review. The Level 1 evaluation supports no reduction from maximum permissible ABC.

Table 55: 2026 risk-category scores and supporting summaries. Assessment-related and fishery-informed stock evaluations are Level 1 – Normal; population dynamics and ecosystem evaluations draw on the synthesis by Elizabeth Siddon and Kalei Shotwell.
Considerations
Assessment-related Population Dynamics Ecosystem Fishery-informed Stock
Level 1 – Normal Level 1 – Normal Level 1 – Normal Level 1 – Normal
Model developments improved fitting, with minor implications for stock status and projected ABC/OFL. Egg and larval abundance was low; later prey conditions were favorable and cannibalism was low. Cool conditions, abundant prey and improving adult condition indicated favorable ecosystem conditions. A-season fishing appeared good; later B-season fishing was farther north than normal, with limited desirable sizes.

8.1 Assessment-related considerations

Model 26.0 (Rceattle) is the adopted assessment model and main proposal for Tier 3 calculations and specifications. The alternative models examine how the assessment responds to changes in its structure and treatment of annual selectivity variation. Comparisons with Models 23.0 and 23.2 connect the current assessment to the previous formulation and help distinguish the effects of updated observations from changes in model structure. The split-fishery alternatives test whether separate selectivity patterns for the Foreign fishery in 1964–1990 and the Modern domestic fishery from 1991 onward better represent the fishing history. Further comparisons vary the constraint on declining selectivity and the treatment of year-to-year changes in selectivity.

Model 26.1.2 provides the principal sensitivity to these choices. Its underlying marginal formulation estimates the variability of Modern fishery selectivity while accounting for annual selectivity effects. The conditional comparison presented here fixes the Foreign and Modern process standard deviations at their selected full-data values and estimates the remaining parameters and annual selectivity effects. This configuration fits the Modern fishery age compositions more closely than Model 26.0, while larger discrepancies remain in the Foreign period. The result identifies a potential benefit of separating the fisheries, alongside a trade-off in how the model represents the earlier observations.

The Model 26.1.2 retrospective analysis asks whether estimates change as the most recent observations are successively removed. Each shortened-data fit holds the process standard deviations fixed and is compared with a full-data fit using the same conditional estimation method. This matching reference makes the retrospective differences interpretable within the fixed-SD configuration. The diagnostic therefore describes stability when the assumed magnitude of annual selectivity variation is held constant. Re-estimating that variation in each shortened dataset could change the retrospective pattern, and uncertainty in the process standard deviations remains outside this comparison. Improved fits to the Modern observations consequently provide one part of the model evaluation; broader retrospective reliability requires evidence across the relevant estimation choices. Model 26.0 remains the basis for the Tier 3 specifications, with Model 26.1.2 used to assess sensitivity to fishery structure and selectivity assumptions.

8.2 Population dynamics risk summary

Population dynamics risk is Level 1 – Normal. Cold spring conditions coincided with low egg and larval abundance; temperature-dependent timing complicates interpretation of these early-life indices. Southeastern Bering Sea (SEBS) age-0 abundance was also low. Above-average late-summer large copepod abundance, lipid-rich copepods and euphausiids, and above-average SEBS age-0 energy density indicate favorable feeding and potential survival through the first winter. Northern Bering Sea (NBS) age-0 energy density was below average, while adult-pollock cannibalism was low overall; age-1 specificity remains unverified. The regional contrasts and supporting evidence are described in Section 11.1 within Section 11.

8.3 Environmental and ecosystem risk summary

The environmental and ecosystem synthesis supports a Level 1 – Normal ecosystem score. Following the warm period of 2014–2021 and near-average thermal conditions in 2022–2025, the EBS shelf shifted to cool conditions in 2026. The expanded cold pool, abundant lipid-rich prey and improving adult condition provide favorable context for juvenile and adult pollock. Increased pollock biomass may increase competition; prey and condition indicators suggest adequate food, while the effects of increasing sablefish abundance remain a research question. Section 11 presents the detailed distribution, environmental, prey, competitor and predator evidence, including conditions for later juveniles and adults in Section 11.2. These category scores support the recommendation for no reduction from maximum permissible ABC.

8.4 Fishery-informed Stock Considerations

Fishing conditions differed between the two seasons. The observer data indicate that A-season fishing in 2026 appeared good. Later in the B-season, fishing occurred farther north than normal, and pollock of desirable sizes were limited. The late-season observations therefore qualify the favorable A-season picture and identify changes in where fishing occurred and the sizes available to the fishery.

We retain the Level 1 – Normal score for fishery-informed stock considerations. This score reflects the author’s qualitative assessment of fishing conditions across the year. The observations provide context for interpreting fishery performance; their implications for stock-wide abundance remain uncertain. A standardized comparison of fishing locations, effort and size composition would help distinguish changes in fishery availability from changes in overall stock abundance.

8.5 Ecosystem and Socioeconomic Profile development

Development of the EBS pollock Ecosystem and Socioeconomic Profile (ESP) continues alongside the assessment (Shotwell et al. 2026). The archived September 2026 development report supplies exploratory background, and the AI-assisted draft appears as Appendix B. The 2026 Eastern Bering Sea Ecosystem Status Report describes an external Dynamic Structural Equation Modeling (DSEM) analysis that identified sea ice extent, sea surface temperature (SST) and summer large copepods as indicators with statistically supported relationships to age-1 recruitment (Siddon 2026). The exploratory Rceattle DSEM pilot in the appendix uses late-summer SST and cold-pool extent as two environmental proxies. Its scope supports a separate assessment of those proxies. Evaluating all three external relationships within Rceattle requires additional testing.

The first application of DSEM has been completed as a draft in the ESP draft. Development and implementation of an integrated version within Rceattle continue from the work presented in the September 2026 development document (Ianelli et al. 2026). We see the Ecosystem Status Report (ESR), the ESP, and integration of ecosystem information within the full assessment model as logical applications of ecosystem-based methods for providing informed catch advice to the Council.

Since all four categories are Level 1 – Normal, we recommend no reduction from maximum permissible ABC.

9 Status determination

Under the Magnuson–Stevens Fishery Conservation and Management Act, stock status is evaluated for overfishing, an overfished condition, and the risk of approaching an overfished condition.

For Tier 3, B35% is the BMSY proxy. MSST is evaluated using the biomass and projection tests below. Alternative 6 fishes at the OFL rate in every projected year. Alternative 7 fishes at the maximum-ABC rate in 2027–2028 and the OFL rate from 2029 onward.

Overfishing in 2025. Catch of 1,326,215.61 t was below the specified Bering Sea subarea OFL of 2,957,000 t. Thus, the stock was not subjected to overfishing in 2025.

Overfished in 2026. Biomass below half B35% indicates an overfished condition; biomass above B35% indicates the stock is above MSST. Between those levels, status depends on Alternative 6 biomass in 2036: below B35% indicates an overfished condition; otherwise, the stock is above MSST. Current biomass is 3.057 million t for Model 26.0 and 3.065 million t for the Early-late fishery split Model 26.1.2 sensitivity, above their respective B35% values of 2.155 and 2.177 million t. Both therefore indicate the stock is not overfished; the 2036 test is unnecessary.

Approaching an overfished condition. Under Alternative 7, 2028 biomass below half B35% indicates an approaching overfished condition; biomass above B35% indicates it is not approaching that condition. If that biomass falls between half B35% and B35%, use Alternative 7 biomass in 2038 for the long-term test. Biomass below B35% in that long-term test indicates an approaching overfished condition. Projected 2028 biomass is 3.123 million t for Model 26.0 and 3.179 million t for Model 26.1.2, both above B35%. Neither model indicates an approaching overfished condition; the 2038 test is unnecessary.

These comparisons use deterministic historical-mean recruitment. Assessment conclusions and adopted catch specifications remain separate from final NMFS status determinations.

Comparison of Model 26.0 and the sensitivity analysis
Quantity Year / basis Model 26.0 26.1.2 Early-late fishery split
Estimated female spawning biomass 2026 3,057,000 3,065,000
BMSY proxy: B35% Reference point 2,155,000 2,177,000
Lower status boundary: half B35% Reference point 1,078,000 1,088,000
Alternative 6 female spawning biomass 2036 2,263,000 2,288,000
Alternative 7 female spawning biomass 2028 3,123,000 3,179,000
Alternative 7 female spawning biomass 2038 2,263,000 2,288,000
Maximum ABC: expected-catch scenario 2027 1,896,000 1,855,000
OFL: expected-catch scenario 2027 2,328,000 2,269,000
Maximum ABC: expected-catch scenario 2028 1,968,000 1,958,000
OFL: expected-catch scenario 2028 2,422,000 2,399,000
Biomasses are female spawning biomass at April 1, in tons. B35% is the Tier 3 BMSY proxy. The intermediate MSST tests use Alternative 6 in 2036 and Alternative 7 in 2038; they are unnecessary here because current and two-year Alternative 7 biomass exceed B35%.
Future ABC/OFL rows use each model’s expected-catch scenario, with 1,375,000 t catch in each of 2027 and 2028. They are model-based maxima, separate from adopted specifications. Model 26.0 (Rceattle) is the adopted assessment model and main proposal for Tier 3 calculations and specifications; Model 26.1.2 is the sensitivity analysis. Values are rounded to the nearest 1,000 t; source exports retain their original precision. Projections condition on the revised fitted population, fixed biology and constant historical-mean recruitment.

10 F limit

Following section 4.15 of the assessment guidelines, F limit is reverse-engineered as the annual fishing mortality that would have produced the previous year’s OFL using the recommended model’s estimated population for that year. For this 2026 assessment, the calculation therefore uses the adopted 2025 Bering Sea pollock OFL of 2.957 million t (National Marine Fisheries Service (2025)) and the Model 26.0 beginning-of-year 2025 numbers at age, fishery weights, natural mortality and realized selectivity.

Solving the annual Baranov catch equation gives F limit = 0.787 per year on the maximum-F-across-ages scale used in this report, with the maximum at age 6. The equivalent scalar on Rceattle’s native mean-normalized selectivity scale is 0.439 per year. Both scalings give the same fishing mortality at age and reproduce the adopted 2025 OFL. This calculation holds the fitted population and biological inputs fixed while changing fishing mortality.

The calculation finds the value of FlimitF_{\mathrm{limit}} satisfying

C2025OFL=∑a=115+Na,2025wa,2025fisheryFlimitsa,2025*Ma,2025+Flimitsa,2025*[1−exp{−(Ma,2025+Flimitsa,2025*)}].(1) C^{\mathrm{OFL}}_{2025}= \sum_{a=1}^{15+} N_{a,2025}\,w^{\mathrm{fishery}}_{a,2025} \frac{F_{\mathrm{limit}}\,s^{*}_{a,2025}} {M_{a,2025}+F_{\mathrm{limit}}\,s^{*}_{a,2025}} \left[1-\exp\!\left\{-\left(M_{a,2025}+F_{\mathrm{limit}}\,s^{*}_{a,2025}\right)\right\}\right]. \qquad(1)

Here NN is beginning-of-year abundance, wfisheryw^{\mathrm{fishery}} is fishery weight-at-age, MM is annual natural mortality, and s*s^{*} is the fitted selectivity curve rescaled to a maximum of one. Thus FlimitF_{\mathrm{limit}} is the maximum annual fishing mortality across ages. The sum includes ages 1–15+. Abundance in millions of fish and weight in kg give catch in thousand tons.

11 Ecosystem considerations

A draft Ecosystem and Socioeconomic Profile (ESP) is presented in Appendix B. It brings together indicators of pollock habitat, food-web conditions and fishery performance to provide context for the assessment. The ESP complements the population model by organizing evidence about processes that can affect year-class strength, fish growth and the distribution of fish available to surveys and the fishery. This broader perspective helps interpret changes in abundance and age composition alongside the environmental conditions experienced by successive cohorts.

The draft 2026 Eastern Bering Sea Ecosystem Status Report provides the environmental and food-web evidence summarized here (Siddon 2026). In 2026, cool spring conditions and an extensive cold pool coincided with low egg, larval and southeastern Bering Sea age-0 abundance. At the same time, favorable zooplankton abundance and lipid content, together with above-average southeastern Bering Sea age-0 energy density, indicated good feeding conditions for surviving juveniles. These contrasting signals emphasize the importance of timing, region and life stage: low early abundance and favorable later feeding conditions can occur within the same year. Their implications for recruitment depend on survival through the subsequent winter and later juvenile stages.

The following subsections connect these observations to pollock population processes. The first considers environmental conditions, prey, competitors and predators affecting eggs, larvae and early juveniles. The second addresses the distribution, feeding conditions and condition of later juveniles and adults, including how temperature and vertical habitat use can affect survey availability. Together, these indicators help distinguish changes in population abundance from changes in where fish occur and how effectively surveys sample them. The synthesis informs interpretation of the assessment and the risk-category evaluation summarized in Section 8; the individual indicators provide complementary evidence rather than a direct forecast of recruitment or an automatic adjustment to catch advice.

11.1 Ecosystem impacts of EBS pollock population dynamics

Environmental Processes

A very weak winter Aleutian Low in 2025/2026 brought cool Arctic air across the EBS (Lemagie and Wang 2026). Sea ice extent remained above average for six weeks during March–April 2026 (Thoman 2026). The resulting 2°C cold pool was approximately 150% larger than in 2025 and the fifth-largest during 1982–2026; the 0°C cold pool was the largest since 2013 (Rohan and Barnett 2026). Sea surface temperatures in the SEBS were colder than in 2025, especially during January–April, and remained below average for most of the year (Lemagie and Callahan 2026). In May 2026, spring winds favored Ekman transport off the shelf, influencing larval dispersal trajectories (Hennon 2026).

Prey

Large diatom anomalies were above average during 2023–2025 (Ostle and Batten 2026), and spring 2026 chlorophyll-a concentrations were average to high across the NBS and SEBS (Gann et al. 2026). These records suggest favorable prey-production conditions in their respective periods. Increased surface phosphate and a deeper mixed layer in 2024 imply wind mixing, larger phytoplankton cells, shorter food chains and more efficient energy transfer to juvenile fish (Gann 2026).

The spring Rapid Zooplankton Assessment indicated adequate small copepod abundance, with above-average large copepod abundance by late summer (Kimmel et al. 2026). Euphausiid abundance increased from 2025 (Levine et al. 2026; Spear et al. 2026). Copepod and euphausiid lipid content in the SEBS were both above average in 2026, indicating good prey quality for pelagic juveniles (Pinger et al. 2026).

Spring larval abundance and egg numbers were low, as was the larval condition ratio. Such observations are typical of cold spring conditions over the shelf, and temperature-dependent seasonal timing complicates their interpretation (Siddon 2026). SEBS age-0 abundance was low (Andrews, Domke, Murphy, Spear, et al. 2026), and age-0 energy density was above average (Page et al. 2026). The suggested increase in age-1 abundance in this juvenile-survey comparison remains unverified. Length–weight residuals for small pollock (100–250 mm) in the EBS survey improved to just below the long-term mean (Prohaska and Rohan 2026). In the NBS, age-0 abundance was average (Andrews, Domke, Murphy, Spear, et al. 2026) and energy density was below average (Page et al. 2026).

Competitors

Pelagic forager biomass increased from 2025 to 2026 to above its long-term mean, largely driven by a 58% increase in pollock biomass (Siddon 2026, 7–9). Above-average zooplankton quantity and quality moderate concerns about competition for prey among young pollock. SEBS jellyfish biomass remained average (Buser 2026) to below average (Domke et al. 2026). NBS jellyfish biomass continued its slow decline since 2023 and remained just above the time-series mean (Domke et al. 2026).

Pacific herring and capelin biomass were below average in both the NBS and SEBS (Andrews, Domke, Murphy, Dimond, et al. 2026). Bristol Bay sockeye salmon continued to decline from peak 2021/2022 levels (Cunningham et al. 2026). Strong 2020 and 2022 sablefish year classes contributed to a growing, aging population that could compete for pelagic juvenile prey; direct evidence for that competition remains unavailable (Siddon 2026).

Predators

Adult pollock diets consisted primarily of copepods and euphausiids, with a low overall proportion of cannibalism in 2026 (Aydin 2026). CNRG estimates show that age-1 predation mortality declined from 2025, while mortality due to cannibalism remained slightly above its long-term mean. The biomass of pollock consumed by conspecifics was approximately average and lower than in 2024 and 2025 (Holsman et al. 2026). Adult Bristol Bay sockeye salmon, which prey on juvenile pollock, decreased from 2025 (Cunningham et al. 2026).

Northern fur seal pup weights at St. Paul Island exceeded the average by more than one standard deviation, and maternal trip durations were the shortest in the time series. These indicators suggest high foraging success near the island. Age-0 pollock and herring had the highest frequency of occurrence in the September 2025 fur-seal diet samples; analysis of September 2026 samples was ongoing in the draft (McHuron et al. 2026). The apex predator guild increased from 2025, driven by a 17% increase in Pacific cod, and remained below its long-term mean (Siddon 2026, 7–9). This guild level suggests low predation pressure on juvenile pollock (Siddon 2026).

11.2 Ecosystem considerations for later juveniles and adults

Distribution

Pollock biomass estimated by the standard bottom-trawl survey increased approximately 50% from 2025 to 2026, alongside a pronounced spatial pattern associated with the extensive cold pool. Adult pollock occurred primarily outside bottom waters colder than 2°C, with concentrations along the northwestern outer shelf (Siddon 2026). The cold pool therefore delineated the near-bottom habitat occupied by much of the adult population during the survey. This pattern is relevant to interpreting the biomass increase because survey catches reflect both the number and size of fish present and their availability to bottom-trawl gear. The higher survey estimate and the concentration of adults along the cold-pool margin should be considered together when comparing years. The spatial association supports a role for temperature in shaping survey availability, while the contribution of redistribution to the biomass increase remains unresolved.

Environmental Processes

Bottom temperatures in 2026 were comparable to the historical cool years 1986, 1992, 2006 and 2010 (Siddon 2026). The large cold pool provided further evidence of cool bottom conditions (Rohan and Barnett 2026). Below-average SSTs characterized the SEBS, particularly during spring (Lemagie and Callahan 2026). Adult pollock condition was above its long-term mean (Prohaska and Rohan 2026). These temperature and condition patterns describe concurrent conditions; their causal relationship remains an interpretation.

Prey

Adult pollock diets continued to be dominated by copepods and euphausiids (Aydin 2026). Summer and late-summer euphausiid abundance increased from 2025 to 2026 (Levine et al. 2026; Spear et al. 2026), and above-average SEBS copepod and euphausiid lipid content provided lipid-rich prey (Pinger et al. 2026). Cannibalism formed a low proportion of adult pollock diets (Aydin 2026). CNRG estimates separately indicate slightly above-average mortality of age-1 pollock from cannibalism, with approximately average biomass consumed by conspecifics (Holsman et al. 2026).

Morphometric condition, measured as length–weight residuals, for large adult pollock (>250 mm) in the EBS survey increased from 2023 to 2026 to above the long-term mean. The NBS condition series extends through 2025, when large-pollock condition remained positive and continued the increasing trend observed since 2021 (Prohaska and Rohan 2026).

Competitors

The increase in pelagic forager biomass from 2025 to 2026 was primarily driven by pollock (Siddon 2026, 7–9), suggesting a potential increase in competition within the pollock population. Above-average prey quantity, prey quality and pollock length–weight residuals indicate adequate food resources. Increasing sablefish abundance represents potential competition for pelagic prey, with direct evidence still pending (Siddon 2026).

Predators

The apex predator guild, driven by Pacific cod, increased from 2025 and remained below its long-term mean (Siddon 2026, 7–9). This pattern suggests low predation pressure on pollock (Siddon 2026). These associations provide context for the stock; independent evidence is needed to establish the underlying mechanisms. The Plan Team requested further examination of ecosystem contributions to retrospective behavior alongside the direct data-influence tests.

12 Data gaps and research priorities

The 2026 assessment compares the separately fitted configurations and the Model 26.1.2 marginal-estimation sensitivity using their matching observations and conditional observation diagnostics. Model 26.0 posterior uncertainty, predictive observation checks and nine retrospective fits are complete. The Model 26.1.2 retrospective diagnostic uses fixed full-model process SDs and a conditional full 2026 reference. The two Model 26.0 simulation-retrospective experiments compare conditional biomass and recruitment revisions with the observed-data results (Section 6.3.1). Each experiment uses ten simulated datasets to examine biomass and recruitment revisions.

Additional age-1 BTS selectivity and BTS data-influence tests are outside the scope of this assessment (PT-02 and PT-05). The comparisons describe differences in retrospective patterns. The weight-at-age comparison in Section 4.1.3 retains the distinction between estimated schedules and uncertainty carried into population and projection outputs.

A high research priority is to refine the statistical treatment of length compositions and age observations from the fishery, bottom-trawl survey (BTS), and acoustic-trawl survey (ATS), together with paired Fourier-transform near-infrared spectroscopy (FT-NIR) and traditional morphological ageing (TMA) observations. A more statistically rigorous framework should account for sampling structure, ageing error, uncertainty in conversions between ageing methods, and dependence among observations derived from the same samples. This work should guide composition weighting and the integration of length and age information, with the resulting methods and uncertainty treatment carried into future model specifications.

The treatment of early fishery data should also be refined relative to more recent observations. Research should evaluate changes in sampling coverage, age and length information, and fishing practices across periods, and use those differences to inform selectivity assumptions and observation weights. Comparisons should assess how alternative treatments affect recruitment, biomass trends, and retrospective behavior.

Further development of random-effects models should address temporal variation in selectivity and other population or observation processes. Priorities include identifying which sources of variability the data can resolve, evaluating correlation across ages and years, and estimating process variation within a coherent framework. Simulation tests, retrospective analyses, and predictive checks should evaluate model performance and the propagation of uncertainty into stock status and catch projections.

The Ecosystem and Socioeconomic Profile (ESP) provides a basis for fuller implementation and use of dynamic structural equation models (DSEM). This work should develop and test hypothesized links among environmental conditions, prey, pollock condition, and recruitment, while accounting for observation uncertainty, missing years, and time lags. Evaluation should establish the stability and predictive value of these relationships and how ESP results can inform assessment interpretation, recruitment scenarios, and future model specifications.

Additional research questions include AVO uncertainty, the 2018 recruitment profile, and stock boundaries and connectivity.

13 Acknowledgements

We thank the scientifically trained observers and AFSC fisheries monitoring staff for their hard work and dedication. Survey staff contribute immensely through their diligence in collecting the samples that support this assessment, and their commitment under challenging circumstances is exceptional. We also thank the AFSC age-and-growth staff for their continued excellence in promptly processing these samples.

We thank the many colleagues who provided edits and suggestions to improve this document, particularly Dr. Cole Monnahan for his timely and thoughtful review.

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Tables

Table 1: Catch and adopted harvest limits for EBS pollock, 1964–2026 (round-weight metric tons). Catch from 1991 onward uses the catch estimates; the highlighted 2026 value is the selected annual model input, with the catch-data cutoff unspecified.
EBS catch and adopted harvest limits
Year OFL (t) ABC (t) TAC (t) Catch (t)
1964 — — — 174,792
1965 — — — 230,551
1966 — — — 261,678
1967 — — — 550,362
1968 — — — 702,181
1969 — — — 862,789
1970 — — — 1,256,565
1971 — — — 1,743,763
1972 — — — 1,874,534
1973 — — — 1,758,919
1974 — — — 1,588,390
1975 — — — 1,356,736
1976 — — — 1,177,822
1977 — 950,000 950,000 978,370
1978 — 950,000 950,000 979,431
1979 — 1,100,000 950,000 935,714
1980 — 1,300,000 1,000,000 958,280
1981 — 1,300,000 1,000,000 973,502
1982 — 1,300,000 1,000,000 955,964
1983 — 1,300,000 1,000,000 981,450
1984 — 1,300,000 1,200,000 1,092,055
1985 — 1,300,000 1,200,000 1,139,676
1986 — 1,300,000 1,200,000 1,141,993
1987 — 1,300,000 1,200,000 859,416
1988 — 1,500,000 1,300,000 1,228,721
1989 — 1,340,000 1,340,000 1,229,600
1990 — 1,450,000 1,280,000 1,455,193
1991 — 1,676,000 1,300,000 1,195,644
1992 1,770,000 1,490,000 1,300,000 1,390,299
1993 1,340,000 1,340,000 1,300,000 1,326,602
1994 1,590,000 1,330,000 1,330,000 1,329,352
1995 1,500,000 1,250,000 1,250,000 1,264,247
1996 1,460,000 1,190,000 1,190,000 1,192,781
1997 1,980,000 1,130,000 1,130,000 1,124,433
1998 2,060,000 1,110,000 1,110,000 1,102,159
1999 1,720,000 992,000 992,000 989,680
2000 1,680,000 1,139,000 1,139,000 1,132,710
2001 3,536,000 1,842,000 1,400,000 1,387,197
2002 3,530,000 2,110,000 1,485,000 1,480,774
2003 3,530,000 2,330,000 1,491,760 1,490,779
2004 2,740,000 2,560,000 1,492,000 1,480,552
2005 2,100,000 1,960,000 1,478,500 1,483,022
2006 2,090,000 1,930,000 1,485,000 1,488,031
2007 1,640,000 1,394,000 1,394,000 1,354,502
2008 1,440,000 1,000,000 1,000,000 990,578
2009 977,000 815,000 815,000 810,784
2010 918,000 813,000 813,000 810,186
2011 2,450,000 1,270,000 1,252,000 1,199,031
2012 2,474,000 1,220,000 1,200,000 1,205,214
2013 2,550,000 1,375,000 1,247,000 1,270,760
2014 2,795,000 1,369,000 1,267,000 1,297,417
2015 3,330,000 1,637,000 1,310,000 1,321,574
2016 3,910,000 2,090,000 1,340,000 1,352,681
2017 3,640,000 2,800,000 1,345,000 1,359,181
2018 4,797,000 2,592,000 1,364,341 1,379,288
2019 3,914,000 2,163,000 1,397,000 1,409,346
2020 4,085,000 2,043,000 1,425,000 1,367,236
2021 2,594,000 1,626,000 1,375,000 1,376,258
2022 1,469,000 1,111,000 1,111,000 1,105,419
2023 3,381,000 1,910,000 1,300,000 1,310,592
2024 3,162,000 2,313,000 1,313,580 1,311,261
2025 2,957,000 2,417,000 1,389,000 1,326,216
2026 2,496,000 2,036,000 1,389,500 1,312,505
Catch for 1991–2026 uses the revised annual estimates. Model inputs use the same totals at full precision, converted to thousand tons. Pre-1991 catch and adopted harvest limits retain their previous sources. Dashes mean unavailable.
All Bering Sea pollock retained/discarded, gear and sector records are summed once. Explicit Bogoslof (518) and outside-stock area codes are excluded. The 23 records with blank reporting-area codes in 1998 retain their Bering Sea classification and contribute 83,077.58 t. The year-by-year reconciliation is in the catch-revision table.
The 2026 CSV total is 1,312,504.580845496 t and is used as the annual input under the author’s instruction. The CSV supplies no within-year catch cutoff; the author has confirmed this CSV as the correct annual input version. The previous 1,310,000-t forecast and October 17 catch-to-date are archived in the revision record. Annual source totals.
Table 2: Selected management and monitoring milestones affecting the EBS pollock fishery, 1977–2017. Dates distinguish Council recommendations, enactment, voluntary programs and regulatory implementation. BSAI- or GOA-wide scope is stated where applicable; the table is selective rather than a complete regulatory history.
Historical pollock management and monitoring measures
Year Action stage Measure and scope Sources
1977 Implemented Preliminary BSAI fishery management plan (FMP), including closure areas. SAFE 2024; History 1997
1982 Implemented BSAI groundfish FMP implemented; Chinook salmon bycatch limits established for foreign trawlers. SAFE 2024; History 1997
1984 Implemented BSAI groundfish optimum yield capped at 2 million t; Chinook salmon bycatch limits for foreign trawling reduced. SAFE 2024; History 1997
1990 Implemented Domestic observer program and associated data reporting began. SAFE 2024; NOAA history
1992 Implemented Pollock allocations under the Western Alaska Community Development Quota (CDQ) program began. SAFE 2024
1993–1994 Donation program Prohibited Species Donation Program established in 1993; voluntary salmon donations in 1994 are reported in the accepted assessment history. Council overview; SAFE 2024
1994 Council recommendation Council recommended minimum codend mesh/design standards; an implemented NMFS mesh rule is not established by the reviewed sources. History 1997; Gear review
1994 Reporting NMFS began publishing individual-vessel bycatch rates online. SAFE 2024; History 1997
1994–1995 Implemented Emergency Chum Salmon Savings Area in 1994; permanent chum savings-area provisions under Amendment 35 in 1995, alongside the historical Chinook closure/trigger regime. 2023 notice history; SAFE 2024
1998 Implemented Amendment 49 improved retention/utilization requirements for pollock and Pacific cod took effect January 3. Amendment 49
1998 Enacted American Fisheries Act (AFA) enacted, establishing the framework for sector allocations and fishery cooperatives. SAFE 2024; AFA rule
1999 Implemented AFA provisions implemented for catcher/processors. SAFE 2024; AFA rule
1999 Emergency rule Temporal/spatial pollock dispersal measures and trawl exclusion zones around selected Steller sea lion rookeries and haulouts in BSAI and GOA. 1999 emergency rule
2000 Implemented AFA provisions implemented for the remaining catcher-vessel and mothership sectors. SAFE 2024; AFA rule
2001 Voluntary Pollock industry began the chum salmon rolling-hotspot program. 2023 notice history; SAFE 2024
2002 Voluntary Pollock industry began the Chinook salmon rolling-hotspot program. 2023 notice history; SAFE 2024
2005 Council action Council selected Amendment 84 in October to provide a salmon bycatch intercooperative agreement (ICA) alternative to fixed savings-area closures. Amendment 84
2006 Exempted fishing The B-season exempted fishing permit tested the ICA/rolling-hotspot approach before general regulatory implementation. Amendment 84
2007 Implemented Amendment 84 regulations, effective November 28, exempted pollock vessels participating in an approved salmon bycatch ICA from specified savings-area closures. Amendment 84
2010–2011 Rule / program Amendment 91 final rule effective September 29, 2010; Chinook PSC limits, incentive plan agreements (IPAs), performance standards and enhanced monitoring operated in the 2011 fishery. Amendment 91
2015 Council action Council took final action on Amendment 110 in April, recommending linked Chinook/chum avoidance measures and abundance-based Chinook limits. Amendment 110
2016 Implemented Amendment 110 final rule published June 10, effective July 11. It strengthened IPAs and changed pollock seasonal allocations to 45% A season / 55% B season. Amendment 110
2017 First index year First fishing year informed by the Amendment 110 three-system abundance index in 2016. Low-abundance limits apply when the index is at or below 250,000 Chinook salmon. Amendment 110
Historical entries were checked against accepted 2024 SAFE Table 4 (p. 63) and the linked primary sources. The 1994 codend item is a Council recommendation; the reviewed sources do not establish NMFS implementation. The 2005 Amendment 84 action preceded exempted fishing and 2007 regulations. Council action and rule effective dates are distinct.
The 45% / 55% allocation in the 2016 rule concerns pollock, distinct from Chinook PSC apportionments. Continuing and dated 2026 measures are described in Fishery and management history. Age-estimation and survey developments are documented in their respective report sections; they are not listed here as regulatory implementations.
CSV; Markdown; row-by-row verification and corrections. Original source records remain unchanged.
Table 3: EBS pollock catch by reporting area and season, 1991–2026 (tons). Southeast (SE) comprises NMFS areas 520–539; Northwest (NW) comprises areas 500–517 and 519. Area 518 (Bogoslof) is excluded. A and B group records with week-ending dates before June 1 and from June 1 onward, respectively. The catch data extend through October 17, 2026. Only the 1998 records included catch without an area; this catch is allocated between NW and SE in proportion to reported catch within each season. Totals include retained and discarded catch; values are rounded to whole tons.
Year NW A NW B SE A SE B NW SE A B Total
1991 297,202 356,353 12,191 529,917 653,555 542,109 309,393 886,271 1,195,664
1992 454,947 375,612 101,597 458,143 830,559 559,741 556,544 833,755 1,390,299
1993 475,143 619,287 93,013 139,160 1,094,429 232,173 568,156 758,446 1,326,602
1994 586,105 566,470 11,026 165,751 1,152,575 176,777 597,131 732,221 1,329,352
1995 600,499 571,807 3,631 88,310 1,172,306 91,941 604,129 660,117 1,264,247
1996 549,297 537,545 1,804 104,135 1,086,843 105,939 551,101 641,680 1,192,781
1997 557,106 262,784 2,363 302,180 819,889 304,544 559,469 564,964 1,124,433
1998 515,420 443,514 1,632 141,593 958,934 143,226 517,052 585,107 1,102,159
1999 414,030 368,953 4,139 202,558 782,983 206,698 418,169 571,511 989,680
2000 439,023 400,154 19,363 274,170 839,177 293,532 458,386 674,324 1,132,710
2001 444,565 517,412 108,013 317,207 961,977 425,220 552,578 834,619 1,387,197
2002 561,061 599,272 36,693 283,749 1,160,334 320,442 597,754 883,022 1,480,776
2003 446,152 487,039 151,465 406,123 933,191 557,588 597,617 893,162 1,490,779
2004 556,469 533,538 50,661 339,883 1,090,008 390,544 607,130 873,422 1,480,552
2005 476,970 325,184 120,320 560,548 802,154 680,868 597,290 885,732 1,483,022
2006 585,507 241,700 18,789 642,034 827,207 660,824 604,297 883,734 1,488,031
2007 505,306 222,943 62,504 563,748 728,249 626,253 567,811 786,691 1,354,502
2008 358,936 123,762 44,801 463,079 482,698 507,880 403,738 586,840 990,578
2009 247,944 110,307 81,575 370,957 358,252 452,532 329,520 481,264 810,784
2010 124,670 130,443 199,011 356,061 255,114 555,072 323,681 486,505 810,186
2011 401,755 346,128 102,252 348,897 747,882 451,149 504,007 695,024 1,199,031
2012 380,373 238,497 104,926 481,418 618,870 586,344 485,299 719,915 1,205,214
2013 415,014 280,652 94,763 480,331 695,667 575,094 509,777 760,983 1,270,760
2014 469,973 388,267 50,465 388,712 858,240 439,177 520,438 776,979 1,297,417
2015 267,095 429,153 258,574 366,752 696,248 625,326 525,669 795,905 1,321,574
2016 458,044 709,028 81,531 104,078 1,167,072 185,609 539,576 813,106 1,352,681
2017 544,028 633,993 37,730 143,430 1,178,021 181,159 581,758 777,423 1,359,181
2018 598,533 450,160 3,842 326,753 1,048,692 330,595 602,375 776,913 1,379,288
2019 614,949 487,217 2,649 304,532 1,102,166 307,181 617,598 791,749 1,409,346
2020 560,438 299,978 85,717 421,102 860,416 506,820 646,156 721,080 1,367,236
2021 554,774 469,234 56,779 295,470 1,024,009 352,249 611,554 764,704 1,376,258
2022 487,216 411,573 9,018 197,610 898,790 206,629 496,235 609,184 1,105,419
2023 568,455 319,251 11,335 411,552 887,705 422,887 579,789 730,803 1,310,592
2024 530,902 347,432 55,087 377,840 878,334 432,927 585,989 725,272 1,311,261
2025 445,959 270,015 157,475 452,767 715,974 610,242 603,434 722,782 1,326,216
2026 528,440 205,467 75,601 458,034 733,908 533,635 604,041 663,501 1,267,543
Table 4: Retained and discarded EBS pollock catch by reporting area, 1991–2026 (tons), from annual catch-accounting data. Southeast (SE) comprises NMFS areas 520–539; Northwest (NW) comprises areas 500–517 and 519. Area 518 (Bogoslof) is excluded. Discarded percentage equals discarded catch divided by total catch. Values are rounded to whole tons; 2026 estimates are preliminary.
Year NW Discarded SE Discarded NW Retained SE Retained Total Discarded %
1991 66,792 48,257 586,763 493,852 1,195,664 9.6
1992 71,194 57,578 759,365 502,163 1,390,299 9.3
1993 83,986 26,100 1,010,443 206,073 1,326,602 8.3
1994 88,098 16,084 1,064,476 160,693 1,329,352 7.8
1995 87,492 9,715 1,084,813 82,226 1,264,247 7.7
1996 71,368 4,838 1,015,474 101,100 1,192,781 6.4
1997 71,032 22,557 748,858 281,986 1,124,433 8.3
1998 14,291 1,581 944,511 141,777 1,102,159 1.4
1999 26,912 1,912 756,071 204,786 989,680 2.9
2000 19,678 1,942 819,499 291,591 1,132,710 1.9
2001 14,874 2,450 947,103 422,770 1,387,197 1.2
2002 19,430 1,441 1,140,904 319,002 1,480,776 1.4
2003 13,795 2,959 919,397 554,629 1,490,779 1.1
2004 20,380 2,781 1,069,628 387,763 1,480,552 1.6
2005 14,838 2,586 787,316 678,282 1,483,022 1.2
2006 11,877 3,677 815,330 657,147 1,488,031 1.0
2007 12,334 3,769 715,915 622,484 1,354,502 1.2
2008 5,968 1,643 476,730 506,237 990,578 0.8
2009 4,014 1,936 354,238 450,596 810,784 0.7
2010 2,490 1,270 252,623 553,802 810,186 0.5
2011 3,444 1,376 744,438 449,773 1,199,031 0.4
2012 4,080 1,190 614,791 585,154 1,205,214 0.4
2013 4,084 1,225 691,582 573,869 1,270,760 0.4
2014 12,556 1,786 845,684 437,391 1,297,417 1.1
2015 7,055 2,418 689,193 622,907 1,321,574 0.7
2016 8,124 1,036 1,158,948 184,574 1,352,681 0.7
2017 6,848 1,356 1,171,173 179,803 1,359,181 0.6
2018 9,170 2,005 1,039,523 328,590 1,379,288 0.8
2019 7,126 1,979 1,095,040 305,202 1,409,346 0.6
2020 9,363 2,450 851,053 504,370 1,367,236 0.9
2021 12,379 1,534 1,011,629 350,715 1,376,258 1.0
2022 9,898 3,538 888,891 203,091 1,105,419 1.2
2023 10,219 4,685 877,486 418,201 1,310,592 1.1
2024 12,935 4,131 865,399 428,796 1,311,261 1.3
2025 6,355 899 709,618 609,343 1,326,216 0.5
2026 5,815 3,182 769,440 534,068 1,312,505 0.7
Table 5: EBS pollock fishery catch-at-age estimates, 1964–2025 (million fish). Ages 15 and older are pooled as 15+. Catch numbers are calculated from assessment proportions, annual fishery weights at age and catch biomass where complete annual numbers are unavailable. Age-specific values are rounded to 0.1 million fish; All ages totals are rounded to the nearest million fish.
Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15+ All ages
1964 8.3 34.8 54.6 63.8 31.5 88.5 39.8 8.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 330
1965 7.2 7.8 103.3 278.4 68.2 17.0 16.4 7.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 506
1966 16.9 100.2 34.2 250.2 157.8 14.4 15.7 6.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 596
1967 14.1 164.0 859.9 130.6 238.2 56.6 17.1 8.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1,489
1968 57.3 310.9 244.1 815.5 186.9 53.2 63.7 9.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1,741
1969 33.6 182.6 1051.1 722.5 248.2 5.3 27.8 17.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2,289
1970 730.1 1109.2 1743.2 823.0 159.5 51.9 25.9 14.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4,658
1971 766.6 229.0 1278.9 858.5 1272.7 123.6 81.2 22.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4,633
1972 155.0 747.6 1724.5 1381.2 578.7 227.0 86.2 31.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4,931
1973 36.3 327.2 396.1 861.1 659.1 450.3 250.5 181.5 81.4 14.7 1.8 0.5 0.1 0.5 0.0 3,261
1974 117.7 2558.9 945.7 269.0 361.3 195.1 124.9 105.3 103.3 43.5 17.7 4.6 4.6 0.8 0.7 4,853
1975 34.3 602.7 2774.6 213.3 56.7 106.6 102.1 55.6 32.7 23.0 5.7 2.3 0.4 0.5 0.0 4,010
1976 0.6 357.3 1351.8 909.8 89.7 41.4 57.3 66.5 51.7 25.5 11.8 8.0 2.1 0.0 0.0 2,973
1977 104.3 685.8 916.8 664.3 238.5 53.0 19.5 28.1 22.5 18.0 9.3 4.6 3.4 0.7 0.2 2,769
1978 29.4 455.2 752.9 638.6 368.2 99.7 28.8 17.3 19.7 15.8 11.1 4.3 1.8 0.5 0.2 2,444
1979 89.6 479.6 635.7 371.0 346.6 190.3 49.7 22.7 31.7 24.3 15.6 7.0 2.6 0.5 0.5 2,267
1980 9.0 424.0 754.9 406.7 231.2 193.5 76.8 34.5 19.9 21.9 23.3 14.6 7.1 2.3 1.1 2,221
1981 0.6 75.8 1062.5 669.3 238.2 107.9 54.2 31.1 16.9 9.8 7.9 4.8 1.6 0.7 0.3 2,282
1982 4.5 24.0 152.6 1108.4 399.3 98.1 34.0 34.1 20.4 8.6 5.1 3.0 1.8 0.7 0.3 1,895
1983 5.2 121.3 161.4 320.2 835.8 223.3 42.4 25.3 20.3 11.4 7.8 5.0 3.6 1.8 0.4 1,785
1984 1.9 41.8 80.8 392.7 448.3 596.3 122.0 32.4 22.9 14.3 6.5 2.3 2.7 1.5 1.8 1,768
1985 2.4 50.9 351.3 112.2 337.0 296.3 408.4 103.6 33.7 23.8 22.9 9.8 8.7 3.7 4.7 1,770
1986 2.8 78.5 84.2 683.0 195.4 345.0 202.5 195.5 54.5 13.9 3.0 2.4 0.2 1.1 0.0 1,862
1987 0.0 16.3 91.9 63.9 340.5 114.4 100.9 74.7 203.6 44.5 31.9 17.7 23.8 5.0 6.6 1,136
1988 0.0 9.7 410.9 381.6 228.2 492.7 203.4 95.0 35.5 87.6 16.5 9.2 3.4 5.0 5.6 1,984
1989 0.0 4.3 49.7 134.4 406.8 150.4 516.1 86.9 93.6 29.2 116.4 9.8 3.6 2.3 5.3 1,609
1990 1.4 36.1 62.2 239.8 219.3 522.1 141.2 402.6 71.8 111.4 9.9 65.6 9.3 5.1 10.1 1,908
1991 0.7 112.9 43.8 90.3 153.9 184.4 497.5 78.1 288.0 28.9 144.1 18.7 91.2 22.8 53.3 1,808
1992 1.1 84.7 675.8 130.1 79.6 108.7 133.8 253.6 102.3 147.0 58.0 46.3 13.4 43.8 34.5 1,913
1993 0.1 7.4 260.5 1146.7 103.0 66.2 66.4 56.5 86.2 21.2 32.7 12.4 13.5 6.8 16.1 1,895
1994 0.7 30.2 55.1 361.2 1059.7 175.7 53.5 19.1 13.1 20.2 9.7 9.4 7.6 4.0 8.3 1,827
1995 0.0 0.5 72.9 146.8 395.5 761.1 136.3 34.6 12.3 7.5 17.5 5.0 5.8 1.7 8.9 1,606
1996 0.0 21.7 48.1 71.8 161.0 361.9 481.7 184.6 33.6 13.4 7.9 8.8 4.3 5.8 5.3 1,410
1997 1.0 77.7 40.3 119.0 455.1 289.0 256.4 198.6 64.0 13.3 6.0 4.6 2.9 4.8 9.1 1,542
1998 0.3 42.0 84.5 70.5 153.4 702.8 199.6 131.7 110.7 27.8 6.1 5.6 2.6 2.5 4.5 1,545
1999 0.2 10.3 298.7 225.0 103.0 157.0 469.7 131.0 56.5 33.2 4.0 2.2 0.9 0.5 2.1 1,494
2000 0.0 16.1 82.4 428.5 346.5 106.7 168.4 357.7 84.9 29.7 22.0 5.2 1.4 0.6 1.0 1,651
2001 0.0 3.2 42.8 154.5 581.0 415.0 137.2 129.0 157.2 57.9 33.6 16.2 5.5 3.1 1.9 1,738
2002 0.8 47.0 108.1 217.8 287.6 606.3 268.0 98.5 85.9 93.9 34.6 14.4 11.0 3.0 1.8 1,879
2003 0.0 14.5 411.8 324.1 360.4 301.5 337.6 158.6 49.4 39.3 35.7 22.9 6.6 3.6 3.2 2,069
2004 0.0 0.5 89.6 831.1 480.6 236.8 169.3 156.3 65.0 16.1 17.1 25.3 9.4 5.9 6.9 2,110
2005 0.0 4.8 52.2 392.9 863.8 484.6 159.5 68.1 66.6 30.1 10.0 9.1 3.2 2.5 3.4 2,151
2006 0.0 9.9 84.2 295.8 619.6 597.6 278.6 107.3 48.0 38.4 17.7 8.2 8.3 5.3 7.2 2,126
2007 1.7 15.7 59.2 139.2 389.4 512.0 300.8 137.1 47.6 27.5 21.9 8.9 6.5 3.4 10.8 1,682
2008 0.0 25.2 58.8 79.2 147.0 309.7 242.3 148.7 84.3 22.2 17.6 14.4 8.6 2.8 12.7 1,173
2009 0.0 1.3 175.5 200.6 82.6 114.4 124.3 104.3 66.6 40.2 23.5 7.6 7.5 2.7 8.7 960
2010 1.1 26.5 31.8 559.4 220.5 54.7 43.0 57.7 51.8 31.8 16.0 8.6 6.0 4.4 5.1 1,118
2011 0.4 10.4 193.3 115.4 809.2 284.7 63.6 37.5 38.5 41.4 25.8 12.5 1.8 4.0 4.3 1,643
2012 0.0 22.3 116.7 946.7 172.8 432.6 141.6 36.7 17.4 14.6 15.9 13.5 7.4 6.1 3.3 1,948
2013 1.8 1.0 64.0 342.4 955.9 194.4 156.5 70.0 20.7 12.8 12.8 10.9 7.8 4.8 5.7 1,861
2014 0.0 39.2 31.0 167.8 399.3 751.8 210.2 86.2 29.8 9.0 4.5 4.5 4.6 2.8 6.0 1,747
2015 0.0 15.5 632.4 196.4 228.6 384.3 510.1 88.8 42.1 17.7 2.9 2.1 3.1 2.7 1.2 2,128
2016 0.0 0.5 90.6 1390.3 159.9 174.5 174.8 224.7 34.1 13.8 8.0 0.5 1.2 0.7 1.0 2,274
2017 0.0 2.2 28.2 549.1 899.0 215.5 147.6 122.1 97.3 21.8 7.2 5.6 0.5 0.2 0.1 2,096
2018 0.0 1.3 13.8 115.0 1216.1 506.6 104.8 82.0 60.6 25.9 4.3 1.1 0.4 0.6 0.5 2,133
2019 0.7 10.9 12.3 18.4 157.6 916.8 422.5 93.2 52.1 53.0 10.1 2.9 0.8 0.0 0.0 1,751
2020 3.5 247.7 85.5 101.1 135.2 551.1 597.8 124.0 52.8 38.6 27.3 6.8 1.8 1.1 0.0 1,974
2021 0.0 111.5 1297.0 144.2 110.1 107.2 309.6 296.0 72.1 26.5 16.2 8.5 2.1 0.0 0.4 2,501
2022 0.0 62.3 174.5 1035.4 183.7 70.4 79.5 141.9 81.1 16.3 11.3 4.1 6.0 1.0 0.0 1,867
2023 0.0 25.2 86.6 263.0 1473.1 227.2 29.4 45.4 63.6 42.6 18.8 5.4 8.6 2.6 0.4 2,292
2024 0.7 2.9 104.8 131.5 362.9 1277.6 113.7 22.3 32.9 22.8 25.3 10.2 3.4 1.9 0.1 2,113
2025 0.0 28.8 50.7 100.3 129.5 526.2 852.1 92.5 29.3 26.0 8.0 19.7 0.0 0.0 6.2 1,869
Table 6:Bycatch estimates (t) of other species caught in the Bering Sea directed pollock fishery, 1991-2026.
Year P.cod Rock.Sole Flathead Arrowtooth POP Yellowfin Sablefish Shark Atka.Mkrl Skates Other
1991 24,310 5,121 NA 5,719 418 418 10 NA 24 NA 10,973
1992 24,005 7,234 3 4,311 173 892 8 NA 261 NA 15,552
1993 20,931 8,714 NA 1,223 283 1,102 2 NA 40 NA 8,127
1994 14,409 3,010 NA 2,011 171 1,208 2 NA 44 NA 4,435
1995 19,777 2,180 2,175 1,177 142 675 12 NA 211 NA 1,897
1996 15,174 2,042 3,208 1,844 303 1,798 7 NA 384 NA 3,718
1997 8,263 1,523 2,350 985 428 606 2 NA 83 NA 3,187
1998 6,255 770 2,048 1,713 617 1,745 2 NA 10 NA 2,449
1999 3,220 1,059 1,885 273 121 350 7 NA 158 NA 1,740
2000 3,433 2,688 2,510 979 21 1,466 12 NA 2 NA 1,859
2001 3,880 1,673 2,199 530 574 594 21 NA 41 NA 3,226
2002 5,887 1,886 1,845 607 543 768 34 NA 221 NA 2,775
2003 5,968 1,419 1,501 618 935 210 48 NA 762 NA 1,992
2004 6,437 2,554 2,104 557 394 841 17 NA 1,053 NA 2,649
2005 7,413 1,125 2,352 651 652 63 11 NA 678 NA 2,759
2006 7,291 1,361 2,862 1,089 736 256 9 NA 789 NA 4,094
2007 5,630 510 4,226 2,795 625 86 12 NA 315 NA 3,731
2008 6,971 2,150 4,315 1,715 336 552 5 NA 15 NA 5,217
2009 7,875 7,591 4,666 2,202 114 271 3 NA 25 NA 4,969
2010 6,908 2,240 4,357 1,454 231 1,057 2 NA 55 NA 2,877
2011 10,043 8,481 4,886 1,602 658 1,083 1 66 900 2,352 1,156
2012 10,066 6,702 3,968 749 706 1,517 1 55 263 2,018 1,483
2013 8,955 6,379 3,146 966 611 2,097 0 43 70 1,750 746
2014 5,242 4,360 2,554 758 1,301 1,954 1 75 117 813 2,526
2015 8,303 1,709 2,260 403 2,525 863 0 52 202 824 2,875
2016 4,980 1,095 1,554 291 3,191 870 18 60 68 423 1,716
2017 6,151 1,708 908 204 4,438 578 96 91 61 448 2,120
2018 4,271 1,077 974 271 3,804 743 396 62 543 508 2,048
2019 6,213 1,117 1,087 422 7,972 444 1,237 101 367 509 790
2020 9,184 866 1,971 688 5,970 1,211 3,453 132 569 827 1,465
2021 9,104 830 1,531 413 2,468 754 1,105 173 545 912 566
2022 3,785 677 948 242 1,445 887 321 55 157 561 357
2023 3,821 549 844 245 1,345 750 487 271 40 400 458
2024 2,923 888 961 332 1,811 523 103 130 45 371 518
2025 3,315 557 1,813 293 3,995 231 51 155 12 438 873
2026 6,549 1,586 3,367 489 2,412 566 125 194 13 823 636

Source: AKFIN / NMFS Alaska Regional Office FMP catch export. Estimates sum retained and discarded catch across both pollock target categories and all reported gears in the BS subarea. Pollock, salmon, halibut, Non TAC Species, and records without a species group are excluded. Other combines remaining named source groups, including other flatfish and rockfish, Greenland turbot, Alaska plaice, squid, octopus, sculpins, and historical Other / Other Species groups; definitions follow the source export rather than a fixed modern FMP list. NA means no records for that category and year, rather than a measured zero. Source group names and the complete column map are available with the annual CSV. Values are summed before rounding; units are metric tons. The 2026 estimates are preliminary through the week ending October 24. Download annual estimates (CSV) · Column definitions (CSV).

Table 7:Pollock bycatch (t) in identified non-pollock directed Bering Sea fisheries, 1991-2026.
Year Rock.sole Other.flats Other.spp P.cod Yellowfin.sole Total
1991 9,711 7,992 756 10,695 NA 29,155
1992 9,825 1,372 568 20,778 13,101 45,644
1993 18,583 2,581 524 31,299 15,253 68,240
1994 15,784 6,770 89 26,594 33,200 82,438
1995 7,766 5,211 58 25,691 27,041 65,768
1996 7,699 5,457 205 22,382 22,255 57,997
1997 9,123 3,480 13 33,658 24,101 70,375
1998 3,960 3,011 61 10,469 15,339 32,840
1999 5,207 4,772 258 21,131 8,701 40,070
2000 5,481 7,068 43 14,509 13,425 40,526
2001 4,578 4,740 488 11,571 16,503 37,879
2002 9,942 2,220 52 15,256 14,490 41,960
2003 4,925 3,672 261 15,926 11,579 36,362
2004 8,976 6,396 194 18,650 10,384 44,600
2005 7,235 5,058 202 14,110 10,313 36,917
2006 6,986 3,826 143 15,168 5,967 32,091
2007 3,245 4,353 276 20,320 4,021 32,215
2008 4,931 4,822 17 9,534 9,828 29,132
2009 6,172 3,505 14 7,876 7,037 24,603
2010 6,074 3,317 86 6,576 5,179 21,232
2011 6,931 2,302 301 8,981 8,674 27,189
2012 6,704 1,751 413 8,377 11,198 28,443
2013 7,327 4,048 238 9,801 20,172 41,586
2014 11,259 6,404 203 11,502 24,713 54,080
2015 9,387 4,994 430 9,062 21,282 45,154
2016 11,850 3,687 450 9,071 22,306 47,365
2017 5,616 3,612 508 8,319 23,414 41,471
2018 5,182 3,525 957 8,008 28,235 45,908
2019 3,176 7,972 1,367 7,594 23,153 43,262
2020 6,401 2,373 728 5,512 31,651 46,666
2021 2,399 5,098 1,415 4,316 24,845 38,073
2022 2,977 5,505 2,627 6,260 26,515 43,884
2023 11,048 4,586 3,076 7,182 22,348 48,239
2024 15,126 4,356 1,929 6,690 18,895 46,996
2025 10,776 2,070 1,279 6,427 8,710 29,263
2026 13,847 7,040 1,345 6,599 5,898 34,729

Source: AKFIN / NMFS Alaska Regional Office FMP catch export, BS subarea. Estimates include retained and discarded pollock catch and all reported gears. Pollock-directed trips, blank trip targets, and No retained catch targets are excluded. Other.flats combines flathead sole, arrowtooth flounder, other flatfish, Alaska plaice, Kamchatka flounder, and Greenland turbot targets. Other.spp combines the remaining identified targets: rockfish, sablefish, Atka mackerel, Other Species, and halibut. Rock.sole is the source Rock Sole - BSAI target; it is not restricted to a separately identified northern rock sole target. NA means no records for that target group and year. Total sums the included unrounded values; displayed columns may differ from Total by rounding. Units are metric tons. The 2026 estimates are preliminary through the week ending October 31. The complete target map and exclusion totals accompany the annual CSV. Download annual estimates (CSV) · Column definitions (CSV).

Table 8:Bycatch estimates of prohibited species in the BSAI directed pollock fishery, 1991–2026.
YearBairdiChinookHalibHalib.MHerringNonChinSnow CrabRed KingBlue KingGolden King
19911,398,10739,0542,156NA3,15928,7094,380,02317,777NANA
19921,500,76533,6722,220NA64740,1874,569,66243,874NANA
19931,649,10336,6191,326NA527241,980738,25958,140NANA
1994371,21431,8909636891,62792,011811,73442,361NANA
1995153,99313,40349239790517,755206,6514,644NANA
199689,41655,4723823211,24277,17463,3985,934NANA
199717,04644,3202572001,13565,415216,152137NANA
199857,07151,24535327880160,677123,75814,287NANA
19997,54911,97815412580045,16920,38692NANA
20001,5174,9611109148358,5686,580NANANA
20015,14633,44424320022557,0045,709106NANA
20022,17234,49516513810980,6412,90820NANA
200377145,6618974967188,3397505290
20041,13951,75196921,096442,1487122742
200563168,126120112594703,0802,260001
20061,34582,653132122434305,7932,79628903
20071,497121,95631229035286,3803,165703
20089,17921,24237333612815,1339,327676833
20096,20412,7315414576545,9607,3921,137200
201012,8469,83533526734913,73410,2911,124350
201110,98625,499460378377193,7546,584577260
20125,62111,3434633882,35322,2976,25034400
201312,42713,091334272959125,5258,70450834107
201412,52215,135239200160219,83719,4553680148
20158,87218,3291521301,487237,8038,339000
20162,29522,2041211031,431343,2081,1664400106
20177,27030,0799789964467,7503,407203067
20182,24913,7267562474295,8185,143565053
20193,14625,0381341131,102348,6316,22845399445
202010,74932,2041281023,861343,62540,0054791522
20218,41713,8521451311,709546,4724,668520115
20224,7586,4151701561,708242,3751,9523115988
202311,99711,87488703,087112,5124,100540132
202410,1208,05481531,28135,15210,55323014
20254,82219,82579663,030151,45714,4241,01812
20263,33615,15364563,354149,4684,35314805

Source: author-provided AKFIN / NMFS Alaska Regional Office export, received from AKR October 27, 2026 and loaded November 7, 2026 (earlier source dates remain in some historical records). Both pollock target categories and all reported gears are included. Herring, halibut catch (Halib), and halibut mortality (Halib.M) are metric tons; other columns are estimated numbers of individuals. Values are summed before rounding. NA denotes unavailable estimates; zero denotes a reported zero. Sums use available values when individual records are missing; halibut mortality is unavailable for 1991–1993 and has some missing records in 1998–2003. The 2026 values are preliminary, through the week ending October 24. Other King Crab is outside the species columns of the example table. Download annual PSC estimates (CSV) · Column definitions (CSV).

Table 9:Estimated catch (t) of selected nontarget-species groups in the BSAI directed pollock fishery, 2003-2026.
Year Jellies MiscFish SeaStar Osmerid Grenadier Eelpouts Sea.pen Anemone Snails Other
2003 5,644 101 89 10 21 7 1 0 1 2
2004 6,590 90 7 22 14 1 1 0 1 1
2005 5,198 158 10 13 14 1 2 0 7 3
2006 2,718 154 11 102 16 21 2 1 0 14
2007 2,403 203 5 140 28 119 4 0 0 13
2008 4,185 121 20 4 28 9 1 1 2 9
2009 8,118 135 10 6 5 4 3 1 1 3
2010 2,518 150 12 1 2 1 3 2 1 10
2011 8,233 277 27 2 2 1 3 2 1 8
2012 3,519 143 7 2 2 1 3 1 1 4
2013 5,294 121 15 1 2 2 2 2 1 10
2014 12,767 45 30 2 10 8 3 2 2 9
2015 4,951 90 42 24 4 11 2 2 1 5
2016 2,203 75 55 5 4 23 1 1 0 4
2017 6,153 48 12 3 3 18 1 1 1 2
2018 8,252 52 25 1 9 4 1 1 0 4
2019 3,889 73 51 1 9 2 1 0 0 6
2020 3,150 94 61 1 43 6 1 6 1 26
2021 7,831 35 20 0 55 1 2 3 1 3
2022 7,609 23 185 1 11 0 1 1 1 11
2023 7,088 38 28 0 86 1 2 3 1 6
2024 4,402 43 16 3 18 3 1 4 0 3
2025 1,769 99 8 4 6 14 2 1 1 3
2026 4,418 68 5 3 1 1 2 0 1 2

Source: AKFIN / NMFS Alaska Regional Office nontarget catch-accounting export. BSAI records (BS and AI) are included; GOA and inside-water records are excluded. Both pollock target categories, all reported gears, and retained and discarded records are combined using Nontarget Estimate (mt), not the species-count field. Squid, sculpins, and seabirds are outside the selected groups of this table and are excluded. MiscFish is the source Misc fish group. Osmerid combines capelin, eulachon, other osmerids, family Osmeridae smelts, and surf smelt; Grenadier combines all named grenadier groups. Other contains the remaining selected fish and invertebrate groups; the complete mapping accompanies the annual CSV. NA means no records for a group-year; a displayed zero may be a positive estimate below 0.5 t. Values are summed before rounding to whole metric tons. The 2026 estimates are preliminary through the week ending October 24. The November 2024 summary approximately doubled the 2019-2022 Jellies, MiscFish, SeaStar, Osmerid, Grenadier, and Eelpouts columns relative to September. Sea pen, Anemone, Snails, and Other changed non-uniformly, with cross-column numerical matches indicating changed alignment or allocation. These are comparisons of historical headers. The current table uses explicit source species names and both catch dispositions, with no scaling adjustment. The upstream preparation step remains unconfirmed. View the jellyfish source-history and filter audit. Download annual estimates (CSV) · Column definitions (CSV).

Table 10: Numbers of EBS pollock measured for fishery length frequencies, by sex and processing stratum, 1977–2025.
Year
A
B southeast
B northwest
Total
Male Female Male Female Male Female
1977 26,411 25,923 4,301 4,511 29,075 31,219 121,440
1978 25,110 31,653 9,829 9,524 46,349 46,072 168,537
1979 59,782 62,512 3,461 3,113 62,298 61,402 252,568
1980 42,726 42,577 3,380 3,464 47,030 49,037 188,214
1981 64,718 57,936 2,401 2,147 53,161 53,570 233,933
1982 74,172 70,073 16,265 14,885 181,606 163,272 520,273
1983 94,118 90,778 16,604 16,826 193,031 174,589 585,946
1984 158,329 161,876 106,654 105,234 243,877 217,362 993,332
1985 119,384 109,230 96,684 97,841 284,850 256,091 964,080
1986 186,505 189,497 135,444 123,413 164,546 131,322 930,727
1987 373,163 399,072 14,170 21,162 24,038 22,117 853,722
1988 NA NA NA NA NA NA NA
1989 NA NA NA NA NA NA NA
1990 NA NA NA NA NA NA NA
1991 155,876 143,625 148,385 132,539 123,516 122,241 826,182
1992 152,566 148,024 150,829 152,003 93,073 94,701 791,196
1993 136,211 126,635 145,280 137,384 24,797 26,057 596,364
1994 138,179 146,067 154,311 148,497 26,431 26,380 639,865
1995 128,719 125,847 175,115 150,323 16,142 16,327 612,473
1996 147,992 139,905 193,493 149,814 18,101 18,288 667,593
1997 123,454 102,619 114,846 106,001 58,492 51,498 556,910
1998 135,136 109,119 205,282 174,676 31,968 39,475 695,656
1999 36,035 32,407 38,229 35,084 16,258 18,321 176,334
2000 64,430 58,030 63,746 41,027 40,839 39,105 307,177
2001 79,190 75,491 54,037 51,179 44,232 45,766 349,895
2002 71,502 69,467 65,299 64,243 37,661 39,285 347,457
2003 74,902 77,533 49,307 52,899 51,764 53,435 359,840
2004 75,208 75,811 63,146 61,957 47,261 44,220 367,603
2005 75,784 68,665 43,271 33,917 68,831 63,022 353,490
2006 72,543 63,349 35,378 27,939 77,620 67,219 344,048
2007 66,533 63,969 38,104 29,558 76,755 70,504 345,423
2008 51,303 46,296 23,467 20,462 64,126 60,678 266,332
2009 43,476 41,540 17,343 16,148 45,418 47,926 211,851
2010 41,019 39,495 20,577 19,194 40,914 40,449 201,648
2011 62,295 58,481 65,057 60,208 48,055 50,927 345,023
2012 57,946 53,557 46,942 45,024 53,243 49,968 306,680
2013 62,148 51,984 44,582 37,307 49,649 49,161 294,831
2014 58,066 55,954 51,743 46,568 46,067 46,642 305,040
2015 56,419 55,646 43,601 46,853 41,183 45,117 288,819
2016 58,915 57,478 69,654 72,973 9,015 10,264 278,299
2017 64,693 55,965 65,982 70,285 14,125 15,871 286,921
2018 64,628 57,156 49,653 56,243 32,796 35,811 296,287
2019 64,665 49,191 54,927 59,416 27,753 34,955 290,907
2020 65,609 60,018 47,791 53,161 48,459 53,985 329,023
2021 75,561 59,580 53,205 61,208 27,641 30,833 308,028
2022 114,918 93,686 86,598 94,900 33,622 36,012 459,736
2023 73,284 54,056 38,537 42,259 38,222 37,101 283,459
2024 72,356 60,933 47,300 53,442 33,511 33,693 301,397
2025 78,854 65,020 39,796 42,845 43,374 48,084 319,026
Table 11: Numbers of EBS pollock with paired fish-weight and length measurements, by sex and processing stratum, 1977–2025.
Year
A
B southeast
B northwest
Total
Male Female Male Female Male Female
1977 1,222 1,338 137 166 1,461 1,664 5,988
1978 1,991 2,686 409 516 2,200 2,623 10,425
1979 2,709 3,151 152 209 1,469 1,566 9,256
1980 1,849 2,156 99 144 612 681 5,541
1981 1,821 2,045 51 52 1,623 1,810 7,402
1982 2,030 2,208 181 176 2,852 3,043 10,490
1983 1,199 1,200 144 122 3,268 3,447 9,380
1984 980 1,046 117 136 1,273 1,378 4,930
1985 520 499 46 55 426 488 2,034
1986 689 794 518 501 286 286 3,074
1987 1,351 1,466 25 33 72 63 3,010
1988 NA NA NA NA NA NA NA
1989 NA NA NA NA NA NA NA
1990 NA NA NA NA NA NA NA
1991 2,893 2,791 1,209 1,116 2,536 2,408 12,953
1992 1,605 1,537 556 600 2,003 1,940 8,241
1993 1,278 1,205 451 437 1,412 1,459 6,242
1994 1,638 1,553 174 166 1,591 1,584 6,706
1995 1,258 1,220 232 223 1,352 1,331 5,616
1996 2,165 2,117 NA NA 1,393 1,421 7,096
1997 629 630 552 536 674 620 3,641
1998 1,958 1,865 357 335 936 982 6,433
1999 4,813 5,337 3,767 3,546 7,182 7,954 32,599
2000 11,346 12,457 7,736 7,991 7,800 12,463 59,793
2001 14,411 14,965 9,064 8,803 10,460 10,871 68,574
2002 13,564 14,098 7,648 7,213 13,004 12,988 68,515
2003 15,535 14,857 10,272 10,031 10,111 9,437 70,243
2004 7,924 7,742 4,318 4,617 6,868 6,850 38,319
2005 7,039 7,428 6,426 6,947 4,114 5,139 37,093
2006 6,566 7,381 6,442 7,406 3,045 4,006 34,846
2007 6,640 6,695 7,081 7,798 3,202 4,305 35,721
2008 4,501 4,865 5,855 6,264 2,236 2,624 26,345
2009 4,033 4,382 4,655 4,511 1,723 1,934 21,238
2010 4,258 4,536 3,883 4,125 2,012 2,261 21,075
2011 5,845 6,388 4,954 4,647 5,929 6,456 34,219
2012 5,494 5,979 4,923 5,346 4,507 4,774 31,023
2013 5,689 6,525 4,844 4,920 3,599 4,313 29,890
2014 5,675 5,871 4,785 4,652 4,753 5,180 30,916
2015 5,310 5,323 4,648 4,194 4,365 4,064 27,904
2016 5,312 5,725 1,077 909 6,872 6,635 26,530
2017 5,238 6,047 1,586 1,343 6,575 6,254 27,043
2018 5,583 6,174 3,430 3,172 5,506 4,850 28,715
2019 4,513 6,086 3,594 2,953 5,809 5,499 28,454
2020 6,116 6,846 5,325 4,815 5,376 4,900 33,378
2021 5,852 7,368 6,247 5,468 2,886 2,698 30,519
2022 4,890 5,847 1,705 1,566 4,899 4,364 23,271
2023 10,676 14,487 6,171 6,173 5,911 5,436 48,854
2024 7,253 6,276 5,027 5,679 3,298 3,421 30,958
2025 7,391 6,333 4,257 4,597 4,379 4,922 31,927
Table 12: Numbers of EBS pollock contributing age estimates, by sex and processing stratum, 1977–2025. The 2024–2025 entries are released FT-NIRS age predictions.
Year
A
B southeast
B northwest
Total
Male Female Male Female Male Female
1977 1,229 1,344 137 166 1,415 1,613 5,904
1978 1,992 2,686 407 514 2,188 2,611 10,398
1979 2,647 3,088 152 209 1,464 1,561 9,121
1980 1,854 2,158 93 138 606 675 5,524
1981 1,819 2,042 51 52 1,620 1,807 7,391
1982 2,030 2,210 181 176 2,865 3,062 10,524
1983 1,200 1,200 144 122 3,249 3,420 9,335
1984 980 1,046 117 136 1,272 1,379 4,930
1985 520 499 46 55 426 488 2,034
1986 689 794 518 501 286 286 3,074
1987 1,351 1,466 25 33 72 63 3,010
1988 NA NA NA NA NA NA NA
1989 NA NA NA NA NA NA NA
1990 NA NA NA NA NA NA NA
1991 439 431 367 349 263 289 2,138
1992 399 396 178 180 391 375 1,919
1993 476 445 122 124 496 507 2,170
1994 201 200 142 132 574 571 1,820
1995 313 299 131 123 420 439 1,725
1996 465 479 NA NA 436 443 1,823
1997 437 434 343 341 313 286 2,154
1998 663 595 237 222 311 316 2,344
1999 506 541 298 308 748 750 3,151
2000 629 667 293 254 596 847 3,286
2001 563 603 205 178 697 736 2,982
2002 672 663 247 202 890 839 3,513
2003 653 588 274 262 701 671 3,149
2004 547 561 221 245 698 600 2,872
2005 599 617 420 422 490 614 3,162
2006 528 609 507 568 367 459 3,038
2007 627 642 552 568 485 594 3,468
2008 513 497 538 650 342 368 2,908
2009 404 484 440 432 240 299 2,299
2010 545 624 413 466 418 505 2,971
2011 581 808 404 396 582 660 3,431
2012 517 571 485 579 480 533 3,165
2013 666 703 525 568 401 518 3,381
2014 609 629 413 407 475 553 3,086
2015 653 642 511 493 508 513 3,320
2016 488 599 157 125 929 969 3,267
2017 604 778 179 163 777 753 3,254
2018 569 662 366 358 621 591 3,167
2019 552 778 387 332 558 531 3,138
2020 757 899 405 420 450 408 3,339
2021 760 910 588 542 270 256 3,326
2022 609 777 209 212 616 563 2,986
2023 452 633 350 313 399 342 2,489
2024 700 616 493 534 291 350 2,985
2025 697 562 401 433 439 456 2,992
Table 13: Pollock sampling effort from the NMFS bottom-trawl survey, 1982–2026 (counts). Historical values are as reported; recent haul counts use the survey records and recent ages are released EBS assignments, including FT-NIRS ages.
Year Hauls Lengths Aged / age assigned
1982 329 40,001 1,611
1983 354 78,033 1,931
1984 355 40,530 1,806
1985 434 48,642 1,913
1986 354 41,101 1,344
1987 356 40,144 1,607
1988 373 40,408 1,173
1989 373 38,926 1,227
1990 371 34,814 1,257
1991 371 43,406 1,083
1992 356 34,024 1,263
1993 375 43,278 1,385
1994 375 38,901 1,141
1995 376 25,673 1,156
1996 375 40,789 1,387
1997 376 35,536 1,193
1998 375 37,673 1,261
1999 373 32,532 1,385
2000 372 41,762 1,545
2001 375 47,335 1,641
2002 375 43,361 1,695
2003 376 46,480 1,638
2004 375 44,102 1,660
2005 373 35,976 1,676
2006 376 39,211 1,573
2007 376 29,679 1,484
2008 375 24,635 1,251
2009 376 24,819 1,342
2010 517 23,142 1,385
2011 376 36,227 1,734
2012 376 35,782 1,785
2013 376 35,908 1,847
2014 376 43,042 2,099
2015 376 54,241 2,320
2016 376 50,857 1,766
2017 519 47,873 1,623
2018 376 48,673 1,486
2019 520 42,382 1,519
2020 NA NA NA
2021 520 53,545 2,050
2022 520 36,687 1,980
2023 492 38,618 1,677
2024 350 36,137 1,526
2025 487 30,862 1,619
2026 350 31,296 1,582
NA denotes an unavailable count; the survey was absent in 2020. The 2025 haul count includes 350 EBS and 137 NBS records; the 2026 count includes 350 EBS records. Historical coverage varies among years.
The 2025 and 2026 length counts use the EBS production summaries. Recent length and age counts cover EBS; haul counts include NBS where stated.
Recent age assignments are distinct from traditional tester-pair counts; historical age counts retain their published definitions.
Table 14: Bottom-trawl survey (BTS) pollock biomass for the combined eastern and northern Bering Sea, 1982–2026, with assessment standard errors (SE) and coefficients of variation (CV).
Year Biomass (million t) SE (thousand t) CV (%)
1982 4.064 732 18.0%
1983 10.457 1,174 11.2%
1984 6.777 977 14.4%
1985 7.794 1,008 12.9%
1986 7.459 1,078 14.5%
1987 8.131 1,399 17.2%
1988 12.000 1,896 15.8%
1989 10.554 1,435 13.6%
1990 11.449 2,352 20.5%
1991 7.472 1,427 19.1%
1992 6.961 1,121 16.1%
1993 8.275 1,060 12.8%
1994 7.385 1,159 15.7%
1995 7.631 2,335 30.6%
1996 4.179 551 13.2%
1997 4.842 890 18.4%
1998 3.665 565 15.4%
1999 5.732 1,020 17.8%
2000 7.778 1,350 17.4%
2001 6.271 705 11.2%
2002 7.117 971 13.6%
2003 12.148 4,671 38.5%
2004 6.063 739 12.2%
2005 6.867 952 13.9%
2006 4.181 513 12.3%
2007 6.511 992 15.2%
2008 4.271 633 14.8%
2009 2.860 482 16.8%
2010 5.174 839 16.2%
2011 4.524 520 11.5%
2012 5.063 681 13.5%
2013 6.739 790 11.7%
2014 11.838 1,266 10.7%
2015 11.145 982 8.8%
2016 8.825 1,006 11.4%
2017 8.781 709 8.1%
2018 5.119 813 15.9%
2019 9.026 967 10.7%
2021 4.706 338 7.2%
2022 6.348 649 10.2%
2023 4.754 429 9.0%
2024 8.354 1,196 14.3%
2025 5.801 792 13.7%
2026 9.034 956 10.6%
CV is the annual standard error divided by biomass. These are the uncertainties used in the assessment, which also accounts for correlations among years. The survey was absent in 2020.
Table 15: Combined eastern and northern Bering Sea model-based pollock abundance at age used for the assessment, 1982–2026 (million fish). Ages 15 and older are pooled as 15+.
Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15+ Total
1982 1220.6 2780.1 3221.8 4394.2 1481.2 196.2 126.3 60.7 37.7 23.7 14.8 8.8 3.3 1.4 1.4 13572.2
1983 4548.2 1080.4 2880.1 4538.0 9238.2 2681.1 458.1 210.7 97.6 87.7 62.5 22.9 8.3 7.7 3.6 25925.1
1984 494.0 404.5 803.7 2218.2 2460.1 5226.9 929.5 201.8 92.6 31.1 21.3 8.0 4.9 6.1 3.1 12905.9
1985 5028.8 787.5 3999.5 1409.8 4629.4 2808.1 1856.2 353.5 86.3 73.3 25.6 8.0 8.6 0.7 0.7 21075.9
1986 3061.3 918.2 793.9 3276.1 1686.3 2542.1 2103.4 1790.2 534.1 83.7 37.4 16.5 1.5 4.6 1.6 16850.8
1987 495.7 706.6 1227.4 956.9 5641.8 1477.3 1356.5 522.5 1628.6 256.8 79.2 30.0 5.9 2.9 2.6 14390.8
1988 1588.1 769.9 2287.4 4488.9 1959.7 6093.4 1659.9 1198.1 666.8 1611.9 155.7 91.5 20.6 24.6 14.8 22631.4
1989 944.5 576.1 979.3 2967.0 6523.0 1245.0 4451.9 628.4 703.5 263.0 825.0 141.4 126.8 59.2 95.4 20529.5
1990 2285.0 272.5 107.0 1089.6 2485.0 8094.0 1492.5 3554.8 337.0 587.7 89.3 832.7 71.8 52.6 73.2 21424.7
1991 3250.4 947.9 368.5 134.1 952.9 836.1 2526.4 881.9 1708.2 430.0 576.7 117.6 346.1 52.7 60.4 13189.9
1992 1617.8 418.5 2737.7 428.0 520.3 836.6 731.6 1010.7 438.8 810.1 281.6 355.1 153.0 121.0 97.3 10558.3
1993 2776.9 444.9 1162.3 5158.9 1074.2 819.5 409.8 538.4 681.7 416.6 359.3 261.2 209.2 115.1 140.3 14568.1
1994 1722.8 695.5 525.9 2019.7 5779.3 950.8 229.2 178.9 196.0 361.9 221.7 308.3 118.8 117.1 198.7 13624.6
1995 1631.4 204.8 456.2 1978.6 2724.3 4580.8 1714.5 388.3 229.3 147.8 272.0 112.0 206.2 84.3 134.9 14865.5
1996 2000.9 437.8 198.4 408.0 1127.1 1494.9 1288.5 423.6 102.1 111.4 74.7 142.5 48.6 87.4 128.8 8074.7
1997 2338.7 398.5 216.5 265.8 3005.0 1397.2 817.3 1038.9 178.6 90.3 66.3 71.4 124.0 40.3 152.6 10201.3
1998 902.8 708.6 371.2 262.0 548.3 3044.7 782.6 476.6 364.3 94.0 41.5 14.1 32.9 35.1 86.7 7765.4
1999 1000.6 1041.4 1090.9 1116.1 634.3 1180.5 2883.0 751.1 362.3 337.0 126.5 54.0 22.4 33.6 123.5 10757.3
2000 1053.0 376.4 703.0 2187.0 2206.2 1225.8 970.7 2977.1 1110.5 573.6 246.2 158.1 50.3 23.0 103.9 13964.7
2001 1985.9 1224.0 712.7 713.1 1687.0 1656.8 688.4 335.0 987.1 704.8 269.8 212.6 82.1 30.2 87.2 11376.7
2002 1319.8 393.9 794.7 1211.9 1379.5 1789.1 892.4 430.4 575.4 1076.3 538.2 249.8 149.1 48.0 57.8 10906.2
2003 565.2 170.1 1149.5 1885.8 2127.9 1800.1 2248.6 1153.8 477.1 626.8 1226.1 562.9 236.1 98.8 109.5 14438.2
2004 401.3 266.2 191.1 1614.3 1597.9 1188.0 665.2 702.3 346.8 219.4 220.1 406.2 181.4 48.1 40.8 8089.1
2005 397.3 153.0 251.1 1214.6 3364.3 2117.6 1068.1 485.3 369.1 269.1 75.0 156.8 261.1 108.4 123.4 10414.1
2006 822.5 76.0 113.3 525.4 1405.2 1644.7 972.2 442.0 245.2 204.2 98.3 61.0 87.9 119.3 123.5 6940.6
2007 2730.3 65.0 224.4 719.4 2148.5 2411.1 1628.2 1147.3 449.4 195.6 180.2 154.0 71.7 88.1 178.4 12391.4
2008 501.3 122.5 141.0 269.9 777.1 1573.6 1152.4 734.2 437.9 158.4 129.9 97.2 44.2 24.6 159.1 6323.3
2009 863.4 210.1 435.1 497.8 325.1 488.6 690.0 521.6 371.6 171.0 107.8 35.1 35.2 18.3 80.1 4850.6
2010 480.0 136.6 315.5 4277.0 1722.7 479.2 379.3 389.4 391.1 268.4 227.6 82.8 49.9 29.5 68.1 9296.8
2011 1331.7 136.3 359.0 431.6 2165.5 1048.1 294.4 160.1 244.1 240.6 205.5 158.0 69.4 33.1 98.2 6975.5
2012 1341.7 211.1 485.1 4164.0 951.6 1431.6 456.1 171.2 115.0 158.5 127.7 110.9 96.5 34.9 67.6 9923.3
2013 1257.5 134.9 273.7 1127.2 5422.6 1228.5 750.4 262.1 88.5 79.4 105.0 79.8 77.2 44.9 63.6 10995.3
2014 2531.9 477.4 279.9 497.3 2312.4 7741.2 3820.1 797.9 435.3 157.6 62.1 89.1 93.0 46.9 141.4 19483.5
2015 1460.1 947.2 2835.6 767.6 1528.6 2738.5 5150.1 1522.0 385.3 192.1 27.0 25.2 49.9 30.5 70.4 17730.0
2016 782.9 507.3 744.5 4155.6 1720.4 1196.9 1767.8 2703.3 547.2 224.0 79.7 17.8 18.7 6.8 14.1 14486.9
2017 789.3 312.7 526.1 2619.5 3497.6 1602.5 1236.2 1161.9 1488.5 425.9 163.7 55.1 8.4 4.8 16.2 13908.4
2018 1179.6 474.1 251.5 376.6 2531.9 1556.8 541.1 393.9 405.0 333.0 93.2 14.6 1.9 0.3 5.8 8159.1
2019 2685.3 712.4 584.7 619.6 1763.6 6308.4 2520.5 597.1 431.0 254.9 133.9 60.8 24.1 6.9 2.7 16705.9
2020 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
2021 1027.6 827.5 1953.4 765.3 703.6 508.1 1291.4 1479.8 391.6 152.5 127.5 82.6 18.2 12.9 4.4 9346.2
2022 821.4 348.4 595.5 4025.4 1888.9 733.5 815.5 1143.0 855.9 271.4 116.2 96.7 37.6 21.3 2.2 11773.0
2023 1152.8 388.7 341.0 630.2 2710.5 804.7 436.7 424.2 702.6 503.9 126.4 68.4 38.1 11.7 10.6 8350.8
2024 1683.9 957.6 893.4 610.1 1944.1 6404.9 1426.1 447.7 424.6 389.1 275.1 107.7 33.5 14.6 5.4 15617.7
2025 1534.2 344.2 318.5 504.0 491.9 1366.7 3303.4 827.7 327.6 208.0 299.8 162.0 81.4 50.4 26.5 9846.2
2026 3466.8 608.7 1637.4 948.4 1034.1 1390.7 2587.6 2390.8 738.5 253.8 442.7 369.9 114.1 11.4 69.8 16064.7
Mean 1615.3 549.5 921.3 1692.5 2315.4 2225.9 1444.8 863.9 495.2 321.1 205.4 142.5 80.1 41.2 69.3 12983.4
The full current revised series is shown; historical values differ from the earlier published VAST series. Northern survey coverage varies among years. These survey-expansion estimates are distinct from model population numbers at age.
The 2025 and 2026 FT-NIRS products use their year-specific traditional-age keys; the 2026 key retains 307 pairs after excluding 22 flagged pairs. Exact traditional ages 1–18 are converted before 15+ pooling, conserving total abundance. Empirical-key uncertainty is excluded. NA in 2020 denotes no survey observation; the mean uses the 44 observed-year estimates. Values are rounded to 0.1 million fish.
Table 16: Annual BTS-derived population weight-at-age inputs used in Model 26.0, 1982–2026 (kg per fish). Ages 15 and older are pooled as 15+.
Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15+
1982 0.027 0.076 0.180 0.369 0.550 0.862 1.151 1.326 1.463 1.648 1.790 1.778 2.142 1.770 2.633
1983 0.017 0.091 0.179 0.341 0.491 0.691 0.988 1.304 1.494 1.539 1.634 1.600 1.807 1.555 1.961
1984 0.017 0.062 0.187 0.293 0.465 0.605 0.955 1.375 1.520 1.710 1.957 1.829 1.880 1.675 2.091
1985 0.017 0.070 0.183 0.333 0.485 0.753 0.941 1.238 1.667 1.648 1.779 2.062 2.135 1.817 2.505
1986 0.014 0.066 0.137 0.356 0.433 0.657 0.829 1.025 1.270 1.635 1.714 1.952 2.051 2.212 * 2.191
1987 0.028 0.105 0.239 0.291 0.424 0.555 0.705 0.861 0.993 1.224 1.506 1.539 1.931 2.215 2.339
1988 0.019 0.079 0.246 0.331 0.444 0.527 0.661 0.883 0.910 1.101 1.366 1.390 1.872 1.169 1.715
1989 0.022 0.085 0.166 0.293 0.384 0.509 0.710 0.802 1.088 1.072 1.201 1.268 1.303 1.290 1.400
1990 0.019 0.101 0.145 0.337 0.441 0.536 0.633 0.741 0.916 1.134 1.256 1.313 1.393 1.498 1.692
1991 0.025 0.109 0.202 0.339 0.549 0.629 0.714 0.809 0.986 1.108 1.364 1.400 1.552 1.824 1.930
1992 0.018 0.096 0.270 0.381 0.510 0.575 0.774 0.916 0.969 1.083 1.262 1.455 1.601 1.662 1.630
1993 0.015 0.087 0.271 0.470 0.524 0.646 0.757 0.895 1.101 1.112 1.318 1.406 1.561 1.673 1.786
1994 0.019 0.083 0.209 0.388 0.559 0.675 0.719 1.053 1.239 1.199 1.322 1.413 1.525 1.680 1.758
1995 0.016 0.057 0.139 0.339 0.485 0.657 0.693 0.912 1.079 1.328 1.314 1.373 1.501 1.481 1.747
1996 0.021 0.077 0.137 0.297 0.500 0.632 0.797 0.903 1.043 1.176 1.386 1.511 1.680 1.682 1.789
1997 0.018 0.078 0.193 0.299 0.380 0.623 0.754 0.899 1.122 1.185 1.319 1.529 1.583 1.645 1.764
1998 0.018 0.070 0.185 0.323 0.460 0.524 0.801 0.895 1.012 1.082 1.286 1.349 1.485 1.886 1.886
1999 0.016 0.078 0.219 0.347 0.407 0.561 0.700 0.897 1.087 1.152 1.292 1.323 1.754 1.756 1.982
2000 0.014 0.079 0.236 0.400 0.477 0.562 0.704 0.786 0.946 1.164 1.364 1.476 1.720 1.752 2.001
2001 0.018 0.078 0.172 0.359 0.530 0.669 0.797 0.881 0.996 1.118 1.337 1.499 1.589 1.794 1.880
2002 0.017 0.094 0.244 0.389 0.521 0.674 0.760 0.935 1.033 1.121 1.127 1.401 1.563 1.741 1.934
2003 0.027 0.113 0.279 0.461 0.621 0.735 0.815 0.968 1.045 1.201 1.250 1.371 1.548 1.550 1.744
2004 0.023 0.107 0.275 0.421 0.567 0.689 0.819 0.928 1.041 1.152 1.210 1.304 1.456 1.748 1.746
2005 0.022 0.088 0.217 0.395 0.510 0.630 0.809 0.942 1.020 1.108 1.361 1.314 1.299 1.480 1.599
2006 0.011 0.087 0.170 0.421 0.598 0.696 0.815 0.894 1.042 1.164 1.275 1.390 1.467 1.434 1.489
2007 0.014 0.102 0.263 0.497 0.637 0.802 0.907 1.039 1.146 1.406 1.372 1.411 1.723 1.636 1.689
2008 0.014 0.056 0.221 0.455 0.585 0.717 0.846 0.997 1.058 1.237 1.537 1.509 1.726 1.850 1.894
2009 0.012 0.074 0.224 0.499 0.675 0.791 0.999 1.135 1.174 1.481 1.568 1.759 2.049 2.277 2.360
2010 0.020 0.077 0.249 0.510 0.675 0.875 1.094 1.188 1.245 1.352 1.453 1.651 1.876 2.213 2.443
2011 0.017 0.085 0.209 0.499 0.663 0.773 0.938 1.118 1.247 1.296 1.455 1.530 1.638 1.727 2.015
2012 0.015 0.075 0.195 0.420 0.606 0.784 0.933 1.137 1.333 1.401 1.432 1.529 1.558 1.845 2.015
2013 0.018 0.079 0.213 0.501 0.582 0.744 0.993 1.166 1.354 1.409 1.542 1.582 1.710 1.860 1.923
2014 0.019 0.109 0.257 0.438 0.571 0.716 0.791 1.106 1.231 1.423 1.676 1.606 1.672 1.847 1.903
2015 0.020 0.090 0.327 0.445 0.588 0.686 0.784 0.905 1.166 1.229 1.496 1.550 1.432 1.492 1.750
2016 0.023 0.080 0.279 0.531 0.595 0.697 0.779 0.828 0.904 1.004 1.137 1.554 1.351 1.536 1.421
2017 0.021 0.092 0.231 0.472 0.625 0.673 0.755 0.814 0.892 0.919 1.057 0.993 1.289 1.123 1.485
2018 0.023 0.092 0.215 0.421 0.591 0.684 0.777 0.816 0.896 0.933 1.036 0.944 1.410 * 1.720 1.540
2019 0.022 0.105 0.286 0.487 0.634 0.731 0.822 0.925 0.937 1.035 0.965 1.066 1.038 1.063 * 1.910
2020 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
2021 0.022 0.101 0.245 0.442 0.585 0.713 0.803 0.857 0.977 1.118 1.040 1.117 1.298 0.999 1.361
2022 0.018 0.112 0.270 0.447 0.590 0.697 0.771 0.873 0.969 1.034 1.254 1.251 1.324 1.205 1.812
2023 0.015 0.106 0.283 0.416 0.536 0.657 0.812 0.955 0.968 1.013 1.179 1.200 1.414 1.759 1.487
2024 0.017 0.090 0.309 0.454 0.560 0.607 0.693 0.923 0.997 1.020 1.126 1.137 1.259 1.406 1.754
2025 0.020 0.079 0.226 0.526 0.587 0.676 0.734 0.812 0.903 1.087 1.066 1.150 1.258 1.399 1.547
2026 0.020 0.066 0.397 0.544 0.640 0.725 0.809 0.874 0.949 1.027 1.048 1.192 1.416 1.449 1.360
Mean 0.019 0.086 0.227 0.409 0.542 0.673 0.815 0.967 1.101 1.218 1.351 1.431 1.587 1.645 1.838
* The selected value is retained. Its current treatment has not been reconciled with an older preparation record identifying these historical cells for filling; the technical supplement preserves that provenance qualification.
The table reproduces the selected schedules, including historical revisions, rather than labeling every cell as an unmodified survey measurement. NA in 2020 marks absence of a survey observation; the model retains its separate annual schedule. The mean uses the 44 displayed annual schedules. Values are rounded to 0.001 kg.
Table 17: Sampling effort and biological collections from eastern Bering Sea acoustic-trawl surveys, 1979–2026 (counts). E and W denote collections east and west of 170°W within the US EEZ; US is the reported US subtotal and RU is the Russian-region count. The 2024 US aged-fish count is 2,260 (McCarthy et al. 2026, p. 15).
Year
Hauls
Length records
Otoliths
Number aged
E W US RU E W US RU E W US RU E W US RU
1979 NA NA 25 NA NA NA 7722 NA NA NA 0 NA NA NA 2610 NA
1982 13 31 48 NA 1725 6689 8687 NA 840 2324 3164 NA 783 1958 2741 NA
1985 NA NA 73 NA NA NA 19872 NA NA NA 2739 NA NA NA 2739 NA
1988 NA NA 25 NA NA NA 6619 NA NA NA 1471 NA NA NA 1471 NA
1991 NA NA 62 NA NA NA 16343 NA NA NA 2062 NA NA NA 1663 NA
1994 25 51 76 19 4553 21011 25564 8930 1560 3694 4966 1270 612 932 1770 455
1996 15 42 57 NA 3551 13273 16824 NA 669 1280 1949 NA 815 1111 1926 NA
1997 25 61 86 NA 6493 23043 29536 NA 966 2669 3635 NA 936 1349 2285 NA
1999 41 77 118 NA 13841 28521 42362 NA 1945 3001 4946 NA 946 1500 2446 NA
2000 29 95 124 NA 7721 36008 43729 NA 850 2609 3459 NA 850 1403 2253 NA
2002 47 79 126 NA 14601 25633 40234 NA 1424 1883 3307 NA 1000 1200 2200 NA
2004 33 57 90 15 8896 18262 27158 5893 1167 2002 3169 461 798 1192 2351 461
2006 27 56 83 NA 4939 19326 24265 NA 822 1871 2693 NA 822 1870 2692 NA
2007 23 46 69 4 5492 14863 20355 1407 871 1961 2832 319 823 1737 2560 315
2008 9 53 62 6 2394 15354 17748 1754 341 1698 2039 177 338 1381 1719 176
2009 13 33 46 3 1576 9257 10833 282 308 1210 1518 54 306 1205 1511 54
2010 11 48 59 9 2432 20263 22695 3502 653 1868 2521 381 652 1598 2250 379
2012 17 60 77 14 4422 23929 28351 5620 650 2045 2695 418 646 1483 2129 416
2014 52 87 139 3 28857 8645 37502 747 1739 849 2588 72 845 1735 2580 72
2016 37 71 108 NA 10912 24134 35046 NA 880 1514 2394 NA 876 1513 2388 NA
2018 36 64 100 NA 11031 21173 32204 NA 1105 1750 2855 NA 1100 1743 2843 NA
2020 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
2022 26 36 62 NA 4954 11994 16948 NA 671 1691 2362 NA 668 1688 2356 NA
2024 14 41 55 NA 4535 14472 19007 NA 725 1561 2286 NA NA NA 2260 NA
2026 36 62 99 NA 11916 23031 35128 NA 1051 1571 2642 NA NA NA NA NA
Table 18: Midwater pollock biomass by area from summer ATS surveys of the U.S. EEZ Bering Sea shelf, 1994–2026 (million tons; near surface to 0.5 m above the seafloor). The core shelf excludes the Northern Extension. Assessment CVs average 20%, with 45% assigned to 2000; SE equals biomass × CV. The 2020 survey used uncrewed sailing vessels; 2026 estimates are preliminary.
Year Date Area (nmi2)
Biomass (million t)
Rel. error Assessment CV Assessment SE (kt)
SCA E170–SCA W170 0.5 m total
1994 9 Jul - 7 Sept 78,251 0.382 0.652 2.594 3.628 0.040 17.0% 618.4
1996 20 Jul - 30 Aug 93,810 0.275 0.492 2.185 2.952 0.032 13.6% 402.5
1997 17 Jul - 5 Sept 102,770 0.272 0.703 2.470 3.446 0.029 12.4% 425.8
1999 12 Jun - 29 Jul 103,670 0.383 0.757 3.060 4.200 0.044 18.8% 787.5
2000 12 Jun - 1 Aug 106,140 0.458 0.715 2.441 3.615 0.028 45.0% 1,626.6
2002 9 Jun - 21 Jul 99,526 0.762 0.938 2.601 4.301 0.027 11.5% 494.9
2004 4 Jun -29 Jul 99,659 0.550 0.918 2.528 3.996 0.031 13.2% 527.9
2006 3 Jun -25 Jul 89,550 0.147 0.340 1.387 1.874 0.033 14.1% 263.6
2007 2 Jun -30 Jul 92,944 0.136 0.245 1.902 2.283 0.038 16.2% 369.7
2008 2 Jun -31 Jul 95,374 0.122 0.087 1.196 1.404 0.056 23.9% 335.2
2009 9 Jun -7 Aug 91,414 0.156 0.058 1.117 1.331 0.069 29.4% 391.5
2010 5 Jun -7 Aug 92,849 0.098 0.193 2.345 2.636 0.054 23.0% 606.6
2012 7 Jun -10 Aug 96,852 0.196 0.319 1.764 2.279 0.034 14.5% 330.3
2014 12 Jun -13 Aug 94,361 0.571 1.458 2.714 4.743 0.034 14.5% 687.2
2016 12 Jun -17 Aug 100,674 0.542 1.268 3.028 4.838 0.019 8.1% 391.7
2018 12 Jun -22 Aug 92,283 0.234 0.510 1.753 2.497 0.039 16.6% 415.1
2020 4 Jul - 20 Aug 102,320 0.398 0.531 2.688 3.617 0.096 40.9% 1,479.8
2022 1 Jun -5 Aug 103,942 0.538 0.823 2.473 3.834 0.068 29.0% 1,111.1
2024 5 Jun - 22 Jul 100,365 0.497 0.593 1.785 2.875 0.056 23.9% 686.1
2026 28 May - 12 Aug 95,091 0.239 0.706 2.738 3.682 0.034 14.5% 533.6
Table 19: Biomass and abundance summed across the 2026 survey intervals, including the below-3 m analysis and northern extension. The three core-shelf regions sum to the historical EBS estimate; the Northern Extension is additional.
Region EDSU records Biomass (t) Abundance (million fish)
SCA 1,079 238,999.6 720.50
East of 170 3,232 705,748.5 1,396.55
West of 170 5,137 2,737,718.7 10,545.58
EBS Northern Extension 1,476 78,311.1 104.29
Table 20: ATS estimates of EBS pollock abundance at age, 1979–2026 (million fish). Ages 10 and older are pooled as 10+. The 2026 estimates use the BTS age–length key applied to ATS length distributions and remain provisional; ages from the 2026 ATS samples are expected in 2027. Mean and median summarize surveys with age compositions during 1994–2026; 1979–1991 provides historical context.
Year
Age
Age 2+ Total at age
1 2 3 4 5 6 7 8 9 10+
1979 69,110 41,132 3,884 413 534 128 30 4 28 161 46,314 115,424
1982 108 3,401 4,108 7,637 1,790 283 141 178 90 177 17,805 17,913
1985 2,076 929 8,149 898 2,186 1,510 1,127 130 21 15 14,965 17,041
1988 11 1,112 3,586 3,864 739 1,882 403 151 130 414 12,280 12,292
1991 639 5,942 967 215 224 133 120 39 37 53 7,730 8,369
1994 1,140 4,969 1,424 1,819 2,252 389 109 96 56 221 11,335 12,475
1996 1,800 567 552 2,741 915 634 585 142 39 165 6,338 8,139
1997 13,227 2,881 440 536 2,330 546 313 290 75 220 7,633 20,860
1999 607 1,780 3,717 1,810 652 398 1,548 526 180 249 10,859 11,466
2000 460 1,322 1,230 2,588 1,012 327 308 950 278 252 8,266 8,726
2002 796 4,944 3,385 1,295 661 935 538 140 162 493 12,554 13,351
2004 83 313 1,217 3,123 1,634 567 288 283 121 265 7,811 7,894
2006 525 217 291 654 783 659 390 145 75 171 3,386 3,910
2007 5,775 1,041 345 478 794 729 407 241 98 135 4,267 10,042
2008 71 2,915 1,047 166 161 288 235 136 102 120 5,169 5,240
2009 5,197 816 1,734 281 77 94 129 111 77 114 3,433 8,630
2010 2,568 6,404 984 2,295 446 73 33 37 38 91 10,400 12,968
2012 177 1,989 1,693 2,710 280 367 113 36 25 103 7,315 7,492
2014 4,751 8,655 969 1,161 1,119 1,770 740 170 79 99 14,762 19,513
2016 174 1,038 4,496 4,476 715 348 392 420 96 64 12,046 12,220
2018 450 517 249 621 2,268 944 198 112 107 104 5,120 5,570
2022 142 332 975 6,578 819 211 133 239 166 79 9,533 9,674
2024 5,075 1,146 681 379 820 2,485 450 110 86 127 6,284 11,359
2026 2,026 3,729 3,958 375 319 403 714 656 198 285 10,637 12,663
Mean 1994–2026 2,371 2,399 1,547 1,794 950 640 401 255 108 177 8,271 10,642
Median 1994–2026 796 1,322 1,047 1,295 794 403 313 145 96 135 7,811 10,042
Table 21: Recent core-area ATS pollock biomass and abundance estimates. The 2026 estimates are preliminary.
Recent core-area ATS estimates
Survey year Biomass (million t) Abundance (billion fish)
2022 3.8 9.67
2024 2.87 11.4
2026 (preliminary) 3.68 12.7
Table 22: Provisional core-area 2026 ATS abundance by age, in million fish, restricted to supported lengths. FT-NIRS source age 15 retains its released label; the corresponding TMA row pools target ages 15–18. The upper-length tail remains unallocated.
Age (FT-NIRS / TMA) FT-NIRS abundance TMA abundance
1 2,194.690 2,025.867
2 5,340.635 3,729.246
3 1,978.834 3,958.120
4 597.222 374.975
5 338.742 318.742
6 299.224 403.011
7 619.494 713.961
8 786.844 656.327
9 343.438 197.732
10 99.819 63.788
11 45.953 106.936
12 12.907 80.216
13 2.903 19.546
14 0.836 1.844
15 / 15+ 0.980 12.210
Table 23: Provisional core-area 2026 ATS TMA biomass, abundance and mean weight-at-age over supported lengths. The 15+ row sums exact ages 15–18 before dividing biomass by abundance. Unsupported upper-length biomass and fish are excluded from these age-specific estimates and retained separately.
TMA age Biomass (t) Abundance (million fish) Mean weight (kg/fish)
1 89,550.280 2,025.867 0.0442
2 525,587.105 3,729.246 0.1409
3 949,648.466 3,958.120 0.2399
4 182,528.304 374.975 0.4868
5 185,878.529 318.742 0.5832
6 263,257.538 403.011 0.6532
7 525,152.651 713.961 0.7355
8 518,643.709 656.327 0.7902
9 168,006.366 197.732 0.8497
10 57,043.013 63.788 0.8943
11 96,454.798 106.936 0.9020
12 81,491.146 80.216 1.0159
13 22,896.782 19.546 1.1714
14 2,181.579 1.844 1.1832
15+ 13,821.450 12.210 1.1320
Table 24: Assumed age-composition likelihood sample sizes used in the completed full-data Model 23.0 fit, 1964–2026. Fishery inputs for 2023–2025 are the applied rounded values 443, 578 and 530; other values are rounded for display.
Year Fishery BTS ATS
1964–1977 10

1978 39

1979 39

1980 39

1981 39

1982 39 153
1983 39 134
1984 39 61
1985 39 76
1986 39 153
1987 39 60
1988 39 81
1989 39 55
1990 39 48
1991 260 79
1992 228 86
1993 344 92
1994 286 91 43
1995 257 103
1996 189 227 32
1997 319 77 49
1998 355 64
1999 476 97 67
2000 482 88 70
2001 328 178
2002 487 187 72
2003 441 130
2004 391 195 51
2005 494 188
2006 506 321 47
2007 500 184 39
2008 524 238 35
2009 420 148 26
2010 549 107 34
2011 728 172
2012 607 108 44
2013 753 64
2014 606 117 79
2015 821 104
2016 704 124 61
2017 607 241
2018 668 156 50
2019 701 120
2020 565
1
2021 818 150
2022 641 181 52
2023 443 135
2024 578 63 79
2025 530 111
2026
131 94
Mean 503 129 51
Table 25: Revised mean-one AVO display index for 17 observations during 2009–2026, excluding 2020, including newly processed 2011 and 2013 values. Sampling relative errors, standard errors and scaled source 95% confidence intervals are retained. The blank 2020 row preserves calendar-year coverage.
Year Index (million m2) Relative error (%) SE (million m2) Relative index SE (relative) 95% CI (relative)
2009 0.6951 12.22% 0.0849 0.2990 0.0365 0.2274–0.3707
2010 1.9218 6.56% 0.1261 0.8268 0.0542 0.7205–0.9331
2011 1.5679 4.51% 0.0707 0.6745 0.0304 0.6149–0.7342
2012 1.5206 5.32% 0.0810 0.6542 0.0348 0.5859–0.7225
2013 2.2347 4.64% 0.1037 0.9614 0.0446 0.8740–1.0488
2014 3.0769 4.11% 0.1263 1.3238 0.0543 1.2172–1.4303
2015 3.5927 2.46% 0.0884 1.5457 0.0380 1.4711–1.6202
2016 2.8319 2.91% 0.0825 1.2184 0.0355 1.1488–1.2879
2017 2.2630 3.05% 0.0691 0.9736 0.0297 0.9153–1.0319
2018 2.0841 2.66% 0.0555 0.8966 0.0239 0.8498–0.9434
2019 2.8292 4.89% 0.1383 1.2172 0.0595 1.1006–1.3338
2020





2021 2.4101 4.79% 0.1154 1.0369 0.0496 0.9396–1.1342
2022 2.9031 3.41% 0.0990 1.2490 0.0426 1.1655–1.3325
2023 2.4810 2.94% 0.0730 1.0674 0.0314 1.0058–1.1289
2024 2.0070 2.72% 0.0546 0.8635 0.0235 0.8174–0.9095
2025 2.4954 5.26% 0.1313 1.0736 0.0565 0.9628–1.1843
2026 2.5997 4.55% 0.1182 1.1185 0.0508 1.0188–1.2181
Source: NOAA AFSC MACE AVO workbook, 2009–2026. The 2020 observation is unavailable, so its data cells are blank.
SE = index × CV. Relative index and SE share the mean-1 scaling; relative error is unchanged. Source 95% intervals are scaled by the same constant.
Table 26: Counts of AVO sampling intervals during 2009–2026, including positive intervals and zeros; these counts describe survey coverage. There are no AVO observations in 2020.
Year Survey intervals Positive intervals Zeros
2009 5,557 2,430 56.3%
2010 5,699 2,584 54.7%
2011 7,829 5,171 34.0%
2012 6,740 4,750 29.5%
2013 8,021 4,725 41.1%
2014 10,032 8,315 17.1%
2015 10,524 9,700 7.8%
2016 8,603 7,912 8.0%
2017 8,798 6,833 22.3%
2018 8,880 8,044 9.4%
2019 8,836 7,301 17.4%
2020 — — —
2021 6,939 6,038 13.0%
2022 9,350 8,502 9.1%
2023 8,740 7,435 14.9%
2024 12,229 10,406 14.9%
2025 7,320 6,952 5.0%
2026 8,699 7,462 14.2%
Table 27: ATS biomass (million tons) and AVO backscatter (million m²), 2006–2026. AVO indices and sampling relative errors for 2009–2026 match Table 25. Assessment CVs from the saved Model 26.0 inputs average 23% across 20 observations; SE equals index × CV. The 2020 USV survey provides ATS biomass; AVO has no observation that year.
Year ATS biomass (million t) AVO index (million m2) Sampling RE Assessment CV Assessment SE (million m2)
2006 1.8741 1.7415 0.0510 27.64% 0.4814
2007 2.2827 2.0019 0.0865 53.90% 1.0790
2008 1.4045 0.9915 0.0643 19.84% 0.1968
2009 1.3314 0.6951 0.1222 56.89% 0.3955
2010 2.6357 1.9218 0.0656 30.55% 0.5872
2011 — 1.5679 0.0451 21.01% 0.3294
2012 2.2794 1.5206 0.0532 24.80% 0.3771
2013 — 2.2347 0.0464 21.60% 0.4827
2014 4.7428 3.0769 0.0411 19.12% 0.5882
2015 — 3.5927 0.0246 11.46% 0.4118
2016 4.8377 2.8319 0.0291 13.57% 0.3843
2017 — 2.2630 0.0305 14.22% 0.3218
2018 2.4973 2.0841 0.0266 12.40% 0.2585
2019 — 2.8292 0.0489 22.77% 0.6441
2020 3.6170 — — — —
2021 — 2.4101 0.0479 22.29% 0.5372
2022 3.8340 2.9031 0.0341 15.88% 0.4610
2023 — 2.4810 0.0294 13.70% 0.3400
2024 2.8750 2.0070 0.0272 12.67% 0.2543
2025 — 2.4954 0.0526 24.51% 0.6117
2026 3.6825 2.5997 0.0455 21.17% 0.5504
Mean 2.9149 2.2125 0.0486 23.00% 0.4646
Table 28: Annual fishery mean weight-at-age (kg), with observational inputs through 2025 and standalone WtAgeRE predictions and forecasts for 2026–2028. Observational inputs extend through 2025; the 2026 row is predicted. Age 15 is a 15+ group. The fixed early schedule and mean/CV definitions are described below.
Year / basis
Age (years)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15+
1964–1990 0.007 0.170 0.303 0.447 0.589 0.722 0.840 0.942 1.029 1.102 1.163 1.212 1.253 1.286 1.312
1991 0.007 0.150 0.285 0.483 0.604 0.730 0.844 0.882 1.020 1.123 1.135 1.237 1.236 1.296 1.247
1992 0.007 0.179 0.397 0.465 0.651 0.714 0.819 0.986 1.030 1.200 1.237 1.269 1.193 1.357 1.431
1993 0.007 0.331 0.495 0.612 0.652 0.775 0.934 1.062 1.198 1.240 1.423 1.540 1.576 1.609 1.508
1994 0.007 0.233 0.400 0.652 0.732 0.746 0.727 1.070 1.380 1.325 1.335 1.409 1.397 1.278 1.370
1995 0.007 0.153 0.386 0.505 0.729 0.843 0.847 0.970 1.232 1.296 1.401 1.402 1.392 1.095 1.306
1996 0.007 0.293 0.336 0.445 0.684 0.797 0.948 0.956 1.025 1.100 1.418 1.489 1.521 1.702 1.602
1997 0.007 0.187 0.327 0.477 0.559 0.748 0.889 1.074 1.095 1.236 1.287 1.400 1.561 1.363 1.338
1998 0.007 0.191 0.369 0.589 0.618 0.622 0.780 1.040 1.169 1.276 1.316 1.428 1.448 1.437 1.528
1999 0.007 0.188 0.404 0.507 0.643 0.702 0.729 0.894 1.038 1.253 1.224 1.422 0.995 0.616 1.239
2000 0.007 0.218 0.353 0.526 0.630 0.732 0.780 0.807 0.968 1.015 1.253 1.286 1.108 1.084 1.359
2001 0.006 0.227 0.329 0.505 0.668 0.786 0.964 0.986 1.061 1.133 1.320 1.411 1.568 1.472 1.495
2002 0.007 0.231 0.385 0.510 0.667 0.799 0.911 1.026 1.113 1.102 1.284 1.442 1.579 1.290 1.568
2003 0.006 0.276 0.489 0.549 0.652 0.769 0.863 0.953 1.086 1.202 1.212 1.194 1.374 1.355 1.709
2004 0.007 0.135 0.408 0.584 0.641 0.760 0.888 0.924 1.036 1.176 1.127 1.167 1.309 1.254 1.185
2005 0.007 0.283 0.351 0.508 0.641 0.742 0.880 0.960 1.062 1.074 1.216 1.268 1.217 1.076 1.342
2006 0.007 0.174 0.306 0.448 0.606 0.755 0.858 0.959 1.060 1.117 1.190 1.218 1.280 1.384 1.417
2007 0.007 0.155 0.349 0.507 0.642 0.783 0.961 1.100 1.192 1.266 1.327 1.488 1.444 1.729 1.512
2008 0.007 0.208 0.328 0.519 0.653 0.774 0.900 1.054 1.117 1.289 1.452 1.528 1.560 1.874 1.645
2009 0.007 0.136 0.340 0.525 0.705 0.879 0.999 1.130 1.398 1.479 1.558 1.576 1.807 2.026 2.222
2010 0.050 0.175 0.381 0.490 0.668 0.909 1.114 1.277 1.374 1.586 1.679 1.923 1.948 2.077 2.271
2011 0.031 0.205 0.290 0.508 0.666 0.809 0.971 1.224 1.342 1.513 1.582 1.623 2.080 1.707 2.242
2012 0.029 0.142 0.271 0.409 0.643 0.824 0.974 1.170 1.303 1.509 1.599 1.637 1.680 2.031 2.062
2013 0.095 0.144 0.290 0.442 0.564 0.781 1.130 1.281 1.440 1.685 1.827 1.786 1.934 2.159 2.182
2014 0.014 0.193 0.319 0.454 0.617 0.751 0.894 1.156 1.307 1.386 1.669 1.773 1.704 1.623 2.215
2015 0.025 0.181 0.404 0.462 0.571 0.690 0.786 0.887 1.141 1.195 1.315 1.671 1.389 1.559 2.600
2016 0.025 0.181 0.409 0.531 0.557 0.646 0.732 0.800 0.941 1.043 1.178 0.788 0.911 1.684 1.429
2017 0.025 0.191 0.408 0.499 0.650 0.694 0.752 0.827 0.894 0.911 1.028 0.961 0.312 0.701 0.688
2018 0.025 0.186 0.377 0.467 0.573 0.734 0.809 0.853 0.906 1.039 0.936 1.110 0.568 0.435 1.130
2019 0.025 0.186 0.422 0.565 0.643 0.759 0.878 0.962 1.007 1.065 1.035 1.182 0.754 0.698 0.769
2020 0.025 0.186 0.387 0.522 0.632 0.716 0.799 0.955 1.006 1.040 1.189 1.072 1.208 0.961 0.769
2021 0.025 0.186 0.393 0.480 0.574 0.690 0.757 0.841 1.011 1.130 1.160 1.269 1.215 0.936 0.408
2022 0.025 0.186 0.440 0.506 0.574 0.724 0.837 0.883 0.984 0.972 1.271 1.044 1.235 0.910 0.770
2023 0.025 0.186 0.494 0.483 0.524 0.602 0.812 0.923 0.957 1.041 1.095 1.294 1.331 1.218 1.131
2024 0.025 0.186 0.435 0.481 0.560 0.617 0.696 0.825 1.016 1.017 1.078 1.251 1.308 1.328 1.559
2025 0.025 0.186 0.314 0.556 0.621 0.693 0.730 0.855 0.966 1.140 1.194 1.082 1.314 1.343 1.268
2026 predicted 0.025 0.186 0.368 0.440 0.677 0.734 0.813 0.864 0.953 1.075 1.194 1.232 1.307 1.420 1.448
2027 forecast

0.368 0.482 0.560 0.800 0.858 0.936 0.985 1.069 1.187 1.300 1.333 1.402 1.508
2028 forecast

0.368 0.482 0.601 0.683 0.924 0.980 1.056 1.101 1.181 1.293 1.400 1.427 1.491
Mean 0.018 0.196 0.373 0.508 0.629 0.745 0.863 0.987 1.111 1.205 1.301 1.361 1.356 1.362 1.472
CV (%) 97.9% 22.7% 15.6% 10.0% 7.8% 9.1% 12.1% 13.2% 13.6% 15.1% 15.5% 18.1% 26.8% 31.0% 33.7%
1964–1990 uses the identical fixed schedule in every year. Annual rows through 2025 retain the actual main-data inputs: observed means at ages 3–15+ where available, with model-predicted fills for 2025 ages 13 and 14. The 2026 ages 3–15+ are the selected standalone WtAgeRE predictions.
Ages 1–2 in 2025 and 2026 retain the 2024 input values. Forecast rows 2027–2028 have blank ages 1–2 because that annual model estimates ages 3–15+ only. Blank cells indicate unavailable estimates. Future rows use the selected standalone WtAgeRE fishery forecasts. Projections hold the 2027 forecast fixed for catch and spawning weights. Detailed source records are in the technical appendix.
Mean and CV use the 35 main-input schedules from 1991–2025, including the identified fills and younger-age values retained from the baseline. The fixed early row and all 2026–2028 predictions/forecasts are excluded. CV = sample SD / mean, expressed as percent; it describes variation in the weight schedules among years.
Table 29: Effects of cumulative input updates within Model 23.0, expressed as 2026 estimates. Biomass uses the same reference population weight schedule in every fit, and fishing mortality is the maximum realized rate across ages. Each row includes preceding updates. ATS and AVO contrasts combine new observations, historical revisions and the stated uncertainty calibrations; the fits estimate their combined effect.
Input updates within Model 23.0
Cumulative input update Biomass (million t) Spawning biomass (million t) Age-1 fish (billion) Fishing mortality (per year)
Catch + endpoint 9.030 2.623 18.525 0.348
+ Fishery weights 2024 8.856 2.542 18.541 0.348
+ Fishery weights 2026 8.857 2.533 18.541 0.348
+ Fishery age data 9.323 2.746 18.523 0.341
+ BTS 9.966 2.834 24.345 0.335
+ ATS 11.043 2.761 31.731 0.345
+ AVO 11.227 2.808 31.948 0.341
Table 30: Deterministic 2026 population estimates with the selected catch inputs. Model 26.1.2 is the Early-late fishery split comparison; its marginal sampling estimator is excluded.
2026 estimates after the catch revision
Model Biomass (million t) Spawning biomass (million t) Age-1 fish (billion) Maximum F (per year)
Model 23.2 12.267 3.031 37.532 0.304
Model 23.0 11.227 2.808 31.948 0.341
Model 26.0 12.162 3.057 36.347 0.299
Model 26.1.0 12.153 3.053 36.334 0.300
Model 26.1.1 12.198 3.064 36.826 0.316
Model 26.1 decline penalty 0 12.351 3.110 37.608 0.338
Model 26.1.2 Early-late fishery split 12.235 3.065 36.518 0.315
ADMB biomass uses the same population weights as Model 26.0. Model 26.1.2 is a deterministic native joint mode conditional on fixed Foreign and Modern SDs; its sampling-based marginal estimator was excluded by author instruction. This table presents point estimates; scientific model adoption remains separate.
Table 31: Model 26.0 estimated population quantities in 2026. Ranges are approximate 95% confidence intervals under the selected model and fixed biological schedules. Fishing mortality is the largest realized rate across ages in 2026.
Estimated 2026 population
Quantity Estimate SE 95% lower 95% upper Units
Total biomass 12.162 1.511 9.534 15.515 Million tons
Spawning biomass 3.057 0.320 2.489 3.754 Million tons
Age-1 recruitment 36.347 19.395 12.772 103.440 Billion fish
Fishing mortality: most exposed age 0.299 0.067 0.194 0.463 Per year
Table 32: Model 26.0 annual estimates and approximate 95% confidence intervals, 1964–2026. Each cell gives the estimate followed by its 95% interval. Biomass and spawning biomass are million tons, recruitment is billion age-1 fish and fishing mortality is the maximum realized rate across ages per year. Recruitment is labeled by the calendar year fish enter age 1.
Annual population estimates and 95% intervals
Year Biomass (million t) Spawning biomass (million t) Age-1 fish (billion) Fishing mortality (per year)
1964 4.827 (3.351–6.953) 1.348 (0.909–1.998) 5.727 (2.316–14.165) 0.077 (0.043–0.135)
1965 5.201 (3.701–7.308) 1.376 (0.939–2.016) 23.494 (13.757–40.121) 0.085 (0.049–0.146)
1966 5.420 (3.893–7.545) 1.398 (0.946–2.067) 15.880 (8.083–31.199) 0.090 (0.053–0.153)
1967 6.159 (4.520–8.392) 1.508 (1.027–2.215) 27.213 (16.078–46.059) 0.161 (0.091–0.286)
1968 6.803 (5.019–9.223) 1.674 (1.131–2.476) 22.441 (12.605–39.953) 0.178 (0.107–0.297)
1969 7.387 (5.544–9.843) 1.895 (1.292–2.781) 26.281 (15.584–44.321) 0.179 (0.104–0.308)
1970 8.087 (6.171–10.599) 2.006 (1.388–2.899) 23.326 (13.486–40.346) 0.265 (0.126–0.556)
1971 8.012 (6.127–10.478) 2.117 (1.476–3.036) 13.629 (6.794–27.342) 0.386 (0.178–0.839)
1972 7.273 (5.512–9.596) 1.978 (1.384–2.825) 10.896 (5.305–22.380) 0.426 (0.196–0.929)
1973 6.521 (4.990–8.522) 1.697 (1.159–2.484) 26.743 (18.276–39.133) 0.471 (0.221–1.005)
1974 5.485 (4.193–7.175) 1.293 (0.834–2.007) 19.281 (13.001–28.596) 0.499 (0.303–0.821)
1975 4.711 (3.663–6.059) 1.200 (0.784–1.835) 16.451 (11.522–23.489) 0.467 (0.327–0.668)
1976 4.304 (3.468–5.342) 1.121 (0.794–1.581) 12.944 (9.258–18.097) 0.423 (0.278–0.643)
1977 4.036 (3.351–4.860) 1.305 (0.984–1.732) 14.023 (10.506–18.716) 0.377 (0.171–0.830)
1978 4.311 (3.700–5.023) 1.158 (0.892–1.504) 26.513 (21.903–32.094) 0.436 (0.197–0.968)
1979 5.530 (4.931–6.200) 1.068 (0.839–1.359) 62.439 (54.916–70.993) 0.462 (0.220–0.969)
1980 6.294 (5.684–6.969) 1.268 (1.044–1.541) 29.662 (24.950–35.264) 0.424 (0.263–0.684)
1981 7.831 (7.139–8.589) 1.934 (1.693–2.210) 34.243 (29.110–40.280) 0.308 (0.201–0.472)
1982 9.443 (8.615–10.352) 2.680 (2.387–3.008) 19.180 (15.520–23.704) 0.201 (0.139–0.291)
1983 10.311 (9.464–11.233) 3.594 (3.219–4.013) 52.001 (46.089–58.672) 0.174 (0.113–0.267)
1984 10.272 (9.441–11.176) 3.732 (3.350–4.158) 14.229 (11.444–17.692) 0.172 (0.130–0.227)
1985 12.273 (11.351–13.271) 4.262 (3.876–4.686) 32.543 (28.408–37.280) 0.181 (0.132–0.249)
1986 11.664 (10.861–12.526) 4.145 (3.805–4.516) 12.743 (10.478–15.497) 0.168 (0.115–0.246)
1987 10.839 (10.212–11.504) 4.157 (3.857–4.480) 7.323 (5.855–9.158) 0.129 (0.086–0.194)
1988 9.780 (9.224–10.370) 3.909 (3.657–4.179) 5.712 (4.552–7.168) 0.181 (0.122–0.268)
1989 8.195 (7.706–8.714) 3.382 (3.165–3.613) 11.908 (10.240–13.848) 0.209 (0.159–0.275)
1990 7.731 (7.305–8.183) 2.870 (2.674–3.080) 50.462 (46.960–54.226) 0.292 (0.214–0.396)
1991 8.525 (8.086–8.988) 2.320 (2.144–2.511) 27.363 (24.774–30.224) 0.406 (0.289–0.569)
1992 9.146 (8.688–9.628) 2.202 (2.049–2.366) 23.766 (21.304–26.512) 0.484 (0.330–0.711)
1993 10.389 (9.875–10.931) 2.878 (2.704–3.063) 46.285 (42.750–50.113) 0.304 (0.211–0.438)
1994 10.238 (9.733–10.769) 3.341 (3.143–3.551) 15.931 (14.075–18.031) 0.233 (0.157–0.346)
1995 8.867 (8.408–9.350) 3.572 (3.367–3.790) 11.171 (9.736–12.818) 0.296 (0.252–0.348)
1996 9.339 (8.859–9.845) 3.509 (3.307–3.723) 22.654 (20.657–24.844) 0.376 (0.308–0.458)
1997 8.875 (8.422–9.352) 3.412 (3.210–3.626) 30.307 (28.043–32.753) 0.339 (0.229–0.504)
1998 8.748 (8.302–9.217) 2.901 (2.726–3.087) 14.951 (13.463–16.604) 0.275 (0.199–0.380)
1999 8.937 (8.494–9.403) 3.020 (2.847–3.204) 16.029 (14.509–17.708) 0.213 (0.180–0.251)
2000 9.070 (8.635–9.528) 2.903 (2.741–3.075) 24.585 (22.686–26.642) 0.272 (0.224–0.330)
2001 9.067 (8.643–9.512) 2.939 (2.776–3.113) 34.415 (32.234–36.744) 0.291 (0.239–0.354)
2002 9.528 (9.109–9.966) 2.728 (2.577–2.889) 22.938 (21.267–24.742) 0.374 (0.318–0.440)
2003 10.763 (10.308–11.238) 2.748 (2.605–2.899) 14.341 (13.115–15.681) 0.415 (0.338–0.510)
2004 9.630 (9.214–10.065) 3.032 (2.882–3.189) 6.525 (5.751–7.404) 0.361 (0.279–0.467)
2005 7.764 (7.409–8.136) 2.663 (2.529–2.804) 4.624 (3.988–5.362) 0.335 (0.282–0.399)
2006 6.805 (6.471–7.156) 2.431 (2.302–2.567) 11.539 (10.424–12.774) 0.406 (0.348–0.474)
2007 6.328 (6.007–6.666) 1.994 (1.876–2.119) 24.986 (23.081–27.048) 0.432 (0.370–0.505)
2008 4.826 (4.568–5.099) 1.528 (1.427–1.636) 13.553 (12.109–15.170) 0.443 (0.372–0.528)
2009 5.899 (5.593–6.221) 1.617 (1.512–1.730) 49.521 (46.316–52.948) 0.381 (0.256–0.569)
2010 7.701 (7.321–8.101) 1.654 (1.549–1.767) 23.135 (21.102–25.363) 0.317 (0.237–0.425)
2011 8.485 (8.068–8.924) 2.029 (1.907–2.158) 14.211 (12.693–15.910) 0.433 (0.356–0.526)
2012 8.811 (8.359–9.287) 2.475 (2.331–2.628) 12.310 (10.960–13.827) 0.429 (0.266–0.691)
2013 9.756 (9.251–10.287) 2.824 (2.655–3.003) 43.285 (40.546–46.208) 0.428 (0.253–0.723)
2014 10.381 (9.869–10.919) 2.782 (2.606–2.969) 49.480 (46.207–52.984) 0.403 (0.226–0.719)
2015 11.568 (11.013–12.151) 2.597 (2.436–2.768) 21.258 (19.132–23.620) 0.449 (0.245–0.823)
2016 12.325 (11.722–12.960) 2.855 (2.690–3.030) 8.625 (7.265–10.239) 0.312 (0.244–0.400)
2017 11.425 (10.826–12.056) 3.300 (3.110–3.502) 7.890 (6.545–9.511) 0.295 (0.211–0.414)
2018 9.899 (9.330–10.502) 3.152 (2.957–3.361) 16.823 (14.472–19.557) 0.276 (0.232–0.329)
2019 10.741 (10.071–11.457) 3.067 (2.851–3.299) 87.831 (78.998–97.651) 0.438 (0.360–0.532)
2020 11.795 (10.940–12.717) 2.364 (2.171–2.575) 27.572 (23.257–32.688) 0.419 (0.353–0.497)
2021 11.818 (10.823–12.905) 2.619 (2.394–2.866) 12.958 (9.881–16.992) 0.416 (0.332–0.523)
2022 13.137 (11.866–14.545) 3.742 (3.383–4.139) 12.683 (9.030–17.815) 0.291 (0.220–0.385)
2023 11.901 (10.613–13.345) 3.779 (3.369–4.238) 11.616 (7.811–17.274) 0.232 (0.155–0.348)
2024 10.767 (9.397–12.337) 3.526 (3.076–4.041) 39.254 (25.030–61.560) 0.243 (0.201–0.294)
2025 10.134 (8.563–11.993) 3.228 (2.732–3.814) 27.976 (16.327–47.937) 0.293 (0.225–0.380)
2026 12.162 (9.534–15.515) 3.057 (2.489–3.754) 36.347 (12.772–103.440) 0.299 (0.194–0.463)
Table 33: Final 2026 population summaries from the regularized Model 26.0 posterior. All 5,000 saved draws contribute. Intervals are central 95% credible intervals. Priors, parameter support and biology remain fixed. Production-fit estimates and projections retain their separate roles.
Posterior population uncertainty
Quantity and units Mean Median 2.5% 97.5%
SSB 2026 (million t) 2.9645 2.9465 2.4497 3.5844
Biomass 2026 (million t) 11.5860 11.4616 9.2151 14.7192
Recruitment 2026 (billion fish) 36.4680 31.1518 12.2880 91.0616
Table 34: Model 26.0 start-of-year numbers at age, 1964–2026, in billion fish. Age 15+ includes all older fish. Values are rounded to 0.001 billion fish; full precision is retained in the supporting tables.
Numbers at age (billion fish)
Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15+
1964 5.727 4.350 2.577 0.877 0.514 0.633 0.390 0.247 0.198 0.173 0.149 0.127 0.106 0.088 0.159
1965 23.494 2.328 2.763 1.872 0.612 0.356 0.434 0.269 0.171 0.137 0.120 0.104 0.089 0.074 0.172
1966 15.880 9.549 1.476 1.987 1.274 0.417 0.243 0.297 0.184 0.117 0.094 0.083 0.072 0.061 0.170
1967 27.213 6.454 6.040 1.053 1.345 0.864 0.283 0.165 0.202 0.125 0.080 0.064 0.057 0.049 0.158
1968 22.441 11.052 4.038 4.077 0.664 0.850 0.548 0.180 0.105 0.129 0.080 0.051 0.041 0.036 0.132
1969 26.281 9.109 6.877 2.693 2.528 0.414 0.533 0.345 0.113 0.066 0.081 0.050 0.032 0.026 0.106
1970 23.326 10.660 5.638 4.445 1.667 1.574 0.259 0.334 0.216 0.071 0.041 0.051 0.031 0.020 0.082
1971 13.629 9.439 6.459 3.435 2.654 0.984 0.930 0.152 0.193 0.124 0.041 0.024 0.029 0.018 0.058
1972 10.896 5.500 5.584 3.709 1.888 1.418 0.529 0.500 0.079 0.100 0.064 0.021 0.012 0.015 0.038
1973 26.743 4.398 3.158 2.995 1.895 0.965 0.726 0.271 0.249 0.039 0.049 0.031 0.010 0.006 0.026
1974 19.281 10.796 2.452 1.583 1.418 0.896 0.457 0.345 0.126 0.116 0.018 0.023 0.014 0.005 0.014
1975 16.451 7.788 5.813 1.103 0.714 0.641 0.407 0.208 0.155 0.057 0.052 0.008 0.010 0.007 0.009
1976 12.944 6.658 4.425 2.700 0.526 0.347 0.314 0.200 0.102 0.077 0.028 0.026 0.004 0.005 0.007
1977 14.023 5.244 3.863 2.220 1.311 0.261 0.174 0.159 0.102 0.052 0.039 0.014 0.013 0.002 0.006
1978 26.513 5.685 3.073 2.134 1.152 0.671 0.135 0.090 0.083 0.053 0.027 0.020 0.007 0.007 0.004
1979 62.439 10.753 3.356 1.697 1.095 0.568 0.333 0.067 0.045 0.041 0.025 0.013 0.009 0.003 0.005
1980 29.662 25.334 6.512 1.953 0.894 0.526 0.271 0.160 0.032 0.021 0.019 0.012 0.006 0.004 0.004
1981 34.243 12.042 15.722 4.120 1.061 0.440 0.255 0.132 0.078 0.016 0.010 0.009 0.006 0.003 0.004
1982 19.180 13.910 7.571 10.735 2.474 0.577 0.240 0.140 0.073 0.043 0.009 0.006 0.005 0.003 0.004
1983 52.001 7.794 8.800 5.406 7.005 1.499 0.350 0.146 0.085 0.044 0.026 0.005 0.003 0.003 0.004
1984 14.229 21.135 4.935 6.345 3.678 4.454 0.933 0.219 0.091 0.053 0.028 0.017 0.003 0.002 0.005
1985 32.543 5.783 13.399 3.558 4.364 2.346 2.778 0.583 0.137 0.057 0.033 0.017 0.010 0.002 0.004
1986 12.743 13.228 3.666 9.626 2.464 2.876 1.450 1.721 0.363 0.086 0.036 0.021 0.011 0.007 0.004
1987 7.323 5.180 8.390 2.635 6.620 1.641 1.821 0.908 1.088 0.229 0.054 0.023 0.013 0.007 0.007
1988 5.712 2.977 3.291 6.063 1.859 4.529 1.089 1.207 0.591 0.709 0.150 0.036 0.015 0.009 0.009
1989 11.908 2.322 1.889 2.308 4.180 1.215 2.892 0.674 0.753 0.369 0.446 0.095 0.023 0.009 0.011
1990 50.462 4.841 1.474 1.348 1.573 2.721 0.768 1.739 0.412 0.467 0.229 0.278 0.059 0.014 0.013
1991 27.363 20.513 3.069 1.051 0.883 0.939 1.582 0.426 0.962 0.232 0.268 0.128 0.158 0.034 0.015
1992 23.766 11.123 13.004 2.212 0.709 0.545 0.550 0.835 0.237 0.517 0.130 0.133 0.065 0.080 0.025
1993 46.285 9.660 7.040 9.058 1.484 0.440 0.299 0.266 0.386 0.109 0.241 0.059 0.061 0.030 0.048
1994 15.931 18.816 6.141 5.016 5.788 0.975 0.266 0.164 0.145 0.212 0.061 0.136 0.033 0.034 0.043
1995 11.171 6.476 11.970 4.488 3.422 3.424 0.588 0.156 0.097 0.087 0.127 0.037 0.082 0.020 0.046
1996 22.654 4.542 4.119 8.785 3.202 2.200 1.886 0.337 0.090 0.057 0.052 0.077 0.022 0.050 0.040
1997 30.307 9.210 2.882 3.010 6.386 2.202 1.297 0.960 0.172 0.049 0.032 0.030 0.045 0.013 0.053
1998 14.951 12.321 5.830 2.098 2.142 4.358 1.377 0.729 0.524 0.091 0.027 0.018 0.017 0.026 0.037
1999 16.029 6.078 7.822 4.233 1.487 1.457 2.659 0.843 0.421 0.295 0.052 0.016 0.011 0.010 0.037
2000 24.585 6.517 3.865 5.567 2.949 1.011 0.946 1.592 0.514 0.259 0.182 0.032 0.010 0.007 0.029
2001 34.415 9.995 4.144 2.792 3.765 1.891 0.648 0.560 0.899 0.307 0.159 0.112 0.020 0.006 0.022
2002 22.938 13.991 6.359 3.017 1.923 2.277 1.047 0.364 0.318 0.524 0.184 0.095 0.068 0.012 0.017
2003 14.341 9.325 8.893 4.605 2.049 1.174 1.160 0.540 0.192 0.175 0.301 0.108 0.057 0.040 0.017
2004 6.525 5.830 5.931 6.270 3.117 1.213 0.615 0.567 0.271 0.102 0.098 0.176 0.063 0.033 0.034
2005 4.624 2.653 3.710 4.296 3.941 1.884 0.684 0.318 0.295 0.147 0.058 0.058 0.105 0.038 0.040
2006 11.539 1.880 1.688 2.690 2.846 2.166 0.998 0.370 0.176 0.165 0.085 0.034 0.035 0.064 0.047
2007 24.986 4.691 1.195 1.193 1.747 1.593 1.069 0.507 0.191 0.093 0.089 0.047 0.020 0.020 0.063
2008 13.553 10.158 2.982 0.845 0.768 0.978 0.766 0.526 0.262 0.101 0.050 0.048 0.026 0.011 0.045
2009 49.521 5.510 6.459 2.150 0.555 0.441 0.465 0.369 0.260 0.132 0.053 0.026 0.025 0.013 0.029
2010 23.135 20.133 3.507 4.643 1.417 0.335 0.226 0.238 0.190 0.135 0.068 0.027 0.013 0.013 0.022
2011 14.211 9.405 12.817 2.564 2.970 0.863 0.197 0.127 0.128 0.103 0.074 0.037 0.014 0.007 0.019
2012 12.310 5.777 5.985 9.326 1.780 1.497 0.415 0.096 0.062 0.063 0.050 0.036 0.019 0.007 0.013
2013 43.285 5.005 3.675 4.338 6.114 1.155 0.723 0.201 0.047 0.031 0.031 0.024 0.018 0.009 0.010
2014 49.480 17.597 3.185 2.667 2.916 3.703 0.691 0.385 0.098 0.023 0.015 0.015 0.012 0.008 0.009
2015 21.258 20.116 11.197 2.315 1.823 1.817 2.084 0.356 0.201 0.051 0.011 0.007 0.008 0.006 0.009
2016 8.625 8.642 12.808 7.777 1.536 1.146 1.015 1.080 0.185 0.105 0.025 0.005 0.004 0.004 0.007
2017 7.890 3.507 5.505 9.386 4.577 0.972 0.694 0.596 0.586 0.103 0.059 0.014 0.003 0.002 0.006
2018 16.823 3.208 2.233 4.045 6.465 2.573 0.548 0.391 0.334 0.323 0.058 0.033 0.008 0.002 0.004
2019 87.831 6.840 2.042 1.641 2.896 3.781 1.446 0.314 0.224 0.194 0.191 0.034 0.020 0.005 0.004
2020 27.572 35.707 4.349 1.497 1.185 1.992 2.008 0.691 0.164 0.123 0.109 0.113 0.020 0.012 0.005
2021 12.958 11.209 22.578 3.140 1.035 0.768 1.044 0.979 0.355 0.082 0.062 0.056 0.060 0.011 0.009
2022 12.683 5.268 7.061 15.644 2.187 0.668 0.471 0.534 0.478 0.181 0.042 0.033 0.030 0.032 0.011
2023 11.616 5.156 3.322 5.072 10.705 1.455 0.427 0.283 0.296 0.276 0.107 0.024 0.019 0.018 0.025
2024 39.254 4.722 3.268 2.384 3.526 6.678 0.891 0.267 0.171 0.174 0.164 0.063 0.014 0.011 0.025
2025 27.976 15.959 3.002 2.342 1.659 2.308 3.879 0.546 0.166 0.104 0.106 0.100 0.038 0.009 0.022
2026 36.347 11.374 10.149 2.172 1.644 1.112 1.276 2.157 0.320 0.098 0.062 0.064 0.060 0.023 0.019
Table 35: Model 26.0 start-of-2026 numbers at age and uncertainty, in billion fish. Ranges are approximate 95% confidence intervals, accounting for covariance in the fitted model. Age 15+ includes all older fish.
2026 numbers at age and uncertainty
Age Estimate SE CV 95% lower 95% upper
1 36.347 19.395 53.4% 12.772 103.440
2 11.374 3.125 27.5% 6.638 19.489
3 10.149 2.335 23.0% 6.466 15.932
4 2.172 0.449 20.7% 1.448 3.259
5 1.644 0.309 18.8% 1.138 2.376
6 1.112 0.184 16.5% 0.804 1.537
7 1.276 0.176 13.8% 0.973 1.672
8 2.157 0.259 12.0% 1.704 2.730
9 0.320 0.045 13.9% 0.243 0.420
10 0.098 0.016 16.6% 0.071 0.136
11 0.062 0.011 18.1% 0.043 0.088
12 0.064 0.012 18.0% 0.045 0.091
13 0.060 0.012 19.7% 0.041 0.089
14 0.023 0.006 25.1% 0.014 0.038
15+ 0.019 0.006 31.3% 0.010 0.034
Table 36: Model 26.0 biological schedules and fishery weight predictions at ages 1–15+, with weights for 2024–2026. Mortality is an annual instantaneous rate; maturity and female fraction are proportions; weights are kg per fish. Population weights are the BTS schedule. Fishery 2026 values show the current predictions; projections use fixed 2027 fishery forecasts for catch and spawning weights.
Biological schedules and recent weights
Age Natural mortality Mature Female
Population weights (kg)
Fishery weights (kg)
Spawning weights (kg)
2024 2025 2026 2024 2025 2026 2024 2025 2026
1 0.900 0.000 0.500 0.017 0.020 0.020 0.025 0.025 0.025 0.085 0.085 0.085
2 0.450 0.008 0.500 0.090 0.079 0.066 0.186 0.186 0.186 0.196 0.196 0.196
3 0.300 0.289 0.500 0.309 0.226 0.397 0.435 0.314 0.368 0.387 0.415 0.317
4 0.300 0.641 0.500 0.454 0.526 0.544 0.481 0.556 0.440 0.452 0.523 0.541
5 0.300 0.842 0.500 0.560 0.587 0.640 0.560 0.621 0.677 0.521 0.596 0.657
6 0.300 0.901 0.500 0.607 0.676 0.725 0.617 0.693 0.734 0.633 0.668 0.732
7 0.300 0.947 0.500 0.693 0.734 0.809 0.696 0.730 0.813 0.750 0.779 0.804
8 0.300 0.963 0.500 0.923 0.812 0.874 0.825 0.855 0.864 0.879 0.893 0.911
9 0.300 0.970 0.500 0.997 0.903 0.949 1.016 0.966 0.953 0.987 1.016 1.019
10 0.300 1.000 0.500 1.020 1.087 1.027 1.017 1.140 1.075 1.055 1.116 1.135
11 0.300 1.000 0.500 1.126 1.066 1.048 1.078 1.194 1.194 1.127 1.175 1.227
12 0.300 1.000 0.500 1.137 1.150 1.192 1.251 1.082 1.232 1.245 1.239 1.279
13 0.300 1.000 0.500 1.259 1.258 1.416 1.308 1.314 1.307 1.294 1.347 1.333
14 0.300 1.000 0.500 1.406 1.399 1.449 1.328 1.343 1.420 1.336 1.388 1.434
15+ 0.300 1.000 0.500 1.754 1.547 1.360 1.559 1.268 1.448 1.391 1.421 1.466
Table 37: Model 26.0 selectivity at age in 2026. Cells give the estimate and approximate 95% confidence interval. ATS and AVO share the same estimated curve. Relative selectivity can exceed one because the existing curve convention uses a different normalization than division by its maximum.
2026 selectivity and uncertainty
Age Fishery BTS ATS and AVO
1 0.000 (0.000–0.003) 0.054 (0.019–0.155) 0.000 (0.000–0.000)
2 0.016 (0.006–0.045) 0.026 (0.012–0.055) 0.776 (0.516–1.169)
3 0.145 (0.055–0.382) 0.066 (0.039–0.112) 0.789 (0.535–1.163)
4 0.337 (0.133–0.852) 0.156 (0.099–0.244) 0.709 (0.483–1.039)
5 0.646 (0.261–1.594) 0.326 (0.207–0.513) 0.779 (0.541–1.122)
6 1.589 (1.018–2.481) 0.559 (0.374–0.836) 0.974 (0.690–1.376)
7 1.556 (1.076–2.249) 0.769 (0.583–1.013) 1.141 (0.831–1.567)
8 1.536 (1.098–2.148) 0.897 (0.770–1.046) 1.125 (0.992–1.275)
9 1.429 (1.042–1.960) 0.958 (0.889–1.033) 1.125 (0.992–1.275)
10 1.354 (0.999–1.837) 0.984 (0.950–1.018) 1.125 (0.992–1.275)
11 1.295 (0.963–1.743) 0.994 (0.979–1.009) 1.125 (0.992–1.275)
12 1.274 (0.937–1.733) 0.998 (0.991–1.004) 1.125 (0.992–1.275)
13 1.274 (0.937–1.733) 0.999 (0.996–1.002) 1.125 (0.992–1.275)
14 1.274 (0.937–1.733) 1.000 (0.998–1.001) 1.125 (0.992–1.275)
15+ 1.274 (0.937–1.733) 1.000 (0.999–1.000) 1.125 (0.992–1.275)
Table 38: Estimated parameter groups and their uncertainty in Model 26.0. Standard errors use each group’s estimation scale; differences in scales make direct comparisons among groups inappropriate.
Estimated parameter groups
Parameter group Count Minimum estimate Maximum estimate Median SE Maximum SE
BTS age-1 deviation 44 −0.401 0.359 0.138 0.211
BTS age-1 log selectivity 1 −3.048 −3.048 0.307 0.307
BTS midpoint deviation 44 −0.351 0.192 0.099 0.123
BTS slope deviation 44 0.246 1.589 0.234 0.398
Initial-age deviation 14 −1.480 −0.395 0.651 0.803
Log catchability 3 −8.225 −0.248 0.071 0.185
Log fishing scale 63 −2.939 −0.821 0.134 0.233
Log logistic slope 1 −0.838 −0.838 0.196 0.196
Logistic midpoint 1 6.981 6.981 0.641 0.641
Recruitment deviation 63 −1.234 1.710 0.142 0.538
Recruitment level 1 9.673 9.673 0.121 0.121
Selectivity increment 987 −1.459 1.287 0.280 0.597
Table 39: Contributions to the Model 26.0 fit, grouped by data source or stabilizing assumption. Rounded rows may differ slightly from their sum. Negative values arise from likelihood constants. Contributions across different data and model structures use different scales and assumptions.
Contributions to the fit
Contribution Value
Catch data −127.771
Composition data 421.207
Index data 160.956
Initial abundance deviates 19.860
Non-parametric selectivity 18.325
Recruitment deviates 71.193
Selectivity deviates 188.221
Table 40: Observed-index residual summaries for Model 26.0. Residuals measure observed-minus-predicted differences relative to the selected observation errors. The retained 2020 ATS placeholders are excluded.
Model 26.0 index residuals
Series Observations Mean residual Residual SD
ATS 20 −0.10 1.04
ATS age 1 19 0.06 1.13
AVO 20 0.12 0.97
BTS 44 0.09 1.19
Historical CPUE 12 0.05 0.53
BTS residuals account for the covariance among survey years. A spread near 1 agrees with the selected observation-error scale. These are fitted-model diagnostics.
Table 41: Model 26.0 profile likelihood points and conditional 2027 female spawning biomass (thousand tons, kt), with approximate 95% confidence intervals. ATS catchability is fixed separately at each point; all other active parameters are re-estimated. The projection assumes 1,375 kt catch in 2027 and the mean 2023–2025 fishery selectivity curve.
2027 female spawning biomass at fixed ATS catchability
ATS q ΔNLL 2027 SSB (kt) Lower 95% (kt) Upper 95% (kt)
0.45000 2.477 3,567.3 2,737.3 4,649.0
0.45837 1.866 3,533.9 2,709.7 4,608.9
0.46674 1.349 3,501.6 2,682.8 4,570.3
0.47510 0.922 3,470.2 2,656.8 4,532.6
0.48347 0.581 3,439.7 2,631.5 4,496.0
0.49184 0.322 3,410.1 2,607.0 4,460.5
0.50021 0.141 3,381.2 2,583.6 4,425.0
0.50858 0.035 3,353.0 2,560.3 4,391.0
0.51694 0.000 3,325.5 2,538.0 4,357.3
0.53358 0.130 3,272.7 2,494.8 4,293.2
0.55021 0.505 3,222.5 2,453.8 4,232.0
0.56684 1.102 3,174.7 2,414.2 4,174.7
0.58347 1.901 3,129.3 2,376.6 4,120.4
0.60010 2.886 3,086.1 2,340.4 4,069.5
0.61674 4.039 3,045.0 2,306.3 4,020.4
0.63337 5.347 3,005.8 2,273.8 3,973.5
0.65000 6.797 2,968.3 2,242.7 3,928.7
Intervals use the fixed-q penalized Hessian and the delta method on log SSB. They propagate fitted-parameter uncertainty, including fitted abundance and selectivity, conditional on the stated catch, biological schedules and ATS q. They exclude uncertainty in ATS q, future recruitment process variation and weight-at-age schedules. Spawning occurs on April 1; age 15+ is retained.
Table 42: Model 26.0 Mohn’s rho against the full-2026 fit. Rho is the mean proportional terminal revision.
Model 26.0 retrospective Mohn's rho
Quantity 2024–2025 (2 peels) 2023–2025 (3 peels) 2017–2025 (9 peels)
Maximum fishing mortality 0.04411 0.15391 −0.06364
Age-1 recruitment −0.26348 0.04013 −0.09848
Total biomass −0.10792 −0.10774 0.00006
Female spawning biomass −0.07636 −0.09393 0.12096
Table 43: Model 26.0 retrospective terminal estimates and revisions: All rows use the full-2026 reference. Each row omits all observations after its terminal year, using the same data-lag rules. Relative revisions are 100 × (peel estimate / full-2026-fit estimate for the same calendar year − 1). SSB is female spawning biomass; F is the maximum age-specific fishing mortality. These are point-estimate comparisons; the peel comparisons cover population estimates only.
Retrospective revisions in Model 26.0
Terminal year F revision (%) Recruitment revision (%) Biomass revision (%) SSB revision (%) Peel SSB (million t) Full-fit SSB (million t)
2025 −9.7 −30.8 −11.0 −4.5 3.08 3.23
2024 18.5 −21.9 −10.5 −10.8 3.15 3.53
2023 37.4 64.7 −10.7 −12.9 3.29 3.78
2022 7.6 −35.0 1.6 2.3 3.83 3.74
2021 34.7 44.6 −9.8 −13.8 2.26 2.62
2020 −35.6 −59.0 −11.0 40.7 3.33 2.36
2019 −53.4 −79.4 0.8 28.2 3.93 3.07
2018 −17.2 −21.3 14.3 26.9 4.00 3.15
2017 −39.5 49.4 36.5 52.8 5.04 3.30
Table 44: Native fitting objectives with the selected catch inputs, including the Early-late fishery split comparison. Model-specific penalties and normalizations preclude direct likelihood ranking.
model objective method
26_0 751.989578 Established deterministic penalized fit
26_1_0 746.780971 Established deterministic penalized fit
26_1_1 726.234542 Established deterministic penalized fit
26_1_decline_zero 706.054843 Established deterministic penalized fit
26_1_2_conditional 731.019469 Early-late fishery split; Foreign 0.1235; Modern fixed at prior marginal estimate
Objectives have model-specific penalties and normalizations. The Early-late fishery split comparison supplies its native joint objective. These values support run verification; direct AIC or likelihood-ratio ranking is excluded.
Table 45: Maximum ABC and OFL for the four separately fitted Rceattle configurations and the Early-late fishery split Model 26.1.2 comparison under matched Scenario 2 assumptions, in million tons. Model 26.0 (Rceattle) is the adopted assessment model and main proposal for Tier 3 calculations and specifications; Model 26.1.2 is the sensitivity analysis. Adopted catch specifications remain separate.
Maximum ABC and OFL under matched Scenario 2 catches
Model
2027
2028
Maximum ABC (difference) OFL Maximum ABC (difference) OFL
Model 26.0 1.896 (+0.00%) 2.328 1.968 (+0.00%) 2.422
Model 26.1.0 1.895 (-0.09%) 2.326 1.966 (-0.09%) 2.420
Model 26.1.1 1.863 (-1.75%) 2.281 1.953 (-0.74%) 2.396
26.1 decline penalty = 0 1.867 (-1.57%) 2.278 1.970 (+0.09%) 2.408
26.1.2 Early-late fishery split 1.855 (-2.19%) 2.269 1.958 (-0.51%) 2.399
Million tons; differences are relative to Model 26.0 in the same year. Recruitment is fixed at each model's historical arithmetic mean. The 26.1.2 row is the Early-late fishery split comparator. Simulation, retrospective and MCMC analyses are excluded. Adopted specifications remain unchanged.
Table 46: Final Model 26.0 posterior stock and selectivity summaries from 5,000 saved draws. SD is posterior standard deviation; intervals are central 95% credible intervals. R-hat and chain ESS describe the saved chains.
Posterior stock and selectivity summaries
Quantity and units Mean Posterior SD Median 2.5% 97.5%
SSB 2026 (million t) 2.9645 0.2928 2.9465 2.4497 3.5844
Biomass 2026 (million t) 11.5860 1.4111 11.4616 9.2151 14.7192
Recruitment 2026 (billion fish) 36.4680 21.2479 31.1518 12.2880 91.0616
Ages1-3 2026 (billion fish) 56.0356 22.4635 50.9012 28.5376 113.5991
BTS selectivity age 1 0.0702 0.0354 0.0635 0.0207 0.1578
BTS selectivity age 2 0.0330 0.0120 0.0314 0.0152 0.0605
BTS selectivity age 5 0.3631 0.0795 0.3541 0.2332 0.5394
BTS selectivity age 10 0.9772 0.0215 0.9839 0.9172 0.9985
BTS selectivity age 15 0.9995 0.0009 0.9999 0.9969 1.0000
Table 47: Reference points for revised Model 26.0 and the Early-late fishery split Model 26.1.2 comparison. Biomass is female spawning biomass in million tons; F is the annual rate on the most selected age. Each column uses that model’s primary projection selectivity and fixed biological schedules.
Quantity Model 26.0 26.1.2 Early-late fishery split Units
B100% 6.158 6.220 Million tons
B40% 2.463 2.488 Million tons
B35% 2.155 2.177 Million tons
F40% 0.513 0.524 Per year
F35% 0.658 0.666 Per year
Revised fits; model-specific 1978–2023 arithmetic mean recruitment. These SPR reference points condition on fixed biology and the stated selectivity window.
Table 48: Projections from the revised fits. Harvest scenarios under the Model 26.0 base fit. Each scenario retains its own rule; specified catches apply only to Scenario 2.
Scenario Rule
1 Fishing at maximum permissible ABC each year.
2 Expected catch of 1,375 kt in 2027 and 2028, followed by maximum permissible ABC; author F fraction 1.
3 Mean annual maximum fishery F over 2021–2025, held constant.
4 One-half the maximum permissible ABC fishing mortality, without fixed-catch conditioning.
5 No fishing.
6 Fishing at the OFL threshold each year.
7 Maximum ABC fishing in 2027 and 2028, followed by OFL fishing from 2029.
Table 49: Projections from the revised fits. Short-term Tier 3 calculations under Scenario 2. Catch, spawning biomass, maximum ABC and OFL are thousand tons; F is the annual rate on the most selected age. The 2028 catch is a planning assumption.
Year Assumed catch Spawning biomass Maximum ABC OFL F
2027 1,375 3,198 1,896 2,328 0.354
2028 1,375 3,394 1,968 2,422 0.341
Table 50: Projections from the revised fits. Thirteen-year catch table for the proposed harvest scenarios, in thousand tons.
Year
Catch (kt) by harvest scenario
1: Maximum ABC 2: Expected catch 3: Recent F 4: Half FABC 5: No fishing 6: OFL 7: ABC, then OFL
2026 1,313 1,313 1,313 1,313 1,313 1,313 1,313
2027 1,896 1,375 1,166 1,026 0 2,328 1,896
2028 1,828 1,375 1,240 1,112 0 2,114 1,828
2029 1,997 2,268 1,460 1,328 0 2,211 2,449
2030 1,900 2,060 1,468 1,351 0 2,047 2,175
2031 1,845 1,933 1,482 1,375 0 1,940 2,015
2032 1,675 1,720 1,384 1,294 0 1,662 1,700
2033 1,602 1,625 1,334 1,251 0 1,603 1,612
2034 1,569 1,580 1,307 1,228 0 1,594 1,596
2035 1,550 1,556 1,289 1,212 0 1,594 1,594
2036 1,541 1,544 1,278 1,202 0 1,595 1,595
2037 1,536 1,538 1,271 1,195 0 1,596 1,595
2038 1,534 1,535 1,267 1,191 0 1,596 1,596
Table 51: Projections from the revised fits. Thirteen-year female spawning-biomass table for the proposed harvest scenarios, in thousand tons.
Year
SSB (kt) by harvest scenario
1: Maximum ABC 2: Expected catch 3: Recent F 4: Half FABC 5: No fishing 6: OFL 7: ABC, then OFL
2026 3,057 3,057 3,057 3,057 3,057 3,057 3,057
2027 3,127 3,198 3,225 3,243 3,366 3,064 3,127
2028 3,123 3,394 3,496 3,569 4,123 2,911 3,123
2029 3,181 3,528 3,774 3,898 4,919 2,871 3,115
2030 2,987 3,188 3,722 3,885 5,348 2,632 2,760
2031 2,815 2,925 3,632 3,823 5,664 2,446 2,508
2032 2,641 2,697 3,475 3,678 5,790 2,302 2,325
2033 2,555 2,585 3,382 3,590 5,904 2,269 2,275
2034 2,510 2,525 3,321 3,530 5,981 2,263 2,263
2035 2,488 2,495 3,286 3,494 6,051 2,263 2,263
2036 2,476 2,480 3,262 3,469 6,091 2,263 2,263
2037 2,470 2,472 3,247 3,452 6,119 2,263 2,263
2038 2,466 2,467 3,237 3,441 6,137 2,263 2,263
Table 52: Thirteen-year fishing-mortality table for the proposed harvest scenarios. F is the annual rate on the most selected age.
Year
F (yr⁻¹) by harvest scenario
1: Maximum ABC 2: Expected catch 3: Recent F 4: Half FABC 5: No fishing 6: OFL 7: ABC, then OFL
2026 0.299 0.299 0.299 0.299 0.299 0.299 0.299
2027 0.513 0.354 0.295 0.257 0.000 0.658 0.513
2028 0.513 0.341 0.295 0.257 0.000 0.658 0.513
2029 0.513 0.513 0.295 0.257 0.000 0.658 0.658
2030 0.513 0.513 0.295 0.257 0.000 0.658 0.658
2031 0.513 0.513 0.295 0.257 0.000 0.653 0.658
2032 0.513 0.513 0.295 0.257 0.000 0.612 0.619
2033 0.513 0.513 0.295 0.257 0.000 0.603 0.605
2034 0.513 0.513 0.295 0.257 0.000 0.601 0.601
2035 0.513 0.513 0.295 0.257 0.000 0.601 0.601
2036 0.513 0.513 0.295 0.257 0.000 0.601 0.601
2037 0.513 0.513 0.295 0.257 0.000 0.601 0.601
2038 0.513 0.513 0.295 0.257 0.000 0.601 0.601
Table 53: Definitions of the nine Model 26.0 catch-decision indicators. All benchmarks are calculated from the Model 26.0 fit.
Probability event Definition Purpose
P(F2027 > F35%) 2027 fishing mortality exceeds the rate giving 35% of unfished spawning potential per recruit. Compare the catch scenario with the Tier 3 reference rate.
P(B2028 < mean B) 2028 female spawning biomass at spawning is below mean estimated SSB over 1978–2025. Compare the following year's stock with its historical mean.
P(B2031 < mean B) 2031 female spawning biomass at spawning is below mean estimated SSB over 1978–2025. Compare medium-term stock condition with its historical mean.
P(B2031 < B2027) 2031 female spawning biomass at spawning is below the first projected-year value under the same scenario. Describe medium-term change relative to 2027.
P(B2029 < B20%) 2029 female spawning biomass at spawning is below 20% of the model-specific unfished reference biomass. Describe the historical low-biomass benchmark used in this decision table; Model 26.0 uses mean-recruitment B100 and ADMB uses stock–recruit Bzero.
P(Y2031 > Yhist) The 2031 abundance ratio of ages 1–5 to ages 6–15+ exceeds the corresponding ratio pooled over 1964–2026. Describe relative abundance of young fish. The historical threshold pools abundance across years, rather than averaging annual proportions.
P(D2028 < D1994) The effective number of mature-biomass age classes in 2028 is below its estimated 1994 value. Describe near-term age diversity relative to a historical low-diversity year.
P(D2031 < D1994) The effective number of mature-biomass age classes in 2031 is below its estimated 1994 value. Describe medium-term age diversity relative to 1994.
P(E2027 > E2026) Mean age-specific fishing mortality in 2027 exceeds mean age-specific fishing mortality in 2026. Provide an F-based relative-effort proxy. Observed vessel effort, catchability changes and costs are outside this indicator.
B denotes female spawning biomass at spawning. Y denotes the young-to-old abundance ratio. D is exp(−sum(p × log(p))), with p the beginning-year mature-biomass age shares. E is the mean-age F proxy. Model-specific biological schedules and reference points are retained.
Table 54: Model 26.0 probabilities under eight alternative 2027 catches (kt), expressed as chances out of 100. Fishing mortality is set to achieve each 2027 catch and then held constant through 2031.
Probability event
2027 catch (kt)
10.0 317.5 635.0 952.5 1270.0 1587.5 1905.0 2540.0
P(F2027 > F35%) 0 0 0 0 0 0 4 73
P(B2028 < mean B) 2 3 6 10 16 23 32 51
P(B2031 < mean B) 0 0 2 6 15 30 52 89
P(B2031 < B2027) 0 1 3 10 27 54 80 99
P(B2029 < B20%) 0 0 0 0 0 0 0 2
P(Y2031 > Yhist) 0 0 0 2 11 27 44 69
P(D2028 < D1994) 0 0 0 0 0 1 1 5
P(D2031 < D1994) 0 0 0 1 2 4 10 41
P(E2027 > E2026) 0 0 0 5 79 99 100 100
Nine supported events. Assessment covariance is propagated through the catch solution, projections and estimated benchmarks. Future recruitment equals the estimated 1978–2023 mean; independent future recruitment innovations and weight-estimation uncertainty are excluded.
Entries are approximate chances out of 100, rounded to whole numbers. A displayed 0 or 100 reflects rounding.

Figures

Five aligned line plots share a 1991-2026 year axis and independent vertical scales. A season is red and solid. B season is turquoise and dashed. Terminal-year points are marked and shaded. The top-to-bottom species order is herring, sablefish, Chinook salmon, chum salmon, and pollock. The sablefish lines break in 2014 because all catch weights are missing. The accompanying data table provides the values, numerator and denominator totals, explicit-zero and missing-entry counts, and coverage dates.
Figure 1: Nominal seasonal catch per tow-hour for herring, sablefish, Chinook salmon, chum salmon, and pollock in EBS pollock-dominated hauls, 1991–2026. Rates equal total extrapolated catch divided by total valid tow-hours. Units are kg per tow-hour for herring and sablefish, tons per tow-hour for pollock, and fish per tow-hour for salmon. A season is January–May; B season is June–December. Hauls are in NMFS areas 500–539, with positive total catch and more than 80% pollock by weight. The 2026 B-season data extend through September 18. Missing species catches are omitted from catch sums while their tow-hours remain in the denominator; unreported species-season combinations appear as gaps. Catcher-vessel and electronic-monitoring coverage is incomplete; catcher-vessel records are absent in 2025–2026 after filtering.
Six time series show sampler-estimated EBS pollock catch numbers, in thousands of fish, for females (circles) and males (triangles) from 1991 to 2025. Red solid lines show January-May A season, blue dashed lines show June-December B season, and green dot-dash lines show their annual sum. Annual numbers fall sharply to a trough around 2009, recover through 2016, and fluctuate thereafter. The 2024 and 2025 estimates are shaded as provisional; annual numbers decline in both sexes in 2025. The accompanying data table gives every plotted value. The 2024–2025 estimates use FT-NIRS ages before conversion to tester ages.
Figure 2: Estimated EBS pollock catch numbers (thousands of fish) by sex for the A season (January–May), B season (June–December), and annual total, 1991–2025. Circles denote females and triangles denote males. B-season estimates combine northwest and southeast areas; annual totals equal A + B. Shading marks provisional 2024–2025 estimates based on released FT-NIRS ages before conversion to thin-section tester ages. Both years cover all 12 months. The estimates have limited age–length coverage: approximately 0.50% and 0.36% of catch biomass, respectively, remain unallocated in unsupported cells.
Four annual series show cumulative catch through the January–April week-ending groups. April values are near 40% before 2017 and generally 43–45% thereafter. In 2026 the January, February, March, and April values are 6.69%, 23.14%, 39.42%, and 43.72%. The accompanying data table contains all 108 plotted values.
Figure 3: Cumulative EBS pollock catch as a proportion of annual specified TAC for weeks ending in January, February, March, and April, 2000–2026. Catch includes retained and discarded pollock from all gears and targets in the Bering Sea subarea, excluding Bogoslof reporting area 518. Each full reporting week is assigned to its week-ending month. The denominator is the annual stock TAC from harvest specifications, before later AI-to-BS quota transfers. Amendment 110 shifted five percentage points of the directed fishery seasonal allocation from B to A to provide greater flexibility to avoid Chinook salmon bycatch; 2017 was the first A season after the rule took effect.
Red circles show A-group roe production and teal triangles show B-group production. The A group remains substantially above the B group across 2000–2026. Provisional 2026 totals are 19,092.9 product metric tons for A and 406.4 tons for the available June–October B-group records. Open terminal markers and dashed links distinguish provisional 2026 values from earlier years. The accompanying data table contains all 54 year-season values.
Figure 4: Pollock roe production for the A (January–May) and B (June–December) seasons, 2000–2026. Data combine at-sea Bering Sea and inshore Bering Sea and Aleutian Islands (BSAI) production. Values are roe product metric tons. Open markers and dashed links identify provisional 2026 values through October 2026.
Spatial distribution of observed pollock catch in the A season, 2024–2026, using January 20–June 9 in each year. Vertical bar height represents catch tons within 0.5-degree longitude by 0.25-degree latitude cells; the height scale is fixed across years within each season, with separate A- and B-season scales and a 10,000-t reference column in each panel. Data are from inseas26.csv and include available catcher-processor, mothership and observed catcher-vessel records in NMFS areas below 540. Electronic-monitoring catcher-vessel records are absent. These are observed-record catch totals rather than fleet-wide expanded catches. The B-season comparison is restricted to the September 18 cutoff in all three years. Rendered with GMT using the AKsf coastline and the local bottom_topo.grd bathymetry grid. Blue shades show ocean depth and green shades show land elevation. Mercator projection viewed at azimuth 155 degrees and elevation 35 degrees, with increased column heights; vertical bars represent catch rather than seafloor height. Updated in the style of Figures 4 and 7 of the 2024 assessment.
Figure 5: Spatial distribution of observed pollock catch in the A season (January 20–June 9), 2024–2026, in each year. Purple vertical bar height represents catch tons within 0.5-degree longitude by 0.25-degree latitude cells; the height scale is fixed across years within each season and a 10,000-t reference column in each panel. Data include available catcher-processor, mothership and observed catcher-vessel records in NMFS areas below 540. Electronic-monitoring catcher-vessel records are absent. The maps show observed-record catch totals rather than fleet-wide expanded catches. Blue shades show ocean depth and green shades show land elevation.
Spatial distribution of observed pollock catch in the B season, 2024–2026, using June 10–September 18 in each year. Vertical bar height represents catch tons within 0.5-degree longitude by 0.25-degree latitude cells; the height scale is fixed across years within each season, with separate A- and B-season scales and a 10,000-t reference column in each panel. Data are from inseas26.csv and include available catcher-processor, mothership and observed catcher-vessel records in NMFS areas below 540. Electronic-monitoring catcher-vessel records are absent. These are observed-record catch totals rather than fleet-wide expanded catches. The B-season comparison is restricted to the September 18 cutoff in all three years. Rendered with GMT using the AKsf coastline and the local bottom_topo.grd bathymetry grid. Blue shades show ocean depth and green shades show land elevation. Mercator projection viewed at azimuth 155 degrees and elevation 35 degrees, with increased column heights; vertical bars represent catch rather than seafloor height. Updated in the style of Figures 4 and 7 of the 2024 assessment.
Figure 6: Spatial distribution of observed pollock catch in the B season (June 10–September 18), 2024–2026, in each year. Purple vertical bar height represents catch tons within 0.5-degree longitude by 0.25-degree latitude cells; the height scale is fixed across years within each season and a 10,000-t reference column in each panel. Data include available catcher-processor, mothership and observed catcher-vessel records in NMFS areas below 540. Electronic-monitoring catcher-vessel records are absent. The maps show observed-record catch totals rather than fleet-wide expanded catches. Blue shades show ocean depth and green shades show land elevation.
A- and B-season mean pairwise tow distances from 2000 through 2026. A-season dispersion rises in 2025 and falls in 2026. B-season dispersion declines from 2024 through 2026 under the common September 18 cutoff.
Figure 7: Fleet dispersion in the A and B seasons, 2000–2026 using a daily pairwise-distance approach. Unique tow pairs are formed within each day and vessel group (catcher-processors and observed catcher vessels); seasonal means pool distance sums and pair counts across both groups. No cross-group pairs are included. Distances are great-circle nautical miles. Solid lines use available seasonal records; dashed lines use records occurring between January 1 and September 18. The 2026 B season is partial. Tows included caught more than 80% pollock by catch weight, had valid locations, occurred in EBS reporting areas 500–539, and had tow durations between zero and 40 hours. Duration is calculated from timestamps with recorded minutes as fallback. Electronic-monitoring catcher-vessel records are absent.
Catch-weighted distributions of mean pollock weight per source record for A and B seasons, 1991–2026. Catch tons are grouped in 50-g bins; the vertical line marks 500 g. A is source week 24 or earlier and B is later than week 24. The extract ends September 18, 2026, so B-season coverage is partial. Available catcher-vessel records exclude electronic-monitoring records. Ridges describe the distribution of record means, with heights scaled for display.
Figure 8: Catch-weighted distributions of mean pollock weight per individual for A and B seasons, 1991–2026. Catch tons are grouped in 50-g bins; the vertical line marks 500 g. The 2026 B-season coverage includes data up to September 18. Available catcher-vessel records exclude electronic-monitoring records. Ridges describe the distribution of the mean individual weight by haul.
Weekly A-season-window distributions of mean pollock weight, 2001–2026, for source weeks 2–15. Catch tons are grouped in approximately 66.7-g bins; the vertical line marks 500 g. Source weeks are seven-day periods beginning January 1. The window differs from the regulatory A season. Available catcher-vessel coverage is incomplete.
Figure 9: Weekly A-season (defined here as weeks 2–15) distributions of mean pollock weight, 2001–2026. Catch tons are grouped in approximately 66.7-g bins; the vertical line marks 500 g. Available catcher-vessel coverage is incomplete.
Weekly B-season-window distributions of mean pollock weight, 2001–2026, for source weeks 25–40. Catch tons are grouped in approximately 66.7-g bins; the vertical line marks 500 g. The 2026 data extend through September 18 and therefore covers only part of this window. Available catcher-vessel coverage is incomplete.
Figure 10: Weekly B-season (defined here as weeks 25–40) distributions of mean pollock weight, 2001–2026. Catch tons are grouped in approximately 66.7-g bins; the vertical line marks 500 g. The 2026 series extends through September 18 and covers only part of this window. Available catcher-vessel coverage is incomplete.
Annual stacked bars show EBS pollock catch from 1964 through 2026 in million tons. The 1964–1990 bars are neutral gray historical totals with no seasonal or regional split. From 1991, blue SE B-season bars are below green NW B-season and orange A-season bars. A dashed line separates the source periods; the final bar shows partial 2026 catch through October 17.
Figure 11: Eastern Bering Sea pollock catch, 1964–2026, in million tons. Catches for 1964–1990 are undifferentiated by season and area; from 1991–2026 the A-season catches (January–June) are undifferentiated by area, while the B-season catches (June–December) are shown separately by area (NW and SE). The NW area comprises NMFS areas 520–529; SE comprises 500–517 and 519. The 2026 bar includes 1.268 million tons of catch through October 17 and is incomplete.
Eight annual maps compare pollock bottom-trawl CPUE with labeled 0, 2 and 4 degree Celsius isotherms. Large CPUE patches occur on the western and southern shelf and shift among years, with several patches near the 2 degree contour in 2022, 2024 and 2026. Central and northern cold-water areas vary in extent; blue points identify sampled tows. The visual association includes depth, coverage and other ecological influences.
Figure 12: EBS bottom-trawl survey (BTS) pollock CPUE and bottom-temperature contours, 2018–2026 (no survey was conducted in 2020), reproduced from the AKsf R-package’s pollock-mapping example (Ianelli 2026). Blue points mark sampled tows; contours are labeled 0, 2 and 4 °C. Surfaces are descriptive local interpolations within survey coverage, with no spatial prediction intervals. The CPUE includes a density-dependent correction whose version and adoption status are unspecified in the example.
Stacked annual length distributions show changing small-fish peaks near 10–17 cm and larger-fish peaks near 35–50 cm. Peaks shift among years. The distributions use a relative abundance scale.
Figure 13: BTS abundance at length on a relative scale, 1987–2026. The BTS was not conducted in 2020.
Perspective bar chart shows changing BTS age distributions. The 1992, 2012 and 2018 year classes progress diagonally through increasing ages. The 2018 year class reaches age 8 in 2026. The 2020 survey row is blank.
Figure 14: BTS age composition by year, 1990–2026. Highlighted bars trace the 1992 (green), 2012 (blue) and 2018 (red) year classes as they advance through successive ages. The BTS was not conducted in 2020.
Perspective bar chart shows changing ATS age distributions and cohorts advancing through age groups. The highlighted 2018 year class appears at age 4 in 2022, age 6 in 2024 and age 8 in 2026. Ages 2 and 3 dominate the provisional 2026 distribution.
Figure 15: ATS age composition by year, 1994–2026. Blank rows indicate years without age-composition observations. Highlighted bars trace the 2014 (green) and 2018 (red) year classes. The 2026 ages are provisional estimates derived by applying the BTS age–length key to ATS population length frequencies.
Two bar charts show provisional core-area ATS abundances. The FT-NIRS length-key product peaks at age 2 at 5.341 billion fish. Conditional conversion to TMA tester ages shifts the largest bar to age 3 at 3.958 billion, with age 2 at 3.729 billion. Both panels allocate 12.662522 billion fish.
Figure 16: Provisional core-area 2026 ATS abundance-at-age after applying a BTS FT-NIRS length key (upper panel) and the screened 307-pair BTS conditional tester-age key (lower panel). Bars show billion fish over observed lengths only, with no uncertainty intervals. The analysis uses supported 1-cm length bins; the 307-pair tester-age key excludes flagged calibration outliers.
Line chart of provisional ATS mean weight in kilograms per fish at TMA ages 1 to 15+. Values rise from 0.0442 at age 1 to 1.1832 at age 14, with 1.1320 for the pooled 15+ group. The values use only supported lengths and have no uncertainty intervals.
Figure 17: Provisional core-area 2026 ATS mean weight-at-age using TMA tester age, obtained by dividing biomass by estimated (converted) abundance-at-age. The 15+ point includes ages 15–18. These point estimates cover observed lengths only.
Nineteen maps show pollock biomass in kilograms for survey years 1994, 1996, 1997, 1999, 2000, 2002, 2004, 2006, 2007, 2008, 2009, 2010, 2012, 2014, 2016, 2018, 2022, 2024, and preliminary 2026. Purple-to-yellow bins show increasing biomass; geographic patterns vary across the EBS shelf. The bottom three metres are excluded.
Figure 18: ATS pollock biomass between near surface and 3.0 m above the bottom, 1994–2026. Biomass between 3.0 m and the seafloor is excluded. The legend gives biomass in kg.
Eastern Bering Sea ATS core-shelf pollock biomass from 1994 through 2026. Biomass is lowest in 2008–2009, highest in 2014–2016, and increases from 2.875 million tons in 2024 to preliminary 3.682 million tons in 2026. Approximate 95 percent intervals use survey relative errors available for all 20 observed years. The Northern Extension is excluded.
Figure 19: ATS core-shelf biomass (dots) and corresponding approximate asymptotic normal 95% intervals (vertical bars), 1994–2026. The line connects observed survey estimates.
GMT contour map of mean 2026 ATS biomass per survey interval, including the Northern Extension. The highest values occur along the western shelf and shelf edge. Labeled black contours mark 1000 and 2000 tons per EDSU; light-blue water lies outside the observation-support mask.
Figure 20: Preliminary 2026 ATS pollock distribution, including the Northern Extension. Colors and GMT contours show gridded mean interval biomass (tons per EDSU), using all 10,924 observations. Approximately 10-nautical-mile cell means are smoothed and displayed within 30 km of sampled cell centers. Dashed gray lines mark 100 and 200 m depths. Coastline: AKsf.
A single time-series plot of annual AVO relative backscatter and 95 percent confidence intervals. The index rises from about 0.30 in 2009 to 1.55 in 2015, then fluctuates near 1. There is no 2020 observation. The 2026 value is 1.118 with CV 4.55 percent.
Figure 21: Annual AVO relative backscatter index for 2009–2026, with the 95% confidence intervals rescaled by the same mean. The dashed line marks a relative index of 1. The line has a gap at 2020; the orange triangle identifies 2026.
Twenty annual map panels span 2006–2026, including legacy 2006–2008 observations. Twenty years show GMT contours and colors of mean AVO backscatter on a common scale. The year 2020 is omitted because AVO observations are unavailable. Labeled contours and the AKsf coastline show shifting concentrations along the shelf.
Figure 22: AVO pollock backscatter, 2006–2026 (m²/nmi²), mapped with common GMT gridding and contour levels. Twenty survey years are shown; AVO observations are unavailable for 2020. Cell means include observed zeros and use an approximately 20-nautical-mile grid. Surfaces are displayed within 45 km of sampled cell centers. Dashed gray lines mark 100 and 200 m depths. Coastline: AKsf. The 2026 observations are preliminary.
Three heatmaps for 2014–2028 compare observed fishery weights, observed BTS weights, and predicted fishery-scale weights. Observations end in 2025. The 2026 age-3 cohort has predicted weights of 0.37 kg in 2026, 0.48 kg at age 4 in 2027, and 0.60 kg at age 5 in 2028. Boundaries identify 2026 and forecast years.
Figure 23: Observed and predicted weight-at-age, 2014–2028, after omitting 2026 BTS weight observations from the standalone random-effects fit. Cell labels give mean weight in kg per fish for ages 3–10. Fishery and BTS observations end in 2025; the right-hand panel includes 2026 estimates without weight observations and 2027–2028 forecasts. The solid line marks 2026; dashed boxes mark forecast years. Colours show proportional deviations from each age’s mean through 2025 within its own panel, saturating at ±50%. Blank cells indicate absent observations, including the 2020 BTS gap.

Download the figure data and anomaly reference means.

Four panels compare seven cumulative input updates for biomass at common weights, spawning biomass, age-1 recruitment and maximum fishing mortality. Colors and line patterns distinguish the updates. Annual CSVs accompany the figure.
Figure 24: Cumulative input-update comparisons within Model 23.0, 2000–2026. Each fit includes the preceding updates. Biomass uses the same population-weight schedule in every comparison, and fishing mortality is the maximum realized rate across ages. ATS and AVO updates combine observations, historical revisions and observation-error calibrations. Lines show point estimates.
Two column charts show Catch plus 2026 endpoint, Fishery age data, bottom-trawl survey, acoustic-trawl survey and AVO in order. The upper panel shows projected spawning biomass and the lower panel stacks ages 1–3. Fits use estimated 2026 catch of 1,310,000 tons.
Figure 25: Projected 2027 spawning biomass and combined abundance at ages 1–3 across five selected cumulative Model 23.0 input-update stages. These comparisons use estimated annual 2026 catch of 1,310,000 t. The displayed stages are cumulative; the omitted weight-at-age and A-season spawning-weight updates remain included in the fishery-age and later stages. Lower-panel columns stack ages 1, 2 and 3 at the start of 2027, before removals; spawning biomass includes mortality to spawning time. Projection methods are described in the technical supplement.
Seven distributions show the five selected cumulative stages, then Models 23.2 and 26.0. They retain the saved 2027-minus-2026 spawning biomass changes and matching uncertainty. The first label is Catch plus 2026 endpoint, followed by Fishery age data. The fitted 2026 catch is 1,310,000 tons.
Figure 26: Approximate distributions of spawning-biomass change from 2026 to 2027 across five selected cumulative input-update stages, followed by Models 23.2 and 26.0 fitted to the same assessment data. These comparisons use estimated annual 2026 catch of 1,310,000 t. The displayed stages are cumulative; the omitted weight-at-age and A-season spawning-weight updates remain included in the fishery-age and later stages. Green area represents an increase and orange area a decrease. Dots show estimated changes, bars show 95% local asymptotic ranges, and labels give approximate chances of an increase rounded to whole percentages. Distributions use fitted parameter covariance; projection methods are described in the technical supplement.
Seven distributions compare the saved 2026-minus-2025 changes in total abundance at ages 1–4. The first two labels are Catch plus 2026 endpoint and Fishery age data, followed by three survey updates and Models 23.2 and 26.0. All matching uncertainty summaries are preserved.
Figure 27: Approximate distributions of change from 2025 to 2026 in total numbers at ages 1–4. Five selected cumulative input-update stages are followed by Models 23.2 and 26.0 fitted to the same assessment data. The displayed stages are cumulative; the omitted weight-at-age and A-season spawning-weight updates remain included in the fishery-age and later stages. Annual totals sum ages 1–4 at the start of the year and account for cross-age and cross-year parameter covariance. Green area represents an increase and orange area a decrease. Dots show estimates, bars show 95% uncertainty ranges and labels give approximate chances of an increase.
Four panels compare Models 23.0 and 23.2 from 1964 through 2026, with uncertainty shading. Common weights and maximum-age fishing mortality provide matched quantity definitions. Annual values and intervals accompany the figure.
Figure 28: Models 23.0 and 23.2 fitted to the same observations and biological schedules. Lines show annual estimates and shading gives approximate 95% local asymptotic uncertainty ranges. Panels show biomass at common population weights, spawning biomass, age-1 recruitment and maximum realized fishing mortality across ages.
Four panels compare Models 23.2 and 26.0 from 1964 through 2026. Blue dashed and orange solid lines distinguish the models, with uncertainty shading. Annual estimates, errors and intervals use matched quantity definitions.
Figure 29: Models 23.2 and 26.0 fitted to the same observations and biological schedules. Lines show annual estimates and shading gives approximate 95% local asymptotic uncertainty ranges. Panels show biomass at common population weights, spawning biomass, age-1 recruitment and maximum realized fishing mortality across ages. These estimation ranges are conditional on the stated model and inputs.
Model 26.0 annual total biomass, female spawning biomass, age-1 recruitment and fishing mortality through 2026, with approximate 95% asymptotic estimation ranges. Total biomass uses population weights; spawning biomass uses mature female spawning weights and survival to spawning. Recruitment is labeled by the year fish enter age 1; fishing mortality is the maximum realized rate across ages. Biological schedules are fixed.
Figure 30: Model 26.0 annual total biomass, female spawning biomass, age-1 recruitment and fishing mortality through 2026, with approximate 95% asymptotic estimation ranges. Total biomass uses population weights; spawning biomass uses mature female spawning weights and survival to spawning. Recruitment is labeled by the year fish enter age 1; fishing mortality is the maximum realized rate across ages. Biological schedules are fixed.
Model 26.0 start-of-year numbers at age, 1964–1989, followed by 1990–2026 as the same figure continued. The color legend shows multiples of the age-specific mean. Cells show abundance as multiples of each age-group mean, rounded to one decimal place, with asymptotic CV (%) in parentheses. Each age-group mean uses the full 1964–2026 period. Ages 10–14 and 15+ are pooled once into 10+; its SE uses the summed saved Jacobian and full matching parameter covariance. Both pages use identical scales, denominators and cell sizing.
Figure 31: Model 26.0 start-of-year numbers at age, 1964–2026, displayed across two pages. Cells show abundance relative to each age group’s 1964–2026 mean, rounded to one decimal place, with asymptotic CV (%) in parentheses. Ages 10–14 and 15+ are pooled into 10+; its SE accounts for the full fitted parameter covariance. Both pages use the same scales and cell sizes.

Figure 31 (continued): 1990–2026. Age groups, full-period denominators, scales and row sizing match the preceding page.

Continuation of the Model 26.0 abundance-at-age display for 1990–2026, with the same full-period age-group means, scales and asymptotic CV definitions as the first page.

Age-1 recruitment from the accepted 2024 assessment, Model 23.0, compared with Models 26.0 (panel A) and 26.1.2 (panel B). Bars show point estimates for both sexes in billions of fish. Historical estimates are repeated unchanged without intervals. Whiskers show local 95% log-scale intervals: the native asymptotic covariance for Model 26.0 and the marginal fit’s Louis observed information for Model 26.1.2, conditional on its integration samples and normalizer grid. Calendar year denotes age 1; the 2018 year class enters at age 1 in 2019.
Figure 32: Age-1 recruitment from the accepted 2024 assessment, Model 23.0, compared with Models 26.0 (panel A) and 26.1.2 (panel B). Bars show point estimates for both sexes in billions of fish. Historical estimates are shown without intervals. Whiskers show local 95% log-scale intervals: the native asymptotic covariance for Model 26.0 and the marginal fit’s Louis observed information for Model 26.1.2, conditional on its integration samples and normalizer grid. Calendar year denotes age 1; the 2018 year class enters at age 1 in 2019.
2024 and 2026 spawning-biomass estimates and Scenario 2 projections through 2028. The current projection reaches 3,394 kt in 2028, with an approximate 95% assessment-parameter interval of 2,363–4,875 kt.
Figure 33:Female spawning biomass estimated and projected by the 2024 assessment (Model 23.0) and the 2026 assessment (Model 26.0), through 2028. Solid lines show estimates; dashed lines and points show Scenario 2 projections. The 2024 series reproduces published Tables 26 and 32, with planned catches of 1,350 kt in 2025–2026 followed by maximum ABC. The current projection uses 1,375 kt in 2027–2028. Shading shows approximate 95% log-scale delta-method intervals for current assessment-parameter uncertainty, conditional on fixed weights and mean future recruitment; independent future recruitment and weight-estimation uncertainty are excluded. No corresponding 2024 uncertainty band is shown. Dotted lines mark the assessment endpoints, 2024 and 2026.
Two panels show log recruits per spawner through time and against female spawning biomass. Recruitment is matched to the preceding spawning year. The 1978, 2008 and 2018 cohorts have high ratios; recent cohorts are highlighted in orange.
Figure 34: Model 26.0 log recruits per spawner. Age-1 recruits in year t+1 (million fish) are divided by female spawning biomass in year t (thousand tons), then natural-log transformed. The numerical ratio is recruits per kilogram of female spawning biomass. Upper panel: birth-year series, 1964–2025. Lower panel: the same ratios against spawning biomass, with two-digit birth-year labels and lines joining consecutive years. Orange identifies the less certain 2023–2025 year classes. The figure shows point estimates of the ratio.
Model 26.0 biological and selectivity schedules. Maturity, female fraction and natural mortality are inputs. The weight panel distinguishes the 2026 population (BTS), spawning and fishery schedules from the selected 2027 fishery forecast used for both catch and spawning in projections. The 2026 fishery estimates and 2027 forecast come from the standalone WtAgeRE fit omitting 2026 BTS weight observations; population and historical spawning weights retain their separate treatments. Fishing and survey selectivity curves have approximate 95% asymptotic ranges; ATS and AVO share their estimated curve. Schedules have no fitted-parameter bands.
Figure 35: Model 26.0 biological and selectivity schedules. Maturity, female fraction and natural mortality are inputs. The weight panel distinguishes the 2026 population (BTS), spawning and fishery schedules from the selected 2027 fishery forecast used for both catch and spawning in projections. The 2026 fishery estimates and 2027 forecast come from the standalone WtAgeRE fit omitting 2026 BTS weight observations; population and historical spawning weights retain their separate treatments. Fishing and survey selectivity curves have approximate 95% asymptotic ranges; ATS and AVO share their estimated curve. Schedules have no fitted-parameter bands.
Model 26.0 instantaneous fishing mortality by age through 2026, using the verified fit. Tiles and contours show the same realized total fishing mortality rates; age 15+ remains the terminal group.
Figure 36: Model 26.0 instantaneous fishing mortality by age through 2026. Tiles and contours show the same realized total fishing mortality rates; 15+ is the terminal age group.
Spawning exploitation over 63 whole-year intervals. Solid black shows revised production-fit values; dashed blue shows posterior medians with a central 95 percent shaded interval. Terminal values and assumptions appear in the caption.
Figure 37: Model 26.0 spawning exploitation for spawning-to-spawning intervals starting in 1964–2026. Black lines show the Model 26.0 fit; dashed blue lines and shading show MCMC posterior medians and central 95% credible intervals from 5,000 draws. Each within-draw ratio compares next-spawning biomass with and without fishing from a shared spawning-date population. The terminal interval assumes 1.375 million t catch in 2027, within-draw mean 1978–2023 recruitment and mean 2023–2025 selectivity, and the deterministic fishery-weight schedule. Biology is fixed. The terminal posterior median is 14.5333%, with interval 11.2075–18.3700%.
Observed indices and Model 26.0 fitted predictions. Black points show source observations, lines show fitted predictions, and bars show approximate 95% observation-error ranges. BTS uses its covariance. The ATS age-1 panel uses a logarithmic scale in billions of fish; the retained 2020 age-1 placeholder is distinguished from the real 2020 USV biomass observation.
Figure 38: Observed indices and Model 26.0 fitted predictions. Black points show observations, lines show fitted predictions, and bars show approximate 95% observation-error ranges. BTS observation errors include covariance among survey years. The ATS age-1 panel uses a logarithmic scale in billions of fish; the 2020 age-1 placeholder is distinguished from the real 2020 USV biomass observation.
Model 26.0 index residuals relative to the selected observation errors, with BTS accounting for covariance among survey years. Dashed lines mark the standard-normal 95% reference range. The retained 2020 ATS age-1 placeholder is distinguished and excluded from observed-index summaries; the 2020 USV biomass remains an observation.
Figure 39: Model 26.0 index residuals relative to the selected observation errors, with BTS accounting for covariance among survey years. Dashed lines mark the standard-normal 95% reference range. The 2020 ATS age-1 placeholder is distinguished and excluded from observed-index summaries; the 2020 USV biomass remains an observation.
Annual fishery selectivity at ages 1–15+ from the Model 26.0 fit. Each ridge shows the estimated age pattern for that year, using the normalization in the verified figure data.
Figure 40: Annual fishery selectivity at ages 1–15+ from Model 26.0. Each ridge shows the estimated age pattern for that year.
Annual BTS selectivity ridges for 1982–2026 in a display twice as tall as wide. Annual age-pattern values are unchanged; curves are normalized to their annual maxima.
Figure 41: Annual bottom-trawl survey selectivity at ages 1–15+ from Model 26.0. Each ridge is divided by its maximum over the displayed ages. Model curves are also shown for years without age-composition samples.
Annual ATS selectivity ridges for 1994–2026 in a display twice as tall as wide. Ages 2–15+ and all annual normalized values are unchanged.
Figure 42: Annual acoustic-trawl survey selectivity at ages 2–15+ from Model 26.0. ATS and AVO share the estimated curve; age 1 is excluded. Curves are also shown for years without age-composition samples.
Observed grouped mean age for ATS, BTS and fishery with Model 26.0 predictions and the Model 26.1.2 fishery prediction. Bars are the observed mean ±2 SE, where SE = sqrt(sum[p_obs × (age score − observed mean)^2] / N), using the selected observed proportions and likelihood input N. Ages 1–14 and 15+ are scored 1–15; ATS excludes structural age 1 and the retained 2020 substitute. The same fishery observations appear once. The alternative prediction is evaluated at its fitted conditional selectivity-state modes. Bars show uncertainty in the observations.
Figure 43: Observed grouped mean age for ATS, BTS and fishery with Model 26.0 predictions and the Model 26.1.2 fishery prediction. Bars are the observed mean ±2 SE, where SE = sqrt(sum[p_obs × (age score − observed mean)^2] / N), using the selected observed proportions and likelihood input N. Ages 1–14 and 15+ are scored 1–15; ATS excludes structural age 1 and the retained 2020 substitute. The alternative prediction is evaluated at its fitted conditional selectivity-state modes. Bars show uncertainty in the observations.
Fishery observed age proportions (cohort-colored bars) and Model 26.0 fitted proportions (points joined by lines), 1964–2008. Annual panels are arranged down columns and then across, with a common proportion scale. Each panel shows its year and selected likelihood N. Age 15+ combines older cohorts.
Figure 44: Fishery observed age proportions (cohort-colored bars) and Model 26.0 fitted proportions (points joined by lines), 1964–2008. Annual panels are arranged down columns and then across, with a common proportion scale. Each panel shows its year and likelihood sample size N. Age 15+ combines older cohorts.
Fishery observed age proportions (cohort-colored bars) and Model 26.0 fitted proportions (points joined by lines), 2009–2025. The proportion scale and cohort colors match the earlier-year figure. Each panel shows its year and selected likelihood N; age 15+ combines older cohorts.
Figure 45: Fishery observed age proportions (cohort-colored bars) and Model 26.0 fitted proportions (points joined by lines), 2009–2025. The proportion scale and cohort colors match the earlier-year figure. Each panel shows its year and likelihood sample size N; age 15+ combines older cohorts.
Bottom-trawl survey observed age proportions and Model 26.0 fitted proportions, 1982–2026. Annual panels share a proportion scale; the 2020 panel is explicitly labeled No survey. Sampled panels retain the selected likelihood Ns. Age 15+ combines older cohorts.
Figure 46: Bottom-trawl survey observed age proportions and Model 26.0 fitted proportions, 1982–2026. Annual panels share a proportion scale; the 2020 panel marks the absence of a survey. Labels give likelihood sample sizes. Age 15+ combines older cohorts.
Thirty-three annual ATS panels show observed cohort-colored bars and red fitted values only in the nineteen sampled years. Fourteen blank panels explicitly mark missing age-composition data, including 2020.
Figure 47: Acoustic-trawl survey observed and Model 26.0 fitted age proportions, 1994–2026. Empty panels mark years without age-composition observations. The 2020 placeholder composition is excluded. Panels show observed proportions, fitted proportions and likelihood sample sizes on a common scale.
Standard afscOSA four-row layout with fishery, BTS and ATS columns: aggregate fits, QQ calibration with SDNR and tail statistics, OSA bubbles, and Pearson bubbles. Filled blue and open red circles distinguish residual signs; bubble area represents residual magnitude.
Figure 48: Standard afscOSA v0.0.1 diagnostics for Model 26.0, with fishery, BTS and ATS columns. Rows show aggregate observed and fitted compositions with 95% conditional observation ranges, normal-reference QQ plots with SDNR and tail summaries, OSA residual bubbles, and Pearson residual bubbles. ATS age 1 and the 2020 placeholder composition are excluded. Aggregate ranges condition on the fit; parameter and posterior predictive uncertainty are outside their scope.
Two panels show the total NLL profile and its components. Total NLL is minimized at ATS q 0.51694. Composition contributions rise at higher q, while index contributions rise toward lower q.
Figure 49: ATS catchability likelihood profile for Model 26.0. Seventeen fixed catchability values span 0.45–0.65, including the fitted value 0.51694. Panel A shows the change in total negative log likelihood; the dashed line marks 1.92. Panel B shows composition data, index data and selectivity-deviate contributions; Other pools the remaining components. All other active parameters were re-estimated at each fixed q.
Panel A shows the negative log normalized ATS-q marginal density and profile NLL, each centered at its minimum. Panel B compares dashed quadratic MCMC component curves with solid profile component curves for three terms.
Figure 50: ATS-q negative log marginal density and likelihood profile for Model 26.0. Panel A compares the negative log of the MCMC marginal density, normalized to integrate to one, with the optimized profile NLL. Each curve is measured relative to its own minimum over ATS q. The marginal density uses a kernel estimate from all 5,000 saved draws. Panel B pairs weighted quadratic regressions fitted directly to all 5,000 MCMC component values with profile NLL contributions for composition data, index data and selectivity deviates. The smoothers use individual draws and are displayed over the central 99% of sampled ATS q. MCMC curves are centered at the ATS-q marginal mode; profile components retain the profile minimum as their reference. These smoothers describe conditional mean native objective components; the negative log marginal density has no unique additive decomposition into those components. Other is omitted.
Four-by-four matrix relates ATS q, summed 2026 abundance at ages 2 through 5, age-1 abundance in 2019 representing the 2018 year class, and projected 2027 female spawning biomass. Lower panels show paired draws; upper panels show correlations; diagonal panels show marginal densities.
Figure 51: MCMC pairs plot of ATS catchability, 2026 abundance at ages 2–5, age-1 abundance in 2019 (the 2018 year class), and projected 2027 female spawning biomass for Model 26.0. Lower-triangle panels show paired values from 5,000 MCMC draws; upper-triangle panels give posterior Pearson correlations. Diagonal panels show marginal densities. Abundances are in billion fish and female SSB in million tons. The 2027 projection uses 1,375 kt catch, mean 2023–2025 fishery selectivity and within-draw mean 1978–2023 recruitment, with biological schedules fixed.
Six panels show retrospective point trajectories for female spawning biomass, age-1 recruitment and maximum fishing mortality. The right analysis refits Model 26.1.2 conditionally at fixed full-model process SDs and uses its own conditional 2026 reference.
Figure 52: Retrospective trajectories for Model 26.0 (left) and Model 26.1.2 with fixed process SDs (right). Black lines show each analysis’s matched full 2026 reference; colors identify the nine peels ending in 2017–2025, and symbols mark their endpoints. Female spawning biomass is in million tons, age-1 recruitment is in billion fish, and maximum fishing mortality across ages is per year. Recruitment is indexed by the calendar year fish enter age 1. Panels show point estimates.
Historical age-3-plus biomass trajectories from assessments issued in 2007 through 2024, compared with the Model 26.0 trajectory through 2026. Estimates decline after 2022 through 2025 and rise in 2026.
Figure 53: Historical retrospectives of beginning-of-year age-3+ EBS pollock biomass. Gray lines show archived 2007–2023 assessments; orange shows the official 2024 SAFE Table 27 estimates through 2024; blue shows Model 26.0 estimates through 2026. Biomass sums beginning-of-year numbers at ages 3–15+ multiplied by the corresponding annual fishery weights at age, using the Model 26.0 fit. Historical series use assessment-specific biomass definitions and may include next-year estimates. The 2024 tabulated values are rounded. No new assessment fit was produced in 2025. These are point estimates from successive assessments, encompassing changes in data, methods and biological inputs.
Selected annual composition sample sizes and their Francis diagnostic equivalents for the Model 26.0 fishery, BTS and ATS groups. This is a diagnostic comparison; no Francis reweighting is applied to the assessment inputs.
Figure 54: Annual age-composition sample sizes used in Model 26.0 and their Francis diagnostic equivalents for the fishery, BTS and ATS. The comparison evaluates weighting; the assessment input weights are unchanged.
Standardized mean-age residuals used in the Francis diagnostic comparison for Model 26.0, with the selected input sample sizes. Positive values indicate older observed than predicted mean age. The original selected-data treatment and diagnostic formulas are retained.
Figure 55: Standardized mean-age residuals used in the Francis diagnostic comparison for Model 26.0, with the selected input sample sizes. Positive values indicate older observed than predicted mean age.
Annual fishery selectivity from Models 26.0 and 26.1.0. The split configuration separates Foreign and Modern domestic fisheries. Curves use the normalization in the verified figure data.
Figure 56: Annual fishery selectivity from Models 26.0 and 26.1.0. The split configuration separates Foreign and Modern domestic fisheries.
Fishery selectivity before and after the fleet split, with signed 1991-minus-1990 differences by age for Models 26.0 and 26.1.0. The figure preserves the existing boundary-year and normalization definitions.
Figure 57: Fishery selectivity before and after the fleet split, with signed 1991-minus-1990 differences by age for Models 26.0 and 26.1.0.
Three diagnostic rows compared Model 26.0 with the same Foreign-period and Modern-period observations used for Model 26.1.2. The aggregate fits followed the dominant ages. Annual mean ages showed larger early discrepancies and close modern fits. Open and filled bubbles identified the direction and size of age-proportion differences.
Figure 58: Model 26.0 fishery age-composition fits, displayed separately for the Foreign (1964–1990, left) and Modern domestic (1991–2025, right) periods for comparison with Model 26.1.2. Model 26.0 fits one fishery. Row A compares sample-weighted observed age proportions (bars) with fitted proportions (black lines). Row B compares observed annual mean ages and approximate 95% sampling intervals with fitted mean ages. Row C shows observed minus fitted proportions in percentage points: open red circles indicate observations above the fit, and filled blue circles indicate observations below it. Bubble area shows the difference magnitude on the same scale as the Model 26.1.2 figure. Mean ages treat 15+ as age 15.
Three diagnostic rows compared Model 26.1.2 with Foreign and Modern domestic observations. The Modern mean-age and age-proportion fits improved relative to Model 26.0, while larger discrepancies persisted in the Foreign period. Open and filled bubbles distinguished observed proportions above and below fitted values.
Figure 59: Model 26.1.2 fishery age-composition fits from the conditional fit with fixed process SDs. Columns show the Foreign and Modern domestic fisheries. Row A compares sample-weighted observed and fitted age proportions; row B compares observed annual mean ages and approximate 95% sampling intervals with fitted mean ages; row C shows observed minus fitted proportions in percentage points. Observations, likelihood weights, age ranges and bubble scale match the Model 26.0 figure. Mean-age intervals describe observation sampling uncertainty; fitted curves are point estimates. Mean ages treat 15+ as age 15.
Four panels compare nine same-year terminal revisions from ten fixed-fit and ten posterior-draw simulated datasets with the observed Model 26.0 revisions, for spawning biomass and age-1 recruitment.
Figure 60: Conditional simulation-retrospective revisions for Model 26.0. Columns show ten datasets generated at the fitted parameters (left) and ten generated from regularized posterior parameter draws (right). Rows show female spawning biomass and age-1 recruitment. Blue points identify individual simulated datasets, blue lines join their medians, and black diamonds and lines show observed-data revisions. For a peel ending in year y, revision is 100 × [peel estimate in year y / its own full 2026 fit estimate for year y − 1]. Both columns use the same vertical scale within a quantity.
Six by six native SparseNUTS matrix for Fishery log F 1965, CPUE log q, Fishery log F 1964, Fishery log F 1966, Fishery log F 1967, Fishery log F 1970 . Lower panels show retained posterior points with red regularized MAP points and matching local Normal ellipses. Diagonals show four chain traces and convergence annotations; upper panels report pooled correlations.
Figure 61: Native SparseNUTS pairs diagnostic for the six parameters with the lowest bulk effective sample size in the newly fitted regularized Model 26.0 posterior. Lower panels show all 5,000 retained draws in black, the saved regularized native MAP as a red dot, and the 95% bivariate Normal approximation from the matching full inverse augmented Hessian as a red ellipse. Upper panels report pooled posterior Pearson correlations. Diagonal panels show four retained chain traces, bulk ESS and R-hat. Parameters retain their native coordinate scales. Local ranges are calculated at the regularized MAP, distinct from the production penalized-ML fit.
A logarithmic scatterplot compares local Hessian SE with posterior SD on matching parameter scales. The six slowest parameters are ringed, and the diagonal marks equality.
Figure 62: Local Hessian SE and posterior SD on the same parameter scale for all 1,266 active parameters under the same regularized target. Both axes use logarithmic scales; the dashed line denotes equality. Rings identify the six slowest parameters, with posterior-SD/local-SE ratios 1.28–1.52. Coordinate units differ among parameters. MCMC standard errors quantify simulation precision and are separate from the parameter uncertainties shown here.
Six histograms show marginal posterior distributions. Panels use parameter units. The panels show the final reported MCMC marginals.
Figure 63: MCMC posterior histograms for the six parameters with the lowest bulk ESS in the original chains. All 5,000 parameter vectors contribute. Bar heights show probability per bin; the panels retain parameter units.
Five panels compare observed indices with median model expectations and the middle 95 percent of simulated observations. Simulation includes parameter uncertainty and the assumed observation errors; biological inputs are fixed.
Figure 64: Index checks compare observed survey and historical catch-rate indices with simulated observations generated from 1,000 MCMC draws. Each draw supplies a model expectation; random observation errors are then added using the same error assumptions used to fit each index, including the relationships among BTS errors. Lines show median expectations and shading covers the middle 95% of simulated observations at each year. Circles are observed indices and triangles identify existing substitutes. Some simulated values are negative because the fitted Normal error distributions allow them. The BTS overall mismatch measure exceeds its observed value in 0.2% of simulations, indicating that the model rarely reproduces this feature of the BTS data. Biological inputs remain fixed.
Nine panels compare observed age proportions with median model proportions and the middle 95 percent of simulated sample proportions. Samples use model age proportions and rounded fitting sample sizes. Age 15 includes older fish.
Figure 65: Age-composition checks compare the latest three observed samples from each data source with simulated samples generated from 1,000 MCMC draws. For each draw, fish are randomly assigned to age groups using the model-predicted age proportions and the sample size used in fitting, rounded to a whole number. Lines show median model proportions, shading covers the middle 95% of simulated sample proportions at each age, and points show observed proportions. The shading includes parameter uncertainty and the assumed sampling variation. This simulation approximates the age-composition fitting formula, which adds a small constant to age proportions when calculating fit. The 2020 ATS substitute is excluded. Age 15 includes all older fish. Age conversions, weights and other biology remain fixed.
Two panels show projected catch with 5th–95th percentile ribbons, ten matched colored future-recruitment trajectories and black simulation means. Catch paths coincide in Alternative 2 during the prescribed 2027 and 2028 catches, then spread with recruitment variation.
Figure 66: Catch projections for Model 26.0 under Alternative 2 (expected catch, top) and Alternative 3 (recent mean F, bottom). Black lines show simulation means, ribbons show the 5th–95th percentiles from 1,000 future-recruitment simulations, and thin colored lines show ten matched trajectories. Colors identify the same recruitment realization in both alternatives and the spawning-biomass figure. Alternative 2 fixes catch at 1,375 kt in 2027 and 2028, then applies the maximum-ABC rule; its paths coincide in the prescribed-catch years. The ribbons represent future recruitment variation; the advice tables retain historical-mean recruitment.
Two panels show female spawning biomass under Alternatives 2 and 3 with uncertainty ribbons, ten matched colored trajectories, black simulation means and horizontal B40-percent and B35-percent reference lines. The spread increases as simulated recruitment contributes to spawning biomass.
Figure 67: Female spawning-biomass projections for Model 26.0 under Alternative 2 (top) and Alternative 3 (bottom). Black lines show simulation means, ribbons show the 5th–95th percentiles from 1,000 future-recruitment simulations, and thin colored lines show the same ten matched trajectories as the catch figure. Future recruitment follows an inverse-Gaussian distribution fitted to the 1978–2023 age-1 entries. These ranges include future recruitment variation only. Dashed B40% and dotted B35% lines mark the primary projection reference points.
Year-labelled trajectory of biomass relative to B35 percent and fishing mortality relative to F35 percent. The final fitted year and both projections lie above B35 percent and below F35 percent. Boxed 27 and 28 labels distinguish projected years. Historical ratios use the same current reference points throughout.
Figure 68: Historical trajectory of Model 26.0 female spawning biomass (B) and maximum fishing mortality at age (F), 1981–2026, with deterministic Alternative 2 projections for 2027–2028. Ratios use the current primary Tier 3 reference points, B35% = 2.155 million t and F35% = 0.658 per year, held constant across years. Lines connect consecutive years; two-digit labels identify years, and boxed labels with yellow shading identify projections. Solid lines mark ratios of one; the dashed vertical line marks half B35%. Projected catch is 1.375 million t in each year.
Recent normalized fishery selectivity curves from the Model 26.0 and the proposed raw-curve averaging reference. Half-maximum crossings and curve-shape summaries use the existing verified definitions.
Figure 69: Recent normalized Model 26.0 fishery selectivity curves and the proposed reference based on averaging the unnormalized curves.
Annual Model 26.0 fishery selectivity curves for 2007–2026, each compared with the proposed 2023–2025 raw-curve average rescaled to maximum one. The inferred 2026 curve retains its distinction from directly informed earlier-year curves.
Figure 70: Annual Model 26.0 fishery selectivity curves for 2007–2026, each compared with the proposed 2023–2025 raw-curve average rescaled to maximum one. The 2026 curve is estimated without 2026 fishery age compositions.
Changes in maximum ABC and OFL under the annual future-selectivity curves relative to the matching Model 26.0 baseline. Rows retain the 2027 maximum-ABC ordering. These are projection selectivity sensitivities conditional on the same fitted source and projection design.
Figure 71: Changes in maximum ABC and OFL under the annual future-selectivity curves relative to the matching Model 26.0 baseline. Rows are ordered by 2027 maximum ABC. These are projection selectivity sensitivities conditional on the same fitted source and projection design.
Annual Model 26.0 fishery selectivity and fully selected F35%, a proxy for FMSY, for 2001–2026. Mean selected age uses ages 1–10; SPR uses ages 1–14 and 15+, fixed 2026 mortality, maturity and female spawning weights, and quarter-year spawning timing. Curves are normalized to maximum one. The 2023–2025 mean-curve reference and inferred 2026 curve remain separately identified. The historical 2024 figure used FMSY, a different quantity.
Figure 73: Annual Model 26.0 fishery selectivity and fully selected F35%, a proxy for FMSY, for 2001–2026. Mean selected age uses ages 1–10; SPR uses ages 1–14 and 15+, fixed mortality, maturity and the selected projection spawning weights, and quarter-year spawning timing. Curves are normalized to maximum one. The 2024 figure plotted FMSY.

Appendices

Appendix A
SSC and Plan Team Requests and Responses

The Plan Team requests and assessment responses are summarized in Table A1.

Table A1 Responses to SSC and Plan Team Requests
SSC and Plan Team requests
ID Recommendation Response Response status
PT-01 Bring Model 26.0 forward for management use in November and present Model 23.0 for continuity and comparison during the transition to Rceattle. Model 26.0 estimates, uncertainty, diagnostics, Tier 3 projections and Model 23.0 comparisons are presented. Regularized posterior summaries, predictive checks and observed and simulated-data retrospectives are included. Model 26.1.2 is a sensitivity comparison conditional on fixed Foreign and Modern process SDs of 0.1235 and 0.582. Risk categories are Level 1. Assessment results and sensitivity comparisons presented
PT-02 Evaluate alternative treatments of age-1 BTS selectivity, including the selectivity penalty and a time-invariant alternative, to assess their influence on the retrospective pattern. The author proposes no additional age-1 BTS selectivity sensitivities for this assessment. Observed and simulated-data retrospective results are presented; these results do not separately identify the effect of an alternative age-1 selectivity treatment. No additional age-1 selectivity tests proposed
PT-03 Extend the Model 26.0 self-test with retrospective peels on simulated datasets generated from the fitted model, and examine retrospective patterns in time-varying selectivity estimates. Two sets of ten simulated datasets use the fitted parameters and ten regularized posterior draws, respectively. Each dataset has a full-2026 fit and nine peels ending in 2017–2025. Observed spawning-biomass rho (+0.121) exceeds every simulated value in both sets. Posterior diagnostics and predictive checks are also presented. The simulations assess population revisions; they establish no single retrospective cause. Paired simulation retrospectives and posterior predictive checks presented
PT-04 Present retrospective results from Models 23.0 and 26.0 side by side in November. Matched retrospective runs for Models 23.0 and 26.0 were completed and compared side by side. Both showed similar spawning-biomass retrospective patterns, with nine-peel Mohn’s rho of +0.156 and +0.143, respectively (positive values indicate higher estimates in the shorter fits). See the side-by-side comparison and numerical summaries. Completed; requested comparison provided
PT-05 Further examine the influence of BTS index volatility and other potential data or ecosystem-related causes on the retrospective pattern. The author proposes no additional BTS data-influence tests for this assessment. Model and cumulative-data comparisons, observed and simulated-data retrospectives, and posterior predictive checks are presented. The BTS mismatch measure is as large as observed in 0.2% of predictive simulations. These results identify model-data mismatch but establish no ecosystem cause. Diagnostics presented; no additional BTS influence tests proposed
PT-06 Clearly document age-composition weighting in Model 26.0 and prioritize further evaluation of data weighting given patterns in the OSA diagnostics. Age-composition information weights and likelihood multipliers are documented by data source and year. Model 26.0 and fixed-SD conditional Model 26.1.2 OSA and mean-age comparisons retain the selected sample sizes. Model 26.1.2 residuals condition on fitted selectivity states and exclude parameter uncertainty. Diagnostic equivalent weights are not applied as new inputs. Alternative-weight fits are outside the scope of this comparison. Weighting and conditional diagnostics presented; alternative-weight fits remain separate
PT-07 Continue development of material that could contribute to a future EBS pollock Ecosystem and Socioeconomic Profile, as resources allow. A draft was developed in September and further work is included here following recommended format and guidance. Draft has been developed and is included as Appendix B.

Note. Responses to the September 2026 BSAI Groundfish Plan Team recommendations. Status distinguishes completed work, decisions about further tests and development of the ESP draft.

Earlier SSC comments and response plan

The matrix below preserves the October 2025 SSC response plan as reproduced in the September 2026 development source. It records proposed actions at that stage; completion and outstanding work are identified in Section 1.4 and the response registers. Its RTMB and Model 25.0 entries are historical planning context rather than the software selection. The September 2026 Plan Team direction establishes Model 26.0 and Model 23.0 as the November main and comparison models; the RTMB and SPoRC work remains part of the development record.

The earlier SSC comments and response plan are reproduced in Table A2.

SSC comment Response
Use the 2024 base model as the source for an RTMB implementation, with routine data updates. Use the accepted Model 23.0 (ADMB) configuration as the scientific source. First check the direct RTMB translation as Model 23.1, then use Model 25.0 (RTMB) for the assessment line begun in 2025. List each new data set and each model change separately. Save the model version, run files, diagnostics, projections, and management quantities used in the report.
Use the updated Groundfish Assessment Program estimates of survey biomass and age composition. Add the sdmTMB biomass estimates and tinyVAST age compositions as revised survey data. Record when the estimates were received, the software version, model settings, and input files. Compare the old and new survey series and show whether the change affects the assessment results.
Use FT-NIRS age compositions for the 2025 fishery and surveys. Document how the FT-NIRS ages were produced, screened, grouped, and assigned to fishery and survey data. Record sample sizes and aging-error matrices. Check the final model input against the source data before fitting the assessment.
Compare traditional microscope ages with FT-NIRS ages and show the effects on model results and management quantities. Run the same assessment with traditional ages, FT-NIRS ages with one aging-error matrix, and FT-NIRS ages with fleet-specific aging-error matrices. Compare cohort patterns, fits to fishery and survey ages, residuals, recruitment, spawning biomass, reference points, ABC, and OFL. Save the full comparison in the assessment appendix and at a permanent web address.
Revisit the revised AVO index after the new uncertainty analysis has been reviewed. After review of the final uncertainty method, compare the revised point estimates and uncertainty with the AVO series. Show their effect on model fit, stock estimates, and management quantities before proposing a change to the base model.
Develop a plan with the BSAI Groundfish Plan Team for moving beyond ADMB. Use the model history and numbering plan above. Compare RTMB, Rceattle, and SPoRC with the same data and a common set of tests. Ask the Plan Team to agree on the tests before selecting the model software for future assessments. Keep the accepted assessment model as the control until a replacement gives stable estimates, sound uncertainty, acceptable retrospective results, and reproducible projections.
Examine the effect of including Russian catches. First confirm the source, area, years, units, species identification, and uncertainty of the Russian catch estimates. Then run clearly defined catch scenarios. Explain the assumptions about stock movement and population boundaries and show the effects on stock size, reference points, ABC, and OFL.
Explore time-varying natural mortality, selectivity, age-composition weighting, and cohort and temperature effects on weight-at-age. Study each topic separately. State the scientific question before fitting a model. For each change, show model fit, parameter uncertainty, retrospective results, projections, and effects on management advice. Keep poorly estimated or unstable models as research results.
Continue work with CEATTLE estimates of natural mortality and consider Rceattle for time-varying mortality. Test time-varying natural mortality as a sensitivity analysis. Check whether the model can separate mortality changes from recruitment, selectivity, and survey effects. The full set of assessment needs will guide the choice of model software.
Explain how the recruitment penalty affects the estimated 2018 year class and why the likelihood profile favored a larger recruitment estimate. Prepare a likelihood profile for the 2018 recruitment deviation. Show how the recruitment penalty and each data source change across the profile. Explain which parts of the model favor a larger year class and how the estimate affects spawning biomass, reference points, ABC, and OFL.
Clearly identify the models proposed for the assessment, including model numbers. Use Model 23.0 (ADMB) for the accepted 2024 source, Model 23.1 (RTMB) for the direct translation check, Model 25.0 (RTMB) for the line begun in 2025, and Model 26.0 (Rceattle) for the line begun in 2026. Use the same short names in the report, presentations, run folders, tables, and archive. For every model, list its purpose, parent model, data set, model changes, software version, and review status. State clearly which model is recommended for management advice.
Archive the October and December SAFE documents and presentations. Archive the October 2025 material that exists and add a short note explaining that the funding lapse prevented the November and December SAFE package. For future reviews, save the Quarto source, rendered reports, presentations, model files, data list, software versions, and file checksums in one dated release.

Note. Responses to the October 2025 SSC comments on EBS pollock. The SSC comments are summarized from pages 27 to 29 of the final October 2025 SSC report.

Table A2 Earlier SSC Comments and Response Plan

Appendix B
Ecosystem and Socioeconomic Profile of Eastern Bering Sea Walleye Pollock

This draft Ecosystem and Socioeconomic Profile (ESP) for EBS pollock brings together substantial work completed to date and provides a starting point for future ESP Team discussions. An AI agent helped compile and coordinate material from disparate information sources and research activities. Over the next year, the EBS pollock ESP Team will formalize its membership and begin meetings that engage a broader group of scientific experts to develop the profile. Please contact Jim Ianelli and Kalei Shotwell with questions or for further details about this document or the EBS pollock ESP.

Executive Summary

The Ecosystem and Socioeconomic Profile (ESP) connects stock-specific environmental, biological, fishery, and community information with assessment interpretation and management questions. Its sequence of focus, synthesis, analysis, and communication provides a structured way to evaluate proposed indicators (Shotwell et al. 2023). This draft focuses initially on recruitment to age 1, then identifies processes affecting juvenile survival to age 3, adult growth and condition, survey interpretation, and fishery performance.

The ESP distinguishes two DSEM applications. The archived Rceattle pilot evaluates birth-year SST and age-1-year cold-pool proxies (Ianelli et al. 2026). A separate age-1 DSEM working paper analyzes 18 ecosystem series alongside an age-1 response estimated by the assessment. Regional age-0 energy density provides an additional measured-condition series (Page and Maselko 2026).

Acceptable Biological Catch Considerations

Candidate Predictive Indicators

Fall age-0 total energy, prey quality and abundance, and juvenile–predator overlap are priorities for testing. Field studies connect fall total energy with age-1 recruits per spawner, and laboratory experiments identify body size and energy reserves as determinants of survival during food deprivation (Heintz et al. 2013; Sogard and Olla 2000). Studies of pollock recruitment and spatial predation identify juvenile overlap with adult pollock and arrowtooth flounder as another important pathway (Mueter et al. 2006; Spencer et al. 2016).

The regional energy-density series contain 21 southeastern Bering Sea (SEBS) and 15 northern Bering Sea (NBS) annual means within 2002–2025, measured in kJ/g dry mass. The latest values, for 2025, are 19.23 and 20.84 kJ/g dry mass for SEBS and NBS, respectively. Both are lower than their 2024 observations; a 2026 energy-density observation is absent. Sampling metadata, observation uncertainty, and forecast evaluation remain prerequisites for a predictive role (Page and Maselko 2026).

Contextual Indicators

Sea ice, seasonal temperature, cold-pool extent, plankton and euphausiids, age-0 abundance and condition, adult condition, weight-at-age, and predator overlap form the initial contextual set. The relevant biological question is whether each cohort encounters adequate prey, accumulates energy before winter, and survives subsequent predation. The poor 2007 cohort illustrates why a favorable temperature category alone can give an incomplete account: low summer production and poor age-0 condition occurred during a cold year (Gann et al. 2016).

The 2026 physical and prey indicators show a mixed pattern relative to their own observed-period means. Sea ice and cold-pool extent are above those means; SST and bottom temperature are below. The open-water bloom indicator is lower, while chlorophyll a is higher. Spring small and large copepods and summer small copepods are below their respective means; summer large copepods are slightly above.

Fishery Informed Indicators

Candidate indicators include age and size composition of catch, fishery weight-at-age, season and area of harvest, standardized fishery catch rates, catch and quota utilization, and salmon bycatch measures. Their interpretation must account for fishing choices, allocation and avoidance behavior, processing demand, and reporting coverage. These indicators may reveal operational changes or sampling differences that help interpret assessment inputs. Their proposed inclusion in this ESP requires a defined management question.

The draft supports evaluation of ecosystem and fishery concerns in the SAFE risk table. Any resulting change in risk classification or ABC must be documented by the assessment authors using the completed annual synthesis and assessment results. ABC and OFL remain unchanged by this contribution.

Total Allowable Catch Considerations

Verified economic context covers BSAI catch, participation, ex-vessel and first-wholesale statistics through 2024, and U.S.-national trade through 2025 (Catch and Market Context). These scopes differ from the BS assessment stock and from each other. A speculative 2026 interpretation is that firmer product unit values could support gross returns, while operating costs and product mix could offset those gains unevenly among vessels, processors and communities. 2026 margins and community outcomes remain uncertain. This interpretation is qualitative.

Responses to SSC and Plan Team Comments on ESPs in General

A summary of potential SSC/PT comments on ESPs in general includes: distinguish predictive from contextual indicators, evaluate competing mechanistic explanations, document DSEM diagnostics, and coordinate economic and community information with existing Council products. This pollock contribution addresses those questions by defining indicator roles, documenting the fitted pilot and its diagnostic limitation, and proposing an explicit socioeconomic inventory.

Responses to SSC and Plan Team Comments Specific to EBS Pollock

December 2024 SSC, EBS Ecosystem Status Report (page 3): the SSC recommended pollock-focused DSEM work to reconcile contrasting larval, juvenile-condition, and adult signals, and to investigate changed recruitment relationships (North Pacific Fishery Management Council Scientific and Statistical Committee 2024).

Contribution to that work: The starter age-1 DSEM analysis appears in the 2026 EBS Ecosystem Status Report (Siddon 2026).

The assessment website records continuing work on contrasting early-life observations, cannibalism and biomass consumed, multispecies mortality, weight-at-age and condition, and stock distribution across U.S. and Russian waters (EBS Pollock Assessment Team 2026). Its retained earlier responses carry an explicit requirement for verification before use as final results. This draft translates those topics into proposed ESP tasks.

Pollock review topics and proposed ESP contributions are summarized in Table B1.

Introduction

Pollock recruitment reflects survival through several life stages with different food requirements, habitats, and predator exposure. Large differences in egg or larval abundance can be modified by later feeding, growth, transport, and mortality. The first-year review by Duffy-Anderson et al. provides the organizing synthesis for these processes (Duffy-Anderson et al. 2016). The local recruitment review extends that structure through ages 1 and 2 to survival at age 3. In this appendix, age-1 recruitment is the focal response used by the DSEM pilot; survival to age 3 is a separate later-stage outcome that retains the identity of the same birth cohort.

Justification

The ESP creates an evidence trail from a biological or socioeconomic question to an indicator and its proposed use. For EBS pollock, the immediate question is whether early-life information can improve interpretation of uncertain recruitment and future biomass. Additional questions concern adult productivity, changing spatial availability to surveys, fishery operations, and community exposure. The September 2026 document provides the starting framework for developing this appendix (Ianelli et al. 2026).

Data

Age-0 Energy Density

Annual mean energy density of age-0 walleye pollock is available for the northern and southeastern Bering Sea during 2002–2025, in kJ/g dry mass (Page and Maselko 2026). Johanna Page (Vollenweider) provided the data, with Jacek Maselko as a co-contact. The southeastern series contains 21 annual means and the northern series contains 15. Both regions lack observations for 2003, 2013 and 2020; the northern series also lacks 2008–2012 and 2014.

The source inventory and remaining data-assembly needs are summarized in Table B2.

Indicator Synthesis

Ecosystem Processes

Spawning Supply and Transport

Spawning biomass and spawning location influence egg and early-larval supply. Smart et al. found associations between spawning biomass and early stages, with weaker correspondence after early larval development (Smart et al. 2012). Transport and the spatial arrangement of spawning also matter. The biophysical model of Petrik et al. reproduced warm–cold distribution differences most successfully through changes in spawning areas (Petrik et al. 2015). These results support separate hypotheses for cohort supply, transport, and access to nursery habitat.

Feeding and Fall Age-0 Condition

Prey availability includes amount, nutritional quality, and spatial match with fish. Larval copepod concentrations and frontal habitat illustrate why a broad regional biomass index can differ from prey encountered by an individual fish (Smart et al. 2012; Brodeur et al. 2000). Diet studies show that prey use varies with fish size and that pollock and Pacific cod can partition prey (Buckley et al. 2016; Strasburger et al. 2014).

Siddon et al. describe a seasonal shift from larval growth and development toward lipid storage after transformation to the juvenile stage (Siddon et al. 2013). Heintz et al. found higher diet lipid content and age-0 energy density during cold conditions in their study; fall total energy was positively associated with age-1 recruits per spawner (Heintz et al. 2013). Moss et al. also documented differences in age-0 energetic condition and food habits across thermal conditions (Moss et al. 2009). These findings motivate indicators of energy density, body mass, and total energy with explicit measurement definitions. The annual series measures energy density in kJ/g dry mass.

Eisner et al. evaluated large copepods as leading indicators of age-3 pollock abundance for the 2002–2015 year classes, excluding 2013 (Eisner et al. 2020). Their comparison reinforces the value of prey information while identifying a specific cohort range and recruitment age.

Overwinter Survival

Fall condition provides the starting reserves for the first winter. Sogard and Olla’s food-deprivation experiments show that greater size, higher initial condition, and colder water can extend survival (Sogard and Olla 2000). Field survival also involves winter feeding, movement, and predators. Laboratory results therefore support a mechanism and its direction, while annual field data are needed to quantify its effect on recruitment.

Sea ice, bloom timing, summer mixing, and temperature influence prey production and energy demand. Sigler et al. connect annual production of copepods, euphausiids, and juvenile pollock with seasonal environmental conditions (Sigler et al. 2016). Gann et al.’s analysis of 2007 identifies a plausible production limitation during a cold year (Gann et al. 2016). The ESP should evaluate these intermediate processes before interpreting a simple warm–cold contrast as a cohort forecast.

Predation and Later Juvenile Survival

Adult pollock can increase juvenile mortality through cannibalism, while arrowtooth flounder and other predators create additional exposure. Mueter et al. identify both food-related and predation-related controls on pollock recruitment, including juvenile–adult overlap (Mueter et al. 2006). Spencer et al. model spatial predation by arrowtooth flounder and show how cold-pool extent can alter predator access to juvenile habitat (Spencer et al. 2016).

The timing of predation matters for the response. A summer overlap or cold-pool observation in year t+1t+1 occurs after the beginning of the cohort’s age-1 year. Its use to explain an age-1 entry state requires explicit justification or a revised response definition. Such observations may be more directly aligned with survival during age 1 and later ages.

Life stages, processes and priority observations are summarized in Table B3.

Workshop Conceptual Models for Recruitment and Growth

The January 2025 pollock biology and ecology workshop developed preliminary conceptual models for Bering Sea recruitment and growth (Monnahan et al. 2026). Figure B1 organizes reproductive output, seasonal juvenile stages, prey quality, energetic condition, predation, and cold-pool extent. Figure B2 connects population weight-at-age with somatic growth, size-selective mortality, prey, competitors, fishing, and physical conditions. Together they support an ESP that examines recruitment and growth.

Recruitment pathways: spawning biomass and fecundity inform reproductive output. Seasonal surveys track the cohort from spring age 0 through age 2. Diet, krill, copepods, and prey lipid measurements inform forage quality and juvenile energetic condition; predation indices and cold-pool extent inform later survival. The diagram highlights both candidate observations and intermediate biological states.

Growth pathways: the model separates growth of surviving fish from changes in population weight-at-age associated with size-selective mortality. Prey availability, density, genetic diversity, and spatial history enter the growth network alongside physical conditions and zooplankton. This distinction supports age- and season-specific weight and condition indicators with explicit survey or fishery sampling definitions.

The cohort sequence in Figure B3 summarizes the recruitment mechanisms developed in this draft and extends the survival question to age 3. The workshop diagrams provide a broader set of hypotheses for future indicator development.

Socioeconomic Processes

Biological supply, access to fishing grounds, operating costs, product demand, and processing capacity can jointly affect realized harvest and its value. Those processes may alter where and when vessels fish, the size and age of fish landed, and the distribution of benefits. This component should therefore connect each indicator to a concrete question, such as whether lower quota utilization reflects reduced fish availability, market conditions, processing limits, or avoidance behavior.

The Economic SAFE provides source categories for catch, discards, prohibited species catch, production and value, participation, and effort (Alaska Fisheries Science Center 2026b). This draft proposes species- and sector-specific summaries where the source supports that detail. Community analysis requires clear distinctions among landing ports, vessel ownership, workforce residence, processor location, and CDQ beneficiaries. Each describes a different form of participation or exposure.

Proposed Indicators

The mechanism table (Table B4) links a driver, a measurable process, and the intended response. Expected directions are hypotheses for the stated pathway. Several upstream physical effects depend on season, prey response, and spatial coverage, so their net sign can change across conditions.

Indicator Assessment

Indicator Selection

Selection starts with a mechanistic explanation, the population or socioeconomic response, and the date when the information becomes available. Candidates then require reliable annual production, adequate spatial and temporal coverage, quantified uncertainty, and additional information beyond the other indicators.

Ecosystem Indicators

The initial set should remain small enough for scientific review: seasonal physical forcing; a documented prey index; fall age-0 size and energetic condition; juvenile–predator overlap or a reviewed mortality product; and adult growth and condition. Larval supply and transport add value when annual coverage and biological alignment support them. Indicator families should be assessed together so correlated temperature, ice, and prey signals receive an interpretation that accounts for shared processes.

The available age-0 energy-density series describe regional energetic condition (Figure B4). The histories of the ecosystem inputs and age-1 response provide context for the DSEM analysis (Figure B5).

Socioeconomic Indicators

Proposed socioeconomic indicator families, measures and management questions are summarized in Table B5.

Catch and Market Context

The broader Bering Sea and Aleutian Islands (BSAI) pollock fishery reported 1.3163 million tons of total catch in 2024 (Table B6). Trawl catcher vessels retained 678.40 thousand tons, with an ex-vessel value of $213.43 million. These economic statistics cover the BSAI; their area and accounting definitions differ from the BS stock-assessment catch series. Published pollock-target vessel counts were 103 across harvesting sectors and 76 catcher vessels. The counts describe participation in the target fishery and include their source-specific gear definitions.

Published first-wholesale pollock production was 487.89 thousand tons of product weight and $1.4743 billion in 2024 (Table B7). The Economic SAFE excludes confidential components from some aggregates; the combined fillet quantities and derived values for 2021–2022 remain unavailable here. Product mix and market conditions both affect the observed unit values (Abelman et al. 2026).

Global Alaska pollock capture production was 3.573 million tons in 2024 (Table B8, panel A). The United States and Russian Federation accounted for 39.9% and 54.0%, respectively, and BSAI catch represented about 36.8% of the global total. U.S. Alaska-pollock domestic exports totaled 333 thousand tons of products valued at $1.00 billion in 2025, compared with 332 thousand tons and $0.946 billion in 2024 (panel B). These national trade statistics extend through 2025; global catch statistics extend through 2024. Their product weights, nominal export values and legacy import/destination baskets are defined in the table notes (FAO 2026; NOAA Fisheries 2026).

Among the three destination groups shown, selected European countries accounted for the largest export shares throughout 2020–2025 (Figure B6). Meat’s share of export volume rose from 45.8% in 2020 to 53.3% in 2025, while its value share rose from 44.0% to 53.0% (Figure B7). The Russian Federation accounted for more than half of global catch in each year from 2020 to 2024 (Figure B8). First-wholesale surimi volume declined from 185.5 to 165.1 thousand tons between 2023 and 2024, while fillet volume rose from 142.9 to 158.6 thousand tons (Figure B9).

Annual Indicator Status

Age-0 Energy Density Through 2025

The latest five available observation years are 2021–2025 (Table B9). In 2025, the SEBS annual mean was 19.23 kJ/g dry mass, 0.64 lower than in 2024. The NBS annual mean was 20.84, 0.09 lower than in 2024 (Page and Maselko 2026). These are descriptive differences between annual means.

Annual Indicator Series

The age-1 DSEM input spans 1964–2026 and contains 18 ecosystem series plus the assessment-derived age-1 response (Figure B5). Seventeen ecosystem series have 2026 values; the energy-density series ends in 2025, and age-1 observations end in 2024.

Standardized departures below equal each value minus that series’ mean, divided by its sample standard deviation. Each baseline uses all available finite observations, including the latest year, and retains the series’ gaps. These baselines are descriptive historical variability, rather than a common fixed climatology, sampling-error intervals or approved biological thresholds.

In 2026, sea ice is +0.89 SD relative to its 1985–2026 baseline of 42 observations. Cold-pool extent is +1.12 SD, SST −0.39 SD and bottom temperature −0.79 SD relative to their separate 1982–2026 baselines of 44 available observations each. Sea ice and cold pool both exceed their 2025 values. SST also increased from 2025 despite remaining below its observed-period mean, whereas bottom temperature fell.

The open-water bloom indicator is −1.54 SD and chlorophyll a is +0.77 SD relative to their separate 1998–2026 baselines of 29 observations each. Both declined from their 2025 values. Spring small and large copepods are −0.45 and −0.66 SD using their separate 2000–2026 baselines of 25 observations; summer small and large copepods are −0.92 and +0.21 SD using their separate 2003–2026 baselines of 22 observations. The mixed physical and prey pattern supports contextual discussion rather than an overall favorable or adverse recruitment classification.

Indicator Analysis

The September 2026 assessment development document presents a pilot DSEM analysis of SST and cold-pool pathways (Ianelli et al. 2026). Tables B10–B11 reproduce its fit comparisons and direct proxy coefficients as an example of analyses that could be provided in the ESP.

Decision Support

A contextual indicator may inform the SAFE risk-table discussion when it identifies a documented condition relevant to recruitment, productivity, survey interpretation, or fishery operations. Its influence on a risk category requires an explanation of the evidence and uncertainty. A predictive indicator needs forecast evaluation and numerical checks. Incorporation into an assessment likelihood, projections, or a harvest rule requires a separate, reviewed implementation and evaluation of effects on biomass, uncertainty, ABC, and OFL.

Socioeconomic Monitoring

Socioeconomic monitoring can build on the main assessment’s discussion of fishery conditions, including fishing locations, catch rates, effort, size composition, and bycatch avoidance, alongside economic performance, participation, and community exposure. The catch-decision indicators and probabilities in Tables 55 and 56 provide a framework for comparing alternative catches in terms of fishing mortality, future spawning biomass, age composition, and relative fishing pressure. The fishing-mortality-based effort proxy describes relative pressure; observed vessel effort, catchability, operating costs, and revenues would provide the economic context for interpreting it. Future ESP drafts will pursue incorporating these fishery-condition observations and decision-table comparisons to connect projected stock outcomes with operational and socioeconomic consequences.

Data Gaps and Future Research Priorities

Ecosystem Priorities

One of our priorities is cohort-aligned predator overlap or mortality, with timing that matches the survival interval. Joint juvenile and predator distributions, diet and consumption estimates, and direct fall–spring cohort comparisons would strengthen interpretation.

Transport and nursery delivery, prey timing and lipid content, winter exposure, and annual observation-error estimates remain additional priorities. Climate relationships should be assessed for stability across recent warm conditions and historical regimes. Long-term climate projections in Mueter et al. and Spencer et al. describe conditional scenarios (Mueter et al. 2011; Spencer et al. 2016); their projected effects provide research context rather than annual 2026 indicator values.

Socioeconomic Priorities

Confirm a compact pollock-specific indicator set with economic and social science contributors. Resolve sector and community definitions, annual update capacity, disclosure rules, cost comparability, and a common price base. Evaluate whether incomplete quota utilization or altered fishing patterns have identifiable operational, market, processing, or biological causes. Document the availability date for each product so the ESP distinguishes information usable during the specification process from information released later.

Completion Priorities for the 2026 Appendix

Confirm the primary sources, units, seasonal and spatial definitions and observation uncertainty for the working annual series. Review the age-1 DAG and the proposed energy and predator pathways with the ESP and ecosystem teams. Preserve separate timing and scaling for the archived Rceattle pilot and standalone DSEM, and retain the AR1 forecast benchmark when evaluating any expanded model. Reconcile the historical pilot archive and its outstanding numerical checks before using the indicators to support an annual status or risk classification.

Conclusion

The literature supports following cohorts through spawning and delivery, prey and fall age-0 energy, first-winter survival, and later predator exposure. The ESP also considers adult productivity, survey availability and socioeconomic conditions. The regional energy-density series supplies a measured-condition indicator through 2025.

Economic observations extend through 2024 for the BSAI fishery and 2025 for national trade; the 2026 interpretation is qualitative.

Literature Cited

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Tables

Table B1 Pollock Review Topics and Proposed ESP Contributions

Review topic

Contribution in this draft

Completion needed

Contrasting larval, age-0 and adult signals

Follow cohorts through prey, condition and survival stages.

Verify source years, survey domains and cohort identity.

Cannibalism and biomass consumed

Distinguish overlap, diet occurrence, consumption and mortality.

Add reviewed consumption estimates with uncertainty.

Multispecies mortality

Treat age-specific predation as a candidate indicator.

Identify model version, predator coverage and sensitivity.

Weight-at-age and condition

Include growth and energetic context by age and season.

Update survey and fishery products and assess comparability.

U.S.–Russian distribution

Track survey domain and movement assumptions.

Use verified spatial products and explicit stock boundaries.

Note. Pollock review topics and proposed ESP contributions. Topics are paraphrased from the assessment website; final responses require the original review record.

Table B2 Source Inventory for the EBS Pollock ESP

Data group

Source and definition

Status in this contribution

Assessment states and survey inputs

EBS assessment; BTS, ATS and AVO products with age, season and spatial coverage.

Historical development material verified; align with the final 2026 SAFE run.

Temperature and cold pool

Seasonal SST; survey-derived cold-pool extent and temperatures.

Historical standardized pilot inputs archived; 2026 indicator update pending.

Prey and age-0 fish

BASIS/EcoFOCI and associated studies; size, biomass, diet and energetic measurements.

Literature reviewed; consolidate prey, size and sampling uncertainty.

Age-0 energy density

Page and Maselko annual NBS and SEBS means; 2002–2025; kJ/g dry mass.

Regional series received; season, weighting, uncertainty and cohort alignment require confirmation.

Predation

Diet observations, overlap products and multispecies model estimates.

Mechanisms synthesized; reviewed annual products required.

Catch and fishery behavior

Catch accounting, observer and fishery products; consistent season and area definitions.

Indicator specification proposed; extraction and quality review pending.

Economics and communities

Economic SAFE and approved species-level economic and community products.

Inventory proposed; latest complete years and disclosure rules require confirmation.

Note. Source inventory for the EBS pollock contribution. Availability describes this draft’s verified inputs and proposed data assembly.

Table B3 Life-Stage Synthesis for Eastern Bering Sea Pollock

Stage and timing

Processes and evidence

Priority observations

Spawning and eggs, t

Spawner output, location and transport establish early supply.

Maturity, spawning timing, egg abundance and distribution.

Larvae, t

Prey encounter, growth and delivery to nursery habitat modify supply.

Local prey, larval size and growth, transport and habitat match.

Age 0, summer–fall t

Size and lipid storage determine energy available before winter.

Mass, energy density, total energy, diet quality and prey biomass.

First winter, t to t+1

Reserves, demand, feeding and predation determine early survival.

Fall–spring cohort comparison and winter exposure.

Ages 1–2, t+1 to t+2

Spatial overlap, cannibalism and other predation affect later survival.

Juvenile and predator distributions, diets and mortality.

Adults, later years

Growth, maturity, condition and distribution affect productivity and observation.

Weight-at-age, condition, maturity and comparable spatial indices.

Note. Life-stage synthesis for eastern Bering Sea pollock. The same cohort is followed from birth year t to ages 1 and 3.

Table B4 Proposed Mechanisms and Responses

Driver and mechanism

Expected relation and timing

Evidence and candidate measurement

Spawner output → early supply

Positive toward egg supply in birth year t; later survival modifies the effect.

Smart et al. 2012; SSB, eggs and spawning location.

Prey quality and match → fall energy

Positive toward age-0 energy in t.

Heintz 2013; Siddon 2013; prey lipid, biomass and fish–prey match.

Fall size and energy → winter survival

Positive toward age-1 survival in t+1.

Heintz 2013; Sogard and Olla 2000; mass, energy density and total energy.

Summer mixing → production and prey

Conditional through nutrient supply and prey production in t.

Gann 2016; wind mixing, stratification and nutrients.

Spawning and transport → habitat match

Spatially dependent effect before and during age 0.

Petrik 2015; Smart 2012; transport and nursery-delivery indices.

Predator overlap → juvenile mortality

Negative toward subsequent cohort survival in t+1 and t+2.

Mueter 2006; Spencer 2016; overlap, diet and mortality.

Cold pool → predator access

Hypothesized benefit through separation; depends on predator and stage.

Spencer 2016; common-domain cold pool and overlap.

Late-summer SST → energetic conditions

Hypothesized negative relation with age-1 recruitment after birth-year exposure.

Mueter 2011 and pilot; seasonal SST is a broad proxy.

Note. Proposed mechanism table. Direction refers to the stated response; evidence supports hypotheses rather than a universal coefficient.

Table B5 Proposed Pollock Socioeconomic Indicators

Indicator family

Proposed measure

Management question

Participation

Active vessels, processors and deliveries by sector and season.

Where is participation changing, and which operations face exposure?

Fishery performance

Retained catch, TAC utilization and standardized effort measures.

How do fishing conditions and operating choices affect realized harvest?

Value and product mix

Ex-vessel and first-wholesale value, prices and product shares.

How do product demand and prices affect value from the catch?

Costs

Fuel, labor or other comparable cost measures where available.

What evidence indicates changes in operating margins?

Community exposure

Pollock dependence, employment and participation under approved definitions.

Which communities and CDQ beneficiaries are exposed, and through which pathways?

Bycatch and access

Chinook and chum observations, defined rates, season and sector.

How do bycatch conditions and avoidance affect access and operations?

Note. Proposed pollock socioeconomic indicators and the questions they address. All require defined indicators and assessment data.

MeasureUnit20202021202220232024
Total catch, all harvesting sectors1,000 t round weight1,370.41,378.11,108.71,314.51,316.3
Retained catch, all harvesting sectors1,000 t round weight1,358.41,363.91,094.91,299.21,298.6
Pollock-target vessels (all harvesting sectors)Vessels117.0116.0114.0105.0103.0
Retained catch, trawl catcher vessels1,000 t round weight725.0718.2570.0678.2678.4
Ex-vessel value, trawl catcher vesselsUS$ million (nominal)233.7242.8242.0244.0213.4
Ex-vessel unit value, trawl catcher vesselsUS$/lb (nominal)0.10.20.20.20.1
Trawl catcher-vessel share of retained catch%53.4%52.7%52.1%52.2%52.2%
Pollock-target catcher vesselsVessels88.084.084.077.076.0

Note. BSAI denotes the Bering Sea and Aleutian Islands and differs from the BS-only assessment catch series. Total catch includes retained and discarded federal and state catch; retained catch and vessel counts cover federal TAC fisheries. The pollock target is assigned by vessel, week, catching mode, NMFS area and gear. Published catcher-vessel counts describe the target-vessel group; only the catch and value rows explicitly marked trawl carry a separate trawl filter. Unit values and shares are derived from rounded published cells; catcher-vessel unit value combines the reported catcher-vessel catch and value across delivery modes. Monetary values are nominal. Values are rounded to one decimal place. Source: Abelman et al. (2026), Tables 4.1, 4.2, 4.9, 4.10 and 4.14 (printed pp. 34–35, 45–46, 48 and 59), using NMFS accounting and production reports and ADF&G COAR data compiled by AKFIN.

Table B6 BSAI Pollock Catch, Participation and Ex-Vessel Economics, 2020–2024
MeasureUnit20202021202220232024
All products, published volume1,000 t product weight492.7464.1387.5480.9487.9
All products, published valueUS$ million (nominal)1,352.91,370.51,400.91,603.01,474.3
All products, unit valueUS$/lb (nominal)1.21.31.61.51.4
At-sea share of published value%60.4%61.7%61.6%55.6%57.9%
Fillets, volume1,000 t product weight149.4UnavailableUnavailable142.9158.6
Fillets, share of published value%37.4%UnavailableUnavailable40.2%40.6%
Fillets, unit valueUS$/lb (nominal)1.5UnavailableUnavailable2.01.7
Surimi, volume1,000 t product weight171.8187.8154.8185.5165.1
Surimi, share of published value%35.2%42.8%37.8%36.0%32.2%
Surimi, unit valueUS$/lb (nominal)1.31.41.61.41.3
Roe, volume1,000 t product weight24.716.013.814.719.2
Roe, share of published value%8.2%6.5%7.1%6.0%7.5%
Roe, unit valueUS$/lb (nominal)2.02.53.33.02.6
At-sea minus shoreside all-product unit valueUS$/lb (nominal)0.40.40.40.10.2

Note. BSAI denotes the Bering Sea and Aleutian Islands. Product weight differs from round-weight retained catch. Published aggregates can be incomplete because confidential components are excluded within a table (Economic SAFE §2.2.6). Fillets combine deep-skin and other fillets and exclude minced fish. Fillet volume, value share and unit value are unavailable for 2021–2022 because shoreside deep-skin components are confidential; unavailable cells are not zeros. Unit values and shares use rounded published values. The at-sea-minus-shoreside unit-value difference is unadjusted for product quality and reflects product mix. All dollar values are nominal. Values are rounded to one decimal place. Source: Abelman et al. (2026), Tables 4.16–4.18 (printed pp. 65, 70 and 74), using NMFS production reports and ADF&G COAR data compiled by AKFIN.

Table B7 BSAI Pollock First-Wholesale Products and Values, 2020–2024
Panel A. Global Alaska Pollock Catch and Shares, 2020–2024
MetricUnit 2020 2021 2022 2023 2024
Global Alaska pollock catchkt live weight 3,544.3 3,484.2 3,380.4 3,543.5 3,573.5
U.S. share of global catchpercent 41.3% 42.0% 36.3% 40.5% 39.9%
Russian share of global catchpercent 51.6% 50.2% 56.3% 53.5% 54.0%
BSAI share of global catchpercent 38.7% 39.6% 32.8% 37.1% 36.8%
Panel B. U.S. Alaska-Pollock Trade, 2020–2025
MetricUnit 2020 2021 2022 2023 2024 2025
Export volumekt product weight 323.5 311.4 274.1 326.3 332.5 333.1
Export valuemillion nominal USD 941.9 898.9 885.6 1,004.4 945.9 1,002.4
Export unit valueUSD/lb product weight 1.3 1.3 1.5 1.4 1.3 1.4
Import value (Alaska + unspecified pollock)million nominal USD 99.7 96.2 141.3 105.5 65.3 48.7
Net exports (legacy basket)million nominal USD 842.2 802.6 744.4 899.0 880.5 953.6
Japan export volume sharepercent 19.3% 21.0% 21.2% 25.0% 19.7% 15.0%
Japan export value sharepercent 20.2% 21.1% 20.1% 22.9% 20.7% 16.6%
China, Taiwan and Hong Kong (legacy aggregate) export volume sharepercent 9.7% 6.8% 11.6% 7.7% 13.3% 10.6%
China, Taiwan and Hong Kong (legacy aggregate) export value sharepercent 6.5% 5.3% 7.5% 5.2% 8.5% 6.7%
Selected European countries export volume sharepercent 37.0% 32.7% 31.4% 32.1% 34.2% 37.1%
Selected European countries export value sharepercent 39.4% 36.3% 35.3% 37.9% 38.6% 40.7%
Meat export volume sharepercent 45.8% 41.1% 42.7% 40.6% 47.5% 53.3%
Meat export value sharepercent 44.0% 40.8% 42.5% 43.4% 48.0% 53.0%
Surimi export volume sharepercent 47.0% 53.8% 52.2% 54.3% 46.3% 40.4%
Surimi export value sharepercent 42.2% 49.4% 49.1% 47.1% 39.1% 34.1%
Roe export volume sharepercent 7.3% 5.1% 5.1% 5.2% 6.2% 6.3%
Roe export value sharepercent 13.8% 9.8% 8.4% 9.5% 13.0% 13.0%

Note. These observed historical statistics cover global catch and shares through 2024 and U.S. trade through 2025. Trade statistics remain revisable. Global catch is in thousand tons of live weight. Trade volumes are thousand tons of product weight. BSAI catch is a subset of U.S. catch and includes federal and state retained plus discarded catch from both the Bering Sea and Aleutian Islands. Trade covers U.S.-national Alaska-pollock products across their source fisheries. Export values are nominal U.S. dollars on a free-alongside-ship (FAS) export-value basis, distinct from wholesale revenue. Unit values reflect product mix as well as market conditions. Domestic exports exclude re-exports. The legacy import basket combines Alaska and unspecified (NSPF) pollock; legacy net exports subtract that broader basket from Alaska-pollock domestic exports. The legacy statistical aggregate combines mainland China, Taiwan and Hong Kong. The selected European aggregate comprises Austria, Belgium, Denmark, France, Germany, Greece, Ireland, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom. It is neither the European Union nor all Europe. Meat combines Alaska-pollock products other than surimi and roe, including frozen whole/headed-and-gutted fish, fillets and other meat. Product shares sum to 100% before rounding. Values are rounded to one decimal place. Displayed net exports are rounded from the saved source totals rather than recalculated from separately rounded export and import values. Sources: NOAA Fisheries FOSS, retrieved 30 October 2026; FAO Global Capture Production release Capture_2026.1.0 (March 2026); Economic SAFE 2025, Table 4.1, p. 34, published 16 March 2026. Source links: NOAA foreign fishery trade data; FAO Global Capture Production; Economic SAFE.

Table B8 Global Alaska Pollock Catch and U.S. Trade
Table B9 Annual Mean Age-0 Pollock Energy Density, 2021–2025

Year

NBS (kJ/g dry mass)

SEBS (kJ/g dry mass)

2021

21.5

20.1

2022

21.5

19.7

2023

21.3

19.8

2024

20.9

19.9

2025

20.8

19.2

Note. Annual mean age-0 pollock energy density for 2021–2025, in kJ/g dry mass. Regions remain separate; sampling uncertainty is pending. Values are rounded to one decimal place. Source: Page and Maselko (2026), DATA sheet.

Table B10 Archived DSEM Pilot Results

Specification

Delta AIC

Residual variance reduction

Maximum gradient

Gradient below 1e-4

Age-0 late-summer SST

0.00

10.5%

1.52e-04

Requires refit

Cold pool + age-0 late-summer SST

1.63

12.0%

5.00e-05

Pass

No-edge reference

2.25

0.0%

5.61e-05

Pass

Cold pool

4.10

0.3%

5.69e-05

Pass

Note. Archived live DSEM pilot results. All Hessians are reported as positive definite. The gradient column applies the strict threshold of 1e-4 independently of the saved OK status.

Table B11 Standardized Direct Proxy Coefficients From the Archived DSEM Pilot

Specification

Pathway

Estimate

95 percent interval

Cold pool

Cold pool

0.041

-0.170 to 0.251

Age-0 late-summer SST

Age-0 SST

-0.222

-0.426 to -0.017

Cold pool + age-0 late-summer SST

Cold pool

-0.069

-0.292 to 0.153

Cold pool + age-0 late-summer SST

Age-0 SST

-0.254

-0.484 to -0.024

Note. Standardized direct proxy coefficients from the archived live DSEM pilot, with approximate 95 percent intervals. These fitted paths remain provisional research estimates.

Figures

Workshop recruitment diagram follows reproductive output through seasonal age-0 and age-1 stages to age-2 observations. Prey-quality and energetic-condition pathways connect to juvenile survival; predation indices and cold-pool extent link to later stages. Rectangular boxes identify candidate observations, and oval nodes describe population states or intermediate processes. These are preliminary hypotheses.

Note. Preliminary Bering Sea recruitment conceptual model reproduced from Monnahan et al. (2026), original Figure 1, printed page 19 (PDF page 27). Source: AFSC Processed Report 2026-09 (Monnahan et al. 2026).

Figure B1 Preliminary Bering Sea Recruitment Conceptual Model
Workshop growth diagram links weight-at-age in year t to previous-year weight, somatic growth, and size-selective mortality. Predation and fishing enter the mortality pathway. Prey availability, pollock and competitor density, genetic diversity, spatial history, temperature, zooplankton, sea ice, salinity, chlorophyll, wind, and currents form candidate interacting pathways. These are preliminary hypotheses.

Note. Preliminary Bering Sea growth conceptual model reproduced from Monnahan et al. (2026), original Figure 2, printed page 20 (PDF page 28). Source: AFSC Processed Report 2026-09 (Monnahan et al. 2026).

Figure B2 Preliminary Bering Sea Growth Conceptual Model
Physical conditions, spawning and larval delivery shape prey access and fall age-0 energy in birth year t. Fall energy affects first-winter survival and age-1 recruitment in t plus 1. Cold-pool extent, juvenile distribution and predator abundance influence overlap and predation after age-1 entry, which affect survival of the cohort to age 3 in t plus 3.

Note. Conceptual cohort sequence from physical conditions and spawning through prey, fall energy, first-winter survival and age-1 recruitment, with subsequent predation affecting survival to age 3. Arrows represent hypotheses supported by the cited literature; they are separate from the fitted direct proxy paths.

Figure B3 Conceptual Cohort Sequence From Spawning Through Age-3 Survival
Separate panels show northern and southeastern Bering Sean annual mean age-0 energy density from 2002 to 2025 in kJ per gram dry mass. The northern series contains 15 observations and the southeastern series 21. Lines break at missing years. Southeastern values peak in 2011, and the 2025 values in both regions are lower than in 2024. Sampling uncertainty is unavailable.

Note. Annual mean age-0 pollock energy density in the northern and southeastern Bering Seas, 2002–2025, in kJ/g dry mass. Points show regional means; lines connect consecutive observed years and break at missing years. Source: Page and Maselko (2026).

Figure B4 Annual Mean Age-0 Pollock Energy Density, 2002–2025

Physical environment and primary production

Physical environment and primary production annual input histories in available-record standard-deviation units. Points are values and lines break at missing years. Latest record years are marked; energy density ends in 2025 and age-1 abundance in 2024. Zero is each series mean; no fitted or imputed values are shown.

Zooplankton and prey

Zooplankton and prey annual input histories in available-record standard-deviation units. Points are values and lines break at missing years. Latest record years are marked; energy density ends in 2025 and age-1 abundance in 2024. Zero is each series mean; no fitted or imputed values are shown.

Fish abundance, energy density and the age-1 response

Fish abundance, energy density and the age-1 response annual input histories in available-record standard-deviation units. Points are values and lines break at missing years. Latest record years are marked; energy density ends in 2025 and age-1 abundance in 2024. Zero is each series mean; no fitted or imputed values are shown.

Note. Annual input histories grouped for readability. Each value is centered on that series’ available-record arithmetic mean and divided by its sample SD, including the latest year. The zero line denotes that mean; gaps are retained without interpolation. Symbols identify values and highlighted endpoints identify each latest record. The panels show 19 annual series. The energy record ends in 2025; the age-1 response ends in 2024. The panels show annual observations rather than DSEM estimates or forecasts.

Figure B5 Indicator Histories in Standardized Units

Two panels show volume and value shares for selected European countries, Japan, and China, Taiwan and Hong Kong during 2020 to 2025. Selected European countries have the largest shares among these groups throughout. Japan shares decrease from 2023 to 2025.

Note. Destination shares of U.S. Alaska pollock domestic exports by (a) product volume and (b) nominal FAS value. The three categories cover part of total exports. Selected European countries are Austria, Belgium, Denmark, France, Germany, Greece, Ireland, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. The combined trade category covers China, Taiwan and Hong Kong. Shares and definitions match Table B8, panel B. Source: (NOAA Fisheries 2026).

Figure B6 U.S. Alaska Pollock Export Destination Shares, 2020–2025

Stacked bars compare meat, surimi and roe shares of export volume and nominal value from 2020 to 2025. Meat exceeds half of both volume and value in 2025. Surimi shares decline after 2023, and roe represents a greater value share than volume share.

Note. Product shares of U.S. Alaska pollock domestic exports by (a) product volume and (b) nominal FAS value. Meat combines products other than surimi and roe, including frozen whole and headed-and-gutted fish and fillets. The one-decimal source shares are rescaled to sum to 100% within each year; the largest adjustment is 0.054 percentage points. Values and product definitions are in Table B8, panel B. Source: (NOAA Fisheries 2026).

Figure B7 U.S. Alaska Pollock Export Product Mix, 2020–2025

Stacked bars show BSAI, other United States, Russian Federation and other countries shares of global Alaska pollock live-weight catch during 2020 to 2024. Russia accounts for more than half in every year; BSAI shares range from 32.8 to 39.6 percent.

Note. Shares of global Alaska pollock capture production by live weight. Other U.S. is the U.S. share minus the BSAI share; other countries is the remainder after the United States and Russian Federation. BSAI includes Bering Sea and Aleutian Islands catch. FAO release Capture_2026.1.0 supplies the global totals; the Economic SAFE supplies BSAI catch. Definitions and totals are in Table B8, panel A. Sources: (FAO 2026); (Abelman et al. 2026).

Figure B8 Global Alaska Pollock Catch by Origin, 2020–2024

Three panels show nominal unit values, product volumes and shares of published first-wholesale value for fillets, surimi and roe from 2020 to 2024. Fillet estimates are missing in 2021 and 2022, with no connecting line across those years. Roe has the highest unit values; surimi volume decreases from 185.5 to 165.1 thousand tons between 2023 and 2024.

Note. BSAI pollock (a) nominal first-wholesale unit values, (b) production in thousand tons of product weight, and (c) shares of published first-wholesale value. Unit values equal total published value times the product value share, divided by product volume and converted to US$/lb; they reflect product mix as well as market conditions. Fillet observations for 2021–2022 are unavailable because confidential shoreside deep-skin components prevent their calculation. Gaps remain missing rather than zero. Other products account for the remaining value share. See Table B7 for definitions. Source: (Abelman et al. 2026).

Figure B9 BSAI Pollock First-Wholesale Product Indicators, 2020–2024

Appendix C
Research and Other Noncommercial Pollock Removals

Reported noncommercial catch

Reported noncommercial pollock catches in the Bering Sea are summarized by collection in Table C1 and by year in Table C2. The AKR dataset covers 1982–2025 across the Gulf of Alaska, Bering Sea and Aleutian Islands; Bering Sea records begin in 1991, with broader multisurvey coverage from 2010. These are reported collection-year amounts, rather than verified complete EBS-stock totals. Missing years and collection cells indicate absent observations. The data end in 2025.

The summaries use the reported Bering Sea FMP area, retaining stations from collections whose names mention other regions. Explicitly Bogoslof-named surveys are shown separately; other collections in reporting area 518 remain among the other reported Bering Sea catches. In 2024, the total was 216.280081 t, including 4.393640 t from the named Bogoslof survey and 211.886441 t from other reported Bering Sea collections. The corresponding 2025 reported total was 140.994428 t.

Experimental fishing permit (EFP) records account for 1,198.506090 t in 2011 and 771.516610 t in 2021. Their inclusion explains the large totals in those years. The sole 2020 record is a Bogoslof collection; other EBS research removals remain unverified for that year. Historical EFP inclusion in official catch accounting requires reconciliation. AKR metadata state that no 2025 EFP catches occurred outside CAS.

Weights are converted from kilograms to tons using the units corroborated by AKR dataset correspondence, dated 9 October and forwarded on 13 October 2026. Annual completeness of the AKR dataset received on 27 October remains unverified. The 2020–2023 totals agree, after rounding, with the accepted 2024 SAFE’s research-catch table (Ianelli et al. 2024). Noncommercial removals are reported separately from assessment catch. The full annual summaries and source record retain the collection details and reporting qualifications.

Exempted fishing and other removal categories

The 2025 EFP 2025-01 permit and 2026 renewal allow up to 3,000 t of total groundfish, rather than pollock alone, to be exempt from TAC during each permit’s effective period; additional groundfish catch counts against TAC. This authorization ceiling is separate from observed removals. Actual pollock catch under these permits and its accounting treatment require permit-specific records.

EFP 2024-02 provides a footrope/gear exemption and otherwise retains applicable regulations. It supplies no basis for assuming a TAC exemption. The noncommercial dataset includes BS-labelled subsistence records in 1991 and 1994; complete recent stock-specific subsistence, recreational and other-FMP removals remain unverified.

Tables

Panel A. 1991–2009

Collection (agency)199119941997199920012003200520072009
AFSC Annual Longline Survey (NMFS)NANA1.02.14.03.11.10.91.4
Subsistence Fishery (ADFG)<0.1<0.1NANANANANANANA

Panel B. 2010–2017

Collection (agency)20102011201220132014201520162017
AFSC Annual Longline Survey (NMFS)NA3.9NA2.3NA3.4NA1.6
Aleutian Island Bottom Trawl Survey (NMFS)27.0NA4.5NA12.3NA2.6NA
Bering Sea Acoustic Survey (NMFS)49.6NANANANANANANA
Bering Sea Bottom Trawl Survey (NMFS)140.7NANANANANANANA
Bering Sea Slope Survey (NMFS)3.3NA7.7NANANA12.4NA
Bogoslof EIT Survey with Northern Extensions (NMFS)NANA4.1NANANANANA
Eastern Bering Sea Bottom Trawl Survey (NMFS)NA116.5140.0178.7293.4249.7177.4181.1
Gulf of Alaska Bottom Trawl Survey (NMFS)NA<0.1NA<0.1NA<0.1NANA
IPHC Annual Longline Survey (IPHC)0.70.20.10.20.60.70.90.1
Large-Mesh Trawl Survey (ADFG)3.73.22.42.21.42.14.65.0
Northern Bering Sea Bottom Trawl Survey (NMFS)0.6NANANANANANA38.1
Pollock EFP 11-01 (NMFS)NA1,198.53.8NANANANANA
Pribilof Islands Crab Survey (ADFG)NA0.1NANANANA0.3NA
St. Matthews Crab Survey (ADFG)0.2NANANANANANA0.2
Summer EBS Survey with Russia (NMFS)NANA45.2NANANANANA

Panel C. 2018–2025

Collection (agency)20182019202020212022202320242025
AFSC Annual Longline Survey (NMFS)NA1.3NA0.9NA0.7NANA
Aleutian Island Bottom Trawl Survey (NMFS)6.1NANANA9.7NA5.0NA
BSAI Trawl Salmon Excluder Device EFP 2018-03-02 (NMFS)NANANA771.5NANANANA
Blue King Crab Pot Survey (ADFG)<0.1NANANA0.1NANANA
Bogoslof Island Walleye Pollock Acoustic-Trawl Survey (NMFS)6.0NANANANANANANA
Eastern Bering Sea Bottom Trawl Survey (NMFS)111.7188.4NA107.8168.1118.0163.2120.4
Eastern Bering Sea Walleye Pollock Acoustic-Trawl Survey (NMFS)36.7NANANA48.3NANANA
Gulf of Alaska Bottom Trawl Survey (NMFS)NA<0.1NANANA<0.1NANA
IPHC Annual Longline Survey (IPHC)0.10.1NA<0.10.2NA0.1NA
Large-Mesh Trawl Survey (ADFG)1.81.8NA1.46.10.73.82.1
Northern Bering Sea Bottom Trawl Survey (NMFS)15.038.6NA16.013.1NANA18.5
Summer Acoustic-Trawl Survey of Walleye Pollock in the Eastern Bering Sea (NMFS)NANANANANANA39.8NA
Winter Acoustic-Trawl Survey of Walleye Pollock Near Bogoslof Island and vicinity (NMFS)NANA12.9NANANA4.4NA

Note. Values are metric tons (source kilograms divided by 1,000), rounded to one decimal place. Source: received Noncommercial Fishery Catch (1).csv, 27 October 2026 received-date field. Reported records have FMP Area = BS and Species Group Code = PLCK. All reporting areas are retained, including 518. NA indicates missing records; 0.0 indicates a reported zero. Early panels show observed BS years only, and collection rows with no records in a panel are omitted from that panel. All collection-year cells and full source precision are retained in the accompanying CSV. Scope follows the FMP field, including collections whose names mention other regions. Positive amounts that round to 0.0 t are shown as <0.1; 0.0 denotes a source zero.

Table C1 Reported Bering Sea Noncommercial Pollock Catch by Collection and Year
Collection yearReported BS total (t)EFP (t)Explicitly Bogoslof-named (t)Other reported BS (t)Source records
1991<0.1NANA<0.11
1992NANANANANA
1993NANANANANA
1994<0.1NANA<0.11
1995NANANANANA
1996NANANANANA
19971.0NANA1.04
1998NANANANANA
19992.1NANA2.14
2000NANANANANA
20014.0NANA4.04
2002NANANANANA
20033.1NANA3.14
2004NANANANANA
20051.1NANA1.13
2006NANANANANA
20070.9NANA0.94
2008NANANANANA
20091.4NANA1.44
2010226.0NANA226.065
20111,322.51,198.5NA124.030
2012207.93.84.1200.038
2013183.4NANA183.456
2014307.7NANA307.726
2015255.9NANA255.930
2016198.1NANA198.132
2017226.1NANA226.129
2018177.4NA6.0171.438
2019230.1NANA230.129
202012.9NA12.9NA1
2021897.6771.5NA126.134
2022245.7NANA245.740
2023119.4NANA119.419
2024216.3NA4.4211.933
2025141.0NANA141.020
2026NANANANANA

Note. Weights are metric tons, rounded to one decimal place. Categories are mutually exclusive source-label summaries. EFP comprises the two explicitly EFP-named collections; the Bogoslof column includes collections explicitly named for Bogoslof. Other reported BS includes all remaining BS-labelled records, including area-518 records from other collections. NA indicates missing records; 0.0 indicates a reported zero. The row count measures records. Totals cover the reported records; annual coverage and overlap with official catch accounting remain uncertain.

Table C2 Annual Reported Bering Sea Pollock Catch by Source Category

Appendix D
Detailed Current-Model Estimates

All estimated parameters and their asymptotic uncertainty are listed below (Table D1), followed by the largest parameter correlations (Table D2). These estimates use the selected model and fixed biological schedules. The full numerical products also retain natural-scale transformations and all shared parameter positions.

Table D1 Model 26.0 Estimated Parameters and Approximate 95% Confidence Intervals
Complete parameter estimates and uncertainty
ID Group Parameter context Estimate SE 95% lower 95% upper
P0001 Recruitment level R0 9.6728 0.1212 9.4352 9.9104
P0002 Recruitment deviation 1964 −1.0198 0.4681 −1.9373 −0.1023
P0003 Recruitment deviation 1965 0.3917 0.2916 −0.1798 0.9632
P0004 Recruitment deviation 1966 0.0001 0.3593 −0.7041 0.7042
P0005 Recruitment deviation 1967 0.5387 0.2917 −0.0330 1.1104
P0006 Recruitment deviation 1968 0.3459 0.3165 −0.2745 0.9662
P0007 Recruitment deviation 1969 0.5038 0.2931 −0.0705 1.0782
P0008 Recruitment deviation 1970 0.3846 0.3052 −0.2136 0.9828
P0009 Recruitment deviation 1971 −0.1528 0.3739 −0.8856 0.5800
P0010 Recruitment deviation 1972 −0.3766 0.3851 −1.1314 0.3782
P0011 Recruitment deviation 1973 0.5213 0.2325 0.0655 0.9770
P0012 Recruitment deviation 1974 0.1941 0.2371 −0.2706 0.6589
P0013 Recruitment deviation 1975 0.0354 0.2205 −0.3967 0.4675
P0014 Recruitment deviation 1976 −0.2044 0.2104 −0.6169 0.2081
P0015 Recruitment deviation 1977 −0.1243 0.1911 −0.4989 0.2503
P0016 Recruitment deviation 1978 0.5126 0.1555 0.2078 0.8175
P0017 Recruitment deviation 1979 1.3692 0.1375 1.0997 1.6387
P0018 Recruitment deviation 1980 0.6249 0.1492 0.3324 0.9174
P0019 Recruitment deviation 1981 0.7685 0.1463 0.4817 1.0553
P0020 Recruitment deviation 1982 0.1889 0.1614 −0.1274 0.5052
P0021 Recruitment deviation 1983 1.1863 0.1357 0.9204 1.4521
P0022 Recruitment deviation 1984 −0.1097 0.1634 −0.4299 0.2104
P0023 Recruitment deviation 1985 0.7176 0.1390 0.4450 0.9901
P0024 Recruitment deviation 1986 −0.2200 0.1558 −0.5254 0.0853
P0025 Recruitment deviation 1987 −0.7740 0.1648 −1.0971 −0.4510
P0026 Recruitment deviation 1988 −1.0224 0.1658 −1.3474 −0.6974
P0027 Recruitment deviation 1989 −0.2878 0.1424 −0.5669 −0.0086
P0028 Recruitment deviation 1990 1.1562 0.1262 0.9090 1.4035
P0029 Recruitment deviation 1991 0.5442 0.1307 0.2881 0.8003
P0030 Recruitment deviation 1992 0.4032 0.1325 0.1436 0.6628
P0031 Recruitment deviation 1993 1.0698 0.1269 0.8211 1.3186
P0032 Recruitment deviation 1994 0.0032 0.1356 −0.2625 0.2690
P0033 Recruitment deviation 1995 −0.3517 0.1389 −0.6239 −0.0794
P0034 Recruitment deviation 1996 0.3553 0.1292 0.1020 0.6086
P0035 Recruitment deviation 1997 0.6464 0.1269 0.3977 0.8950
P0036 Recruitment deviation 1998 −0.0602 0.1317 −0.3183 0.1978
P0037 Recruitment deviation 1999 0.0094 0.1306 −0.2466 0.2654
P0038 Recruitment deviation 2000 0.4371 0.1273 0.1876 0.6866
P0039 Recruitment deviation 2001 0.7735 0.1252 0.5281 1.0189
P0040 Recruitment deviation 2002 0.3678 0.1265 0.1199 0.6157
P0041 Recruitment deviation 2003 −0.1019 0.1286 −0.3540 0.1502
P0042 Recruitment deviation 2004 −0.8894 0.1362 −1.1564 −0.6224
P0043 Recruitment deviation 2005 −1.2337 0.1415 −1.5110 −0.9563
P0044 Recruitment deviation 2006 −0.3192 0.1309 −0.5758 −0.0627
P0045 Recruitment deviation 2007 0.4533 0.1271 0.2041 0.7025
P0046 Recruitment deviation 2008 −0.1584 0.1330 −0.4192 0.1024
P0047 Recruitment deviation 2009 1.1374 0.1249 0.8925 1.3823
P0048 Recruitment deviation 2010 0.3763 0.1287 0.1240 0.6287
P0049 Recruitment deviation 2011 −0.1110 0.1328 −0.3713 0.1493
P0050 Recruitment deviation 2012 −0.2546 0.1337 −0.5166 0.0074
P0051 Recruitment deviation 2013 1.0028 0.1249 0.7580 1.2475
P0052 Recruitment deviation 2014 1.1366 0.1252 0.8912 1.3819
P0053 Recruitment deviation 2015 0.2917 0.1313 0.0344 0.5490
P0054 Recruitment deviation 2016 −0.6103 0.1475 −0.8995 −0.3212
P0055 Recruitment deviation 2017 −0.6994 0.1519 −0.9971 −0.4018
P0056 Recruitment deviation 2018 0.0578 0.1410 −0.2187 0.3342
P0057 Recruitment deviation 2019 1.7104 0.1302 1.4552 1.9656
P0058 Recruitment deviation 2020 0.5518 0.1454 0.2667 0.8368
P0059 Recruitment deviation 2021 −0.2033 0.1786 −0.5534 0.1467
P0060 Recruitment deviation 2022 −0.2247 0.2049 −0.6263 0.1768
P0061 Recruitment deviation 2023 −0.3126 0.2286 −0.7606 0.1353
P0062 Recruitment deviation 2024 0.9050 0.2517 0.4118 1.3983
P0063 Recruitment deviation 2025 0.5663 0.2920 −0.0060 1.1387
P0064 Recruitment deviation 2026 0.8281 0.5378 −0.2260 1.8822
P0065 Initial-age deviation Age1 −0.3949 0.3509 −1.0827 0.2928
P0066 Initial-age deviation Age2 −0.4683 0.3455 −1.1455 0.2089
P0067 Initial-age deviation Age3 −1.2468 0.4532 −2.1351 −0.3586
P0068 Initial-age deviation Age4 −1.4797 0.5231 −2.5049 −0.4545
P0069 Initial-age deviation Age5 −0.9725 0.4745 −1.9026 −0.0424
P0070 Initial-age deviation Age6 −1.1558 0.5508 −2.2353 −0.0762
P0071 Initial-age deviation Age7 −1.3132 0.6310 −2.5499 −0.0765
P0072 Initial-age deviation Age8 −1.2359 0.6710 −2.5510 0.0791
P0073 Initial-age deviation Age9 −1.0702 0.6957 −2.4338 0.2934
P0074 Initial-age deviation Age10 −0.9172 0.7220 −2.3322 0.4979
P0075 Initial-age deviation Age11 −0.7788 0.7491 −2.2470 0.6894
P0076 Initial-age deviation Age12 −0.6579 0.7760 −2.1789 0.8631
P0077 Initial-age deviation Age13 −0.5491 0.8035 −2.1239 1.0256
P0078 Initial-age deviation Age14 −1.0041 0.7100 −2.3957 0.3874
P0079 Log fishing scale Fishery; 1964 −2.9386 0.2174 −3.3647 −2.5125
P0080 Log fishing scale Fishery; 1965 −2.7303 0.2116 −3.1450 −2.3155
P0081 Log fishing scale Fishery; 1966 −2.6737 0.2155 −3.0960 −2.2513
P0082 Log fishing scale Fishery; 1967 −2.0362 0.2270 −2.4811 −1.5913
P0083 Log fishing scale Fishery; 1968 −1.9723 0.2260 −2.4153 −1.5292
P0084 Log fishing scale Fishery; 1969 −1.9071 0.2317 −2.3611 −1.4530
P0085 Log fishing scale Fishery; 1970 −1.5364 0.2309 −1.9890 −1.0838
P0086 Log fishing scale Fishery; 1971 −1.1811 0.2325 −1.6368 −0.7254
P0087 Log fishing scale Fishery; 1972 −1.0495 0.2265 −1.4935 −0.6055
P0088 Log fishing scale Fishery; 1973 −0.9062 0.2295 −1.3561 −0.4563
P0089 Log fishing scale Fishery; 1974 −0.8209 0.2280 −1.2679 −0.3740
P0090 Log fishing scale Fishery; 1975 −0.9945 0.2055 −1.3973 −0.5916
P0091 Log fishing scale Fishery; 1976 −1.0737 0.2009 −1.4673 −0.6800
P0092 Log fishing scale Fishery; 1977 −1.1394 0.2153 −1.5614 −0.7174
P0093 Log fishing scale Fishery; 1978 −1.0271 0.2171 −1.4525 −0.6017
P0094 Log fishing scale Fishery; 1979 −0.9874 0.2107 −1.4003 −0.5745
P0095 Log fishing scale Fishery; 1980 −1.0814 0.1983 −1.4701 −0.6927
P0096 Log fishing scale Fishery; 1981 −1.4230 0.1935 −1.8023 −1.0438
P0097 Log fishing scale Fishery; 1982 −1.8679 0.1901 −2.2404 −1.4954
P0098 Log fishing scale Fishery; 1983 −2.0507 0.1833 −2.4100 −1.6914
P0099 Log fishing scale Fishery; 1984 −2.0663 0.1527 −2.3655 −1.7671
P0100 Log fishing scale Fishery; 1985 −2.0559 0.1408 −2.3318 −1.7801
P0101 Log fishing scale Fishery; 1986 −2.1239 0.1347 −2.3878 −1.8599
P0102 Log fishing scale Fishery; 1987 −2.4130 0.1266 −2.6611 −2.1649
P0103 Log fishing scale Fishery; 1988 −2.0653 0.1178 −2.2962 −1.8344
P0104 Log fishing scale Fishery; 1989 −2.0069 0.1006 −2.2040 −1.8098
P0105 Log fishing scale Fishery; 1990 −1.5822 0.0944 −1.7672 −1.3972
P0106 Log fishing scale Fishery; 1991 −1.4032 0.0849 −1.5696 −1.2368
P0107 Log fishing scale Fishery; 1992 −1.1200 0.0920 −1.3004 −0.9396
P0108 Log fishing scale Fishery; 1993 −1.5672 0.1086 −1.7800 −1.3543
P0109 Log fishing scale Fishery; 1994 −1.8109 0.1176 −2.0413 −1.5804
P0110 Log fishing scale Fishery; 1995 −1.8155 0.1118 −2.0347 −1.5964
P0111 Log fishing scale Fishery; 1996 −1.6567 0.1114 −1.8751 −1.4383
P0112 Log fishing scale Fishery; 1997 −1.6452 0.1244 −1.8890 −1.4014
P0113 Log fishing scale Fishery; 1998 −1.8130 0.1174 −2.0431 −1.5830
P0114 Log fishing scale Fishery; 1999 −2.0245 0.1131 −2.2463 −1.8028
P0115 Log fishing scale Fishery; 2000 −1.9078 0.0941 −2.0923 −1.7232
P0116 Log fishing scale Fishery; 2001 −1.7581 0.0844 −1.9236 −1.5926
P0117 Log fishing scale Fishery; 2002 −1.5902 0.0776 −1.7424 −1.4381
P0118 Log fishing scale Fishery; 2003 −1.5098 0.0772 −1.6611 −1.3585
P0119 Log fishing scale Fishery; 2004 −1.5953 0.0838 −1.7596 −1.4311
P0120 Log fishing scale Fishery; 2005 −1.6359 0.0829 −1.7985 −1.4734
P0121 Log fishing scale Fishery; 2006 −1.4267 0.0820 −1.5873 −1.2660
P0122 Log fishing scale Fishery; 2007 −1.3555 0.0809 −1.5141 −1.1970
P0123 Log fishing scale Fishery; 2008 −1.2726 0.0841 −1.4374 −1.1078
P0124 Log fishing scale Fishery; 2009 −1.3188 0.0943 −1.5036 −1.1341
P0125 Log fishing scale Fishery; 2010 −1.5006 0.1034 −1.7033 −1.2978
P0126 Log fishing scale Fishery; 2011 −1.1973 0.1005 −1.3944 −1.0003
P0127 Log fishing scale Fishery; 2012 −1.2027 0.1268 −1.4512 −0.9542
P0128 Log fishing scale Fishery; 2013 −1.2580 0.1457 −1.5435 −0.9725
P0129 Log fishing scale Fishery; 2014 −1.3178 0.1579 −1.6272 −1.0085
P0130 Log fishing scale Fishery; 2015 −1.2383 0.1649 −1.5615 −0.9152
P0131 Log fishing scale Fishery; 2016 −1.5367 0.1456 −1.8220 −1.2513
P0132 Log fishing scale Fishery; 2017 −1.5614 0.1284 −1.8130 −1.3097
P0133 Log fishing scale Fishery; 2018 −1.7471 0.1197 −1.9818 −1.5124
P0134 Log fishing scale Fishery; 2019 −1.6372 0.1073 −1.8475 −1.4269
P0135 Log fishing scale Fishery; 2020 −1.3656 0.1186 −1.5980 −1.1331
P0136 Log fishing scale Fishery; 2021 −1.4188 0.1220 −1.6579 −1.1798
P0137 Log fishing scale Fishery; 2022 −1.7708 0.1385 −2.0422 −1.4993
P0138 Log fishing scale Fishery; 2023 −1.8165 0.1494 −2.1092 −1.5238
P0139 Log fishing scale Fishery; 2024 −1.9059 0.1439 −2.1878 −1.6239
P0140 Log fishing scale Fishery; 2025 −1.8131 0.1338 −2.0753 −1.5508
P0141 Log fishing scale Fishery; 2026 −1.6691 0.1614 −1.9853 −1.3528
P0142 Log catchability AVO −8.2249 0.0711 −8.3642 −8.0855
P0143 Log catchability ATS −0.6599 0.0620 −0.7814 −0.5384
P0144 Log catchability CPUE −0.2481 0.1849 −0.6104 0.1143
P0145 Selectivity increment Fishery; Bin1; 1964 * 1.2875 0.5969 0.1177 2.4573
P0146 Selectivity increment Fishery; Bin2; 1964 * 0.7997 0.4928 −0.1663 1.7656
P0147 Selectivity increment Fishery; Bin3; 1964 * 0.4574 0.4383 −0.4016 1.3164
P0148 Selectivity increment Fishery; Bin4; 1964 * 0.3677 0.3979 −0.4122 1.1476
P0149 Selectivity increment Fishery; Bin5; 1964 * −0.1820 0.3965 −0.9591 0.5952
P0150 Selectivity increment Fishery; Bin6; 1964 * −0.4579 0.2958 −1.0377 0.1219
P0151 Selectivity increment Fishery; Bin7; 1964 * −0.5719 0.2747 −1.1103 −0.0335
P0152 Selectivity increment Fishery; Bin8; 1964 * −0.5861 0.2680 −1.1114 −0.0608
P0153 Selectivity increment Fishery; Bin9; 1964 * −0.4992 0.2677 −1.0239 0.0255
P0154 Selectivity increment Fishery; Bin10; 1964 * −0.2953 0.2716 −0.8277 0.2371
P0155 Selectivity increment Fishery; Bin11; 1964 * −0.2831 0.2799 −0.8317 0.2654
P0156 Selectivity increment Fishery; Bin12; 1964 * −0.0367 0.2934 −0.6117 0.5383
P0157 Selectivity increment Fishery; Bin1; 1965 * 0.3571 0.4151 −0.4565 1.1708
P0158 Selectivity increment Fishery; Bin2; 1965 * 0.1619 0.4026 −0.6272 0.9511
P0159 Selectivity increment Fishery; Bin3; 1965 * 0.1307 0.3944 −0.6423 0.9037
P0160 Selectivity increment Fishery; Bin4; 1965 * 0.0902 0.3777 −0.6500 0.8304
P0161 Selectivity increment Fishery; Bin5; 1965 * −0.0379 0.3792 −0.7810 0.7053
P0162 Selectivity increment Fishery; Bin6; 1965 * −0.1784 0.3055 −0.7771 0.4203
P0163 Selectivity increment Fishery; Bin7; 1965 * −0.1639 0.2839 −0.7203 0.3926
P0164 Selectivity increment Fishery; Bin8; 1965 * −0.1318 0.2797 −0.6799 0.4163
P0165 Selectivity increment Fishery; Bin9; 1965 * −0.0992 0.2797 −0.6475 0.4491
P0166 Selectivity increment Fishery; Bin10; 1965 * −0.0684 0.2813 −0.6198 0.4830
P0167 Selectivity increment Fishery; Bin11; 1965 * −0.0439 0.2832 −0.5990 0.5111
P0168 Selectivity increment Fishery; Bin12; 1965 * −0.0165 0.2786 −0.5626 0.5295
P0169 Selectivity increment Fishery; Bin1; 1966 * 0.3379 0.4159 −0.4772 1.1530
P0170 Selectivity increment Fishery; Bin2; 1966 * 0.1962 0.4019 −0.5915 0.9838
P0171 Selectivity increment Fishery; Bin3; 1966 * 0.1357 0.3933 −0.6351 0.9065
P0172 Selectivity increment Fishery; Bin4; 1966 * −0.0528 0.3090 −0.6585 0.5528
P0173 Selectivity increment Fishery; Bin5; 1966 * −0.0653 0.2844 −0.6227 0.4921
P0174 Selectivity increment Fishery; Bin6; 1966 * −0.0912 0.2786 −0.6373 0.4549
P0175 Selectivity increment Fishery; Bin7; 1966 * −0.0904 0.2774 −0.6341 0.4534
P0176 Selectivity increment Fishery; Bin8; 1966 * −0.0915 0.2773 −0.6350 0.4519
P0177 Selectivity increment Fishery; Bin9; 1966 * −0.0850 0.2779 −0.6298 0.4597
P0178 Selectivity increment Fishery; Bin10; 1966 * −0.0744 0.2795 −0.6221 0.4733
P0179 Selectivity increment Fishery; Bin11; 1966 * −0.0638 0.2811 −0.6149 0.4872
P0180 Selectivity increment Fishery; Bin12; 1966 * −0.0553 0.2749 −0.5940 0.4834
P0181 Selectivity increment Fishery; Bin1; 1967 * 0.3044 0.4161 −0.5112 1.1200
P0182 Selectivity increment Fishery; Bin2; 1967 * 0.1602 0.3988 −0.6214 0.9418
P0183 Selectivity increment Fishery; Bin3; 1967 * 0.2062 0.3907 −0.5595 0.9719
P0184 Selectivity increment Fishery; Bin4; 1967 * −0.1132 0.3085 −0.7179 0.4915
P0185 Selectivity increment Fishery; Bin5; 1967 * −0.1023 0.2828 −0.6566 0.4520
P0186 Selectivity increment Fishery; Bin6; 1967 * −0.0914 0.2781 −0.6364 0.4536
P0187 Selectivity increment Fishery; Bin7; 1967 * −0.0794 0.2773 −0.6229 0.4641
P0188 Selectivity increment Fishery; Bin8; 1967 * −0.0677 0.2772 −0.6110 0.4757
P0189 Selectivity increment Fishery; Bin9; 1967 * −0.0629 0.2779 −0.6075 0.4818
P0190 Selectivity increment Fishery; Bin10; 1967 * −0.0573 0.2794 −0.6049 0.4904
P0191 Selectivity increment Fishery; Bin11; 1967 * −0.0511 0.2811 −0.6020 0.4998
P0192 Selectivity increment Fishery; Bin12; 1967 * −0.0455 0.2747 −0.5838 0.4928
P0193 Selectivity increment Fishery; Bin1; 1968 * 0.3127 0.4163 −0.5033 1.1286
P0194 Selectivity increment Fishery; Bin2; 1968 * 0.1419 0.3978 −0.6377 0.9215
P0195 Selectivity increment Fishery; Bin3; 1968 * 0.0120 0.3855 −0.7436 0.7675
P0196 Selectivity increment Fishery; Bin4; 1968 * −0.0108 0.3097 −0.6179 0.5963
P0197 Selectivity increment Fishery; Bin5; 1968 * −0.0366 0.2850 −0.5952 0.5220
P0198 Selectivity increment Fishery; Bin6; 1968 * −0.0514 0.2793 −0.5988 0.4960
P0199 Selectivity increment Fishery; Bin7; 1968 * −0.0611 0.2781 −0.6061 0.4839
P0200 Selectivity increment Fishery; Bin8; 1968 * −0.0644 0.2790 −0.6113 0.4824
P0201 Selectivity increment Fishery; Bin9; 1968 * −0.0626 0.2800 −0.6114 0.4863
P0202 Selectivity increment Fishery; Bin10; 1968 * −0.0612 0.2825 −0.6149 0.4925
P0203 Selectivity increment Fishery; Bin11; 1968 * −0.0596 0.2834 −0.6150 0.4958
P0204 Selectivity increment Fishery; Bin12; 1968 * −0.0589 0.2764 −0.6007 0.4829
P0205 Selectivity increment Fishery; Bin1; 1969 * 0.2851 0.4165 −0.5312 1.1014
P0206 Selectivity increment Fishery; Bin2; 1969 * 0.0924 0.3968 −0.6852 0.8701
P0207 Selectivity increment Fishery; Bin3; 1969 * 0.1579 0.3857 −0.5981 0.9139
P0208 Selectivity increment Fishery; Bin4; 1969 * −0.0960 0.3101 −0.7037 0.5117
P0209 Selectivity increment Fishery; Bin5; 1969 * −0.0947 0.2880 −0.6590 0.4697
P0210 Selectivity increment Fishery; Bin6; 1969 * −0.0822 0.2892 −0.6490 0.4846
P0211 Selectivity increment Fishery; Bin7; 1969 * −0.0710 0.3110 −0.6805 0.5385
P0212 Selectivity increment Fishery; Bin8; 1969 * −0.0543 0.3363 −0.7134 0.6047
P0213 Selectivity increment Fishery; Bin9; 1969 * −0.0484 0.3372 −0.7094 0.6125
P0214 Selectivity increment Fishery; Bin10; 1969 * −0.0360 0.4001 −0.8201 0.7481
P0215 Selectivity increment Fishery; Bin11; 1969 * −0.0272 0.3244 −0.6629 0.6085
P0216 Selectivity increment Fishery; Bin12; 1969 * −0.0257 0.2858 −0.5858 0.5345
P0217 Selectivity increment Fishery; Bin1; 1970 * 0.3011 0.4170 −0.5161 1.1183
P0218 Selectivity increment Fishery; Bin2; 1970 * 0.1488 0.3965 −0.6283 0.9259
P0219 Selectivity increment Fishery; Bin3; 1970 * −0.0316 0.3840 −0.7843 0.7211
P0220 Selectivity increment Fishery; Bin4; 1970 * −0.2072 0.3635 −0.9196 0.5052
P0221 Selectivity increment Fishery; Bin5; 1970 * −0.1218 0.3161 −0.7413 0.4976
P0222 Selectivity increment Fishery; Bin6; 1970 * −0.1011 0.3166 −0.7217 0.5194
P0223 Selectivity increment Fishery; Bin7; 1970 * −0.0529 0.3685 −0.7751 0.6693
P0224 Selectivity increment Fishery; Bin8; 1970 * −0.0096 0.3991 −0.7920 0.7727
P0225 Selectivity increment Fishery; Bin9; 1970 * −0.0009 0.3998 −0.7845 0.7828
P0226 Selectivity increment Fishery; Bin10; 1970 * 0.0133 0.4076 −0.7855 0.8122
P0227 Selectivity increment Fishery; Bin11; 1970 * 0.0230 0.4049 −0.7706 0.8167
P0228 Selectivity increment Fishery; Bin12; 1970 * 0.0389 0.3034 −0.5557 0.6335
P0229 Selectivity increment Fishery; Bin1; 1971 * 0.0965 0.4172 −0.7211 0.9142
P0230 Selectivity increment Fishery; Bin2; 1971 * 0.0278 0.3955 −0.7474 0.8031
P0231 Selectivity increment Fishery; Bin3; 1971 * −0.0921 0.3808 −0.8385 0.6544
P0232 Selectivity increment Fishery; Bin4; 1971 * −0.0308 0.3714 −0.7587 0.6972
P0233 Selectivity increment Fishery; Bin5; 1971 * 0.0085 0.3196 −0.6179 0.6350
P0234 Selectivity increment Fishery; Bin6; 1971 * −0.0046 0.3151 −0.6222 0.6129
P0235 Selectivity increment Fishery; Bin7; 1971 * −0.0485 0.3697 −0.7730 0.6761
P0236 Selectivity increment Fishery; Bin8; 1971 * 0.0021 0.4013 −0.7845 0.7887
P0237 Selectivity increment Fishery; Bin9; 1971 * 0.0038 0.4016 −0.7833 0.7910
P0238 Selectivity increment Fishery; Bin10; 1971 * 0.0043 0.4080 −0.7953 0.8040
P0239 Selectivity increment Fishery; Bin11; 1971 * 0.0104 0.4051 −0.7835 0.8044
P0240 Selectivity increment Fishery; Bin12; 1971 * 0.0224 0.3007 −0.5671 0.6118
P0241 Selectivity increment Fishery; Bin1; 1972 * −0.1540 0.4171 −0.9715 0.6635
P0242 Selectivity increment Fishery; Bin2; 1972 * 0.1905 0.3966 −0.5868 0.9678
P0243 Selectivity increment Fishery; Bin3; 1972 * 0.0918 0.3791 −0.6513 0.8349
P0244 Selectivity increment Fishery; Bin4; 1972 * 0.0742 0.3605 −0.6324 0.7808
P0245 Selectivity increment Fishery; Bin5; 1972 * −0.0186 0.3073 −0.6208 0.5836
P0246 Selectivity increment Fishery; Bin6; 1972 * −0.0055 0.2955 −0.5847 0.5738
P0247 Selectivity increment Fishery; Bin7; 1972 * −0.0047 0.3201 −0.6322 0.6227
P0248 Selectivity increment Fishery; Bin8; 1972 * −0.0323 0.4015 −0.8192 0.7546
P0249 Selectivity increment Fishery; Bin9; 1972 * −0.0229 0.4016 −0.8100 0.7641
P0250 Selectivity increment Fishery; Bin10; 1972 * −0.0315 0.4079 −0.8311 0.7680
P0251 Selectivity increment Fishery; Bin11; 1972 * −0.0396 0.4049 −0.8332 0.7540
P0252 Selectivity increment Fishery; Bin12; 1972 * −0.0473 0.3006 −0.6364 0.5419
P0253 Selectivity increment Fishery; Bin1; 1973 * −0.1854 0.4165 −1.0018 0.6309
P0254 Selectivity increment Fishery; Bin2; 1973 * 0.1006 0.3966 −0.6767 0.8779
P0255 Selectivity increment Fishery; Bin3; 1973 * 0.0425 0.3793 −0.7010 0.7860
P0256 Selectivity increment Fishery; Bin4; 1973 * 0.0386 0.3526 −0.6525 0.7298
P0257 Selectivity increment Fishery; Bin5; 1973 * 0.0410 0.3027 −0.5522 0.6342
P0258 Selectivity increment Fishery; Bin6; 1973 * 0.0434 0.2924 −0.5296 0.6165
P0259 Selectivity increment Fishery; Bin7; 1973 * 0.0391 0.3170 −0.5822 0.6604
P0260 Selectivity increment Fishery; Bin8; 1973 * 0.0045 0.3969 −0.7735 0.7825
P0261 Selectivity increment Fishery; Bin9; 1973 * −0.0153 0.3987 −0.7967 0.7660
P0262 Selectivity increment Fishery; Bin10; 1973 * −0.0262 0.4063 −0.8225 0.7701
P0263 Selectivity increment Fishery; Bin11; 1973 * −0.0364 0.4038 −0.8279 0.7550
P0264 Selectivity increment Fishery; Bin12; 1973 * −0.0463 0.3011 −0.6364 0.5438
P0265 Selectivity increment Fishery; Bin1; 1974 * −0.1610 0.4155 −0.9753 0.6534
P0266 Selectivity increment Fishery; Bin2; 1974 * 0.1384 0.3933 −0.6324 0.9092
P0267 Selectivity increment Fishery; Bin3; 1974 * 0.1528 0.3689 −0.5702 0.8759
P0268 Selectivity increment Fishery; Bin4; 1974 * 0.0118 0.3473 −0.6690 0.6926
P0269 Selectivity increment Fishery; Bin5; 1974 * 0.0042 0.3027 −0.5891 0.5975
P0270 Selectivity increment Fishery; Bin6; 1974 * −0.0021 0.2923 −0.5750 0.5709
P0271 Selectivity increment Fishery; Bin7; 1974 * −0.0010 0.3158 −0.6200 0.6180
P0272 Selectivity increment Fishery; Bin8; 1974 * −0.0203 0.3456 −0.6978 0.6571
P0273 Selectivity increment Fishery; Bin9; 1974 * −0.0200 0.3422 −0.6907 0.6507
P0274 Selectivity increment Fishery; Bin10; 1974 * −0.0257 0.4021 −0.8137 0.7624
P0275 Selectivity increment Fishery; Bin11; 1974 * −0.0326 0.4002 −0.8171 0.7518
P0276 Selectivity increment Fishery; Bin12; 1974 * −0.0446 0.3017 −0.6360 0.5468
P0277 Selectivity increment Fishery; Bin1; 1975 * −0.1574 0.4148 −0.9705 0.6557
P0278 Selectivity increment Fishery; Bin2; 1975 * −0.1858 0.3879 −0.9460 0.5745
P0279 Selectivity increment Fishery; Bin3; 1975 * 0.1323 0.3078 −0.4710 0.7357
P0280 Selectivity increment Fishery; Bin4; 1975 * 0.0781 0.2842 −0.4789 0.6351
P0281 Selectivity increment Fishery; Bin5; 1975 * 0.0430 0.2808 −0.5074 0.5933
P0282 Selectivity increment Fishery; Bin6; 1975 * 0.0290 0.2859 −0.5313 0.5893
P0283 Selectivity increment Fishery; Bin7; 1975 * 0.0231 0.3077 −0.5801 0.6262
P0284 Selectivity increment Fishery; Bin8; 1975 * 0.0028 0.3377 −0.6589 0.6646
P0285 Selectivity increment Fishery; Bin9; 1975 * 0.0035 0.3448 −0.6722 0.6792
P0286 Selectivity increment Fishery; Bin10; 1975 * 0.0104 0.3139 −0.6049 0.6257
P0287 Selectivity increment Fishery; Bin11; 1975 * 0.0105 0.2910 −0.5598 0.5807
P0288 Selectivity increment Fishery; Bin12; 1975 * 0.0104 0.2783 −0.5351 0.5558
P0289 Selectivity increment Fishery; Bin1; 1976 * −0.1591 0.4145 −0.9714 0.6533
P0290 Selectivity increment Fishery; Bin2; 1976 * −0.0964 0.3884 −0.8577 0.6650
P0291 Selectivity increment Fishery; Bin3; 1976 * −0.0776 0.3491 −0.7618 0.6066
P0292 Selectivity increment Fishery; Bin4; 1976 * 0.0621 0.3017 −0.5292 0.6534
P0293 Selectivity increment Fishery; Bin5; 1976 * 0.0496 0.2832 −0.5055 0.6048
P0294 Selectivity increment Fishery; Bin6; 1976 * 0.0379 0.2801 −0.5111 0.5870
P0295 Selectivity increment Fishery; Bin7; 1976 * 0.0310 0.2819 −0.5214 0.5835
P0296 Selectivity increment Fishery; Bin8; 1976 * 0.0269 0.2950 −0.5513 0.6051
P0297 Selectivity increment Fishery; Bin9; 1976 * 0.0252 0.3416 −0.6443 0.6947
P0298 Selectivity increment Fishery; Bin10; 1976 * 0.0334 0.3214 −0.5965 0.6633
P0299 Selectivity increment Fishery; Bin11; 1976 * 0.0339 0.2922 −0.5388 0.6066
P0300 Selectivity increment Fishery; Bin12; 1976 * 0.0329 0.2785 −0.5129 0.5787
P0301 Selectivity increment Fishery; Bin1; 1977 * −0.1490 0.4140 −0.9604 0.6624
P0302 Selectivity increment Fishery; Bin2; 1977 * −0.0115 0.3875 −0.7709 0.7479
P0303 Selectivity increment Fishery; Bin3; 1977 * −0.1853 0.3694 −0.9094 0.5387
P0304 Selectivity increment Fishery; Bin4; 1977 * −0.0719 0.3558 −0.7692 0.6254
P0305 Selectivity increment Fishery; Bin5; 1977 * 0.0195 0.3047 −0.5777 0.6167
P0306 Selectivity increment Fishery; Bin6; 1977 * 0.0338 0.2861 −0.5269 0.5945
P0307 Selectivity increment Fishery; Bin7; 1977 * 0.0379 0.2880 −0.5266 0.6024
P0308 Selectivity increment Fishery; Bin8; 1977 * 0.0395 0.3108 −0.5697 0.6487
P0309 Selectivity increment Fishery; Bin9; 1977 * 0.0514 0.3946 −0.7220 0.8247
P0310 Selectivity increment Fishery; Bin10; 1977 * 0.0697 0.3962 −0.7069 0.8463
P0311 Selectivity increment Fishery; Bin11; 1977 * 0.0816 0.3251 −0.5556 0.7189
P0312 Selectivity increment Fishery; Bin12; 1977 * 0.0844 0.2885 −0.4811 0.6498
P0313 Selectivity increment Fishery; Bin1; 1978 * −0.1935 0.4131 −1.0032 0.6162
P0314 Selectivity increment Fishery; Bin2; 1978 * −0.1580 0.3803 −0.9035 0.5874
P0315 Selectivity increment Fishery; Bin3; 1978 * −0.0660 0.3645 −0.7803 0.6483
P0316 Selectivity increment Fishery; Bin4; 1978 * −0.0381 0.3640 −0.7515 0.6753
P0317 Selectivity increment Fishery; Bin5; 1978 * 0.0269 0.3143 −0.5891 0.6429
P0318 Selectivity increment Fishery; Bin6; 1978 * 0.0307 0.3083 −0.5736 0.6349
P0319 Selectivity increment Fishery; Bin7; 1978 * 0.0457 0.3154 −0.5725 0.6639
P0320 Selectivity increment Fishery; Bin8; 1978 * 0.0496 0.3259 −0.5891 0.6883
P0321 Selectivity increment Fishery; Bin9; 1978 * 0.0673 0.3989 −0.7144 0.8491
P0322 Selectivity increment Fishery; Bin10; 1978 * 0.0741 0.3989 −0.7076 0.8559
P0323 Selectivity increment Fishery; Bin11; 1978 * 0.0807 0.3341 −0.5741 0.7354
P0324 Selectivity increment Fishery; Bin12; 1978 * 0.0808 0.2890 −0.4856 0.6472
P0325 Selectivity increment Fishery; Bin1; 1979 * −0.1527 0.4072 −0.9509 0.6455
P0326 Selectivity increment Fishery; Bin2; 1979 * −0.3807 0.3608 −1.0879 0.3265
P0327 Selectivity increment Fishery; Bin3; 1979 * −0.1744 0.3505 −0.8614 0.5126
P0328 Selectivity increment Fishery; Bin4; 1979 * −0.0494 0.3568 −0.7488 0.6499
P0329 Selectivity increment Fishery; Bin5; 1979 * 0.0853 0.3491 −0.5990 0.7695
P0330 Selectivity increment Fishery; Bin6; 1979 * 0.1164 0.3292 −0.5289 0.7617
P0331 Selectivity increment Fishery; Bin7; 1979 * 0.0994 0.3399 −0.5669 0.7656
P0332 Selectivity increment Fishery; Bin8; 1979 * 0.1032 0.3687 −0.6194 0.8257
P0333 Selectivity increment Fishery; Bin9; 1979 * 0.1059 0.4008 −0.6796 0.8914
P0334 Selectivity increment Fishery; Bin10; 1979 * 0.0896 0.3983 −0.6910 0.8703
P0335 Selectivity increment Fishery; Bin11; 1979 * 0.0792 0.3286 −0.5649 0.7232
P0336 Selectivity increment Fishery; Bin12; 1979 * 0.0784 0.2878 −0.4856 0.6424
P0337 Selectivity increment Fishery; Bin1; 1980 * −0.1661 0.4085 −0.9667 0.6344
P0338 Selectivity increment Fishery; Bin2; 1980 * −0.4732 0.3535 −1.1660 0.2197
P0339 Selectivity increment Fishery; Bin3; 1980 * −0.2547 0.3436 −0.9282 0.4188
P0340 Selectivity increment Fishery; Bin4; 1980 * 0.0750 0.3564 −0.6234 0.7734
P0341 Selectivity increment Fishery; Bin5; 1980 * 0.1095 0.3585 −0.5930 0.8121
P0342 Selectivity increment Fishery; Bin6; 1980 * 0.1351 0.3138 −0.4800 0.7502
P0343 Selectivity increment Fishery; Bin7; 1980 * 0.1332 0.3106 −0.4757 0.7420
P0344 Selectivity increment Fishery; Bin8; 1980 * 0.1202 0.3686 −0.6023 0.8427
P0345 Selectivity increment Fishery; Bin9; 1980 * 0.0907 0.3988 −0.6909 0.8722
P0346 Selectivity increment Fishery; Bin10; 1980 * 0.0826 0.3937 −0.6891 0.8542
P0347 Selectivity increment Fishery; Bin11; 1980 * 0.0751 0.3175 −0.5472 0.6975
P0348 Selectivity increment Fishery; Bin12; 1980 * 0.0726 0.2867 −0.4893 0.6345
P0349 Selectivity increment Fishery; Bin1; 1981 * −0.1370 0.4123 −0.9450 0.6710
P0350 Selectivity increment Fishery; Bin2; 1981 * −0.2530 0.3700 −0.9782 0.4722
P0351 Selectivity increment Fishery; Bin3; 1981 * −0.2579 0.3394 −0.9230 0.4072
P0352 Selectivity increment Fishery; Bin4; 1981 * 0.0107 0.3493 −0.6739 0.6953
P0353 Selectivity increment Fishery; Bin5; 1981 * 0.1230 0.3471 −0.5573 0.8033
P0354 Selectivity increment Fishery; Bin6; 1981 * 0.0783 0.3012 −0.5121 0.6686
P0355 Selectivity increment Fishery; Bin7; 1981 * 0.0847 0.2895 −0.4827 0.6522
P0356 Selectivity increment Fishery; Bin8; 1981 * 0.0882 0.3089 −0.5172 0.6936
P0357 Selectivity increment Fishery; Bin9; 1981 * 0.0812 0.3921 −0.6872 0.8497
P0358 Selectivity increment Fishery; Bin10; 1981 * 0.0626 0.3238 −0.5721 0.6973
P0359 Selectivity increment Fishery; Bin11; 1981 * 0.0595 0.2952 −0.5191 0.6382
P0360 Selectivity increment Fishery; Bin12; 1981 * 0.0596 0.2817 −0.4925 0.6117
P0361 Selectivity increment Fishery; Bin1; 1982 * −0.1040 0.4154 −0.9182 0.7102
P0362 Selectivity increment Fishery; Bin2; 1982 * −0.0931 0.3823 −0.8423 0.6562
P0363 Selectivity increment Fishery; Bin3; 1982 * −0.3008 0.3536 −0.9937 0.3922
P0364 Selectivity increment Fishery; Bin4; 1982 * −0.0092 0.3403 −0.6762 0.6579
P0365 Selectivity increment Fishery; Bin5; 1982 * 0.0660 0.3012 −0.5244 0.6565
P0366 Selectivity increment Fishery; Bin6; 1982 * 0.0694 0.2805 −0.4804 0.6193
P0367 Selectivity increment Fishery; Bin7; 1982 * 0.0670 0.2772 −0.4763 0.6104
P0368 Selectivity increment Fishery; Bin8; 1982 * 0.0685 0.2771 −0.4746 0.6116
P0369 Selectivity increment Fishery; Bin9; 1982 * 0.0662 0.2794 −0.4813 0.6137
P0370 Selectivity increment Fishery; Bin10; 1982 * 0.0600 0.2812 −0.4911 0.6111
P0371 Selectivity increment Fishery; Bin11; 1982 * 0.0560 0.2836 −0.5000 0.6119
P0372 Selectivity increment Fishery; Bin12; 1982 * 0.0538 0.2777 −0.4905 0.5981
P0373 Selectivity increment Fishery; Bin1; 1983 * −0.1223 0.4165 −0.9386 0.6940
P0374 Selectivity increment Fishery; Bin2; 1983 * 0.1032 0.3892 −0.6597 0.8660
P0375 Selectivity increment Fishery; Bin3; 1983 * −0.0970 0.3645 −0.8113 0.6174
P0376 Selectivity increment Fishery; Bin4; 1983 * −0.1890 0.3452 −0.8656 0.4876
P0377 Selectivity increment Fishery; Bin5; 1983 * −0.0624 0.3207 −0.6909 0.5661
P0378 Selectivity increment Fishery; Bin6; 1983 * 0.0676 0.2926 −0.5059 0.6410
P0379 Selectivity increment Fishery; Bin7; 1983 * 0.0552 0.2786 −0.4908 0.6012
P0380 Selectivity increment Fishery; Bin8; 1983 * 0.0486 0.2766 −0.4935 0.5906
P0381 Selectivity increment Fishery; Bin9; 1983 * 0.0482 0.2775 −0.4956 0.5921
P0382 Selectivity increment Fishery; Bin10; 1983 * 0.0497 0.2797 −0.4985 0.5978
P0383 Selectivity increment Fishery; Bin11; 1983 * 0.0494 0.2820 −0.5033 0.6021
P0384 Selectivity increment Fishery; Bin12; 1983 * 0.0488 0.2760 −0.4922 0.5898
P0385 Selectivity increment Fishery; Bin1; 1984 * −0.1099 0.4185 −0.9301 0.7102
P0386 Selectivity increment Fishery; Bin2; 1984 * −0.1521 0.3905 −0.9174 0.6132
P0387 Selectivity increment Fishery; Bin3; 1984 * 0.0489 0.3700 −0.6763 0.7742
P0388 Selectivity increment Fishery; Bin4; 1984 * −0.0874 0.3505 −0.7743 0.5996
P0389 Selectivity increment Fishery; Bin5; 1984 * 0.0264 0.3403 −0.6405 0.6933
P0390 Selectivity increment Fishery; Bin6; 1984 * 0.0367 0.2951 −0.5417 0.6151
P0391 Selectivity increment Fishery; Bin7; 1984 * 0.0512 0.2785 −0.4946 0.5970
P0392 Selectivity increment Fishery; Bin8; 1984 * 0.0411 0.2762 −0.5002 0.5824
P0393 Selectivity increment Fishery; Bin9; 1984 * 0.0380 0.2771 −0.5051 0.5811
P0394 Selectivity increment Fishery; Bin10; 1984 * 0.0360 0.2792 −0.5113 0.5833
P0395 Selectivity increment Fishery; Bin11; 1984 * 0.0358 0.2814 −0.5158 0.5874
P0396 Selectivity increment Fishery; Bin12; 1984 * 0.0354 0.2754 −0.5043 0.5751
P0397 Selectivity increment Fishery; Bin1; 1985 * −0.1272 0.4190 −0.9484 0.6940
P0398 Selectivity increment Fishery; Bin2; 1985 * 0.0402 0.3949 −0.7338 0.8141
P0399 Selectivity increment Fishery; Bin3; 1985 * 0.1307 0.3677 −0.5900 0.8513
P0400 Selectivity increment Fishery; Bin4; 1985 * −0.0902 0.3563 −0.7885 0.6081
P0401 Selectivity increment Fishery; Bin5; 1985 * −0.2409 0.3470 −0.9210 0.4392
P0402 Selectivity increment Fishery; Bin6; 1985 * 0.0564 0.2947 −0.5213 0.6340
P0403 Selectivity increment Fishery; Bin7; 1985 * 0.0519 0.2754 −0.4879 0.5917
P0404 Selectivity increment Fishery; Bin8; 1985 * 0.0500 0.2751 −0.4892 0.5891
P0405 Selectivity increment Fishery; Bin9; 1985 * 0.0345 0.2765 −0.5074 0.5765
P0406 Selectivity increment Fishery; Bin10; 1985 * 0.0325 0.2789 −0.5141 0.5790
P0407 Selectivity increment Fishery; Bin11; 1985 * 0.0318 0.2811 −0.5191 0.5827
P0408 Selectivity increment Fishery; Bin12; 1985 * 0.0304 0.2749 −0.5084 0.5693
P0409 Selectivity increment Fishery; Bin1; 1986 * −0.1344 0.4196 −0.9569 0.6881
P0410 Selectivity increment Fishery; Bin2; 1986 * −0.0383 0.3972 −0.8168 0.7401
P0411 Selectivity increment Fishery; Bin3; 1986 * 0.0606 0.3691 −0.6628 0.7840
P0412 Selectivity increment Fishery; Bin4; 1986 * 0.1677 0.3543 −0.5267 0.8622
P0413 Selectivity increment Fishery; Bin5; 1986 * −0.0207 0.3550 −0.7164 0.6751
P0414 Selectivity increment Fishery; Bin6; 1986 * −0.0709 0.3319 −0.7214 0.5796
P0415 Selectivity increment Fishery; Bin7; 1986 * 0.0143 0.2940 −0.5620 0.5905
P0416 Selectivity increment Fishery; Bin8; 1986 * −0.0173 0.2782 −0.5626 0.5279
P0417 Selectivity increment Fishery; Bin9; 1986 * 0.0089 0.2789 −0.5378 0.5555
P0418 Selectivity increment Fishery; Bin10; 1986 * 0.0072 0.2788 −0.5393 0.5537
P0419 Selectivity increment Fishery; Bin11; 1986 * 0.0093 0.2807 −0.5408 0.5594
P0420 Selectivity increment Fishery; Bin12; 1986 * 0.0136 0.2745 −0.5244 0.5517
P0421 Selectivity increment Fishery; Bin1; 1987 * −0.1333 0.4198 −0.9561 0.6895
P0422 Selectivity increment Fishery; Bin2; 1987 * −0.0846 0.4008 −0.8702 0.7009
P0423 Selectivity increment Fishery; Bin3; 1987 * 0.1086 0.3713 −0.6192 0.8364
P0424 Selectivity increment Fishery; Bin4; 1987 * −0.1061 0.3582 −0.8082 0.5959
P0425 Selectivity increment Fishery; Bin5; 1987 * 0.0218 0.3538 −0.6717 0.7153
P0426 Selectivity increment Fishery; Bin6; 1987 * −0.0462 0.3557 −0.7433 0.6509
P0427 Selectivity increment Fishery; Bin7; 1987 * −0.0955 0.3359 −0.7538 0.5628
P0428 Selectivity increment Fishery; Bin8; 1987 * 0.1044 0.2962 −0.4762 0.6850
P0429 Selectivity increment Fishery; Bin9; 1987 * 0.0984 0.2793 −0.4491 0.6459
P0430 Selectivity increment Fishery; Bin10; 1987 * 0.0660 0.2781 −0.4791 0.6112
P0431 Selectivity increment Fishery; Bin11; 1987 * 0.0418 0.2801 −0.5072 0.5908
P0432 Selectivity increment Fishery; Bin12; 1987 * 0.0248 0.2743 −0.5127 0.5624
P0433 Selectivity increment Fishery; Bin1; 1988 * −0.1650 0.4198 −0.9878 0.6577
P0434 Selectivity increment Fishery; Bin2; 1988 * −0.1229 0.4025 −0.9118 0.6660
P0435 Selectivity increment Fishery; Bin3; 1988 * 0.4321 0.3737 −0.3003 1.1645
P0436 Selectivity increment Fishery; Bin4; 1988 * 0.0242 0.3611 −0.6835 0.7320
P0437 Selectivity increment Fishery; Bin5; 1988 * 0.0879 0.3542 −0.6062 0.7820
P0438 Selectivity increment Fishery; Bin6; 1988 * −0.0565 0.3542 −0.7508 0.6377
P0439 Selectivity increment Fishery; Bin7; 1988 * 0.1187 0.3368 −0.5414 0.7788
P0440 Selectivity increment Fishery; Bin8; 1988 * −0.0812 0.2935 −0.6565 0.4941
P0441 Selectivity increment Fishery; Bin9; 1988 * −0.0785 0.2772 −0.6218 0.4648
P0442 Selectivity increment Fishery; Bin10; 1988 * −0.0796 0.2776 −0.6236 0.4644
P0443 Selectivity increment Fishery; Bin11; 1988 * −0.0497 0.2829 −0.6042 0.5048
P0444 Selectivity increment Fishery; Bin12; 1988 * −0.0295 0.2753 −0.5690 0.5100
P0445 Selectivity increment Fishery; Bin1; 1989 * −0.1307 0.4196 −0.9531 0.6916
P0446 Selectivity increment Fishery; Bin2; 1989 * −0.0816 0.4021 −0.8696 0.7065
P0447 Selectivity increment Fishery; Bin3; 1989 * −0.3948 0.3821 −1.1437 0.3540
P0448 Selectivity increment Fishery; Bin4; 1989 * 0.1355 0.3658 −0.5814 0.8525
P0449 Selectivity increment Fishery; Bin5; 1989 * 0.0220 0.3542 −0.6723 0.7163
P0450 Selectivity increment Fishery; Bin6; 1989 * 0.0546 0.3531 −0.6374 0.7466
P0451 Selectivity increment Fishery; Bin7; 1989 * 0.1293 0.2978 −0.4543 0.7130
P0452 Selectivity increment Fishery; Bin8; 1989 * 0.1041 0.2772 −0.4392 0.6473
P0453 Selectivity increment Fishery; Bin9; 1989 * 0.0309 0.2754 −0.5088 0.5706
P0454 Selectivity increment Fishery; Bin10; 1989 * 0.0641 0.2773 −0.4795 0.6076
P0455 Selectivity increment Fishery; Bin11; 1989 * 0.0445 0.2815 −0.5072 0.5962
P0456 Selectivity increment Fishery; Bin12; 1989 * 0.0221 0.2747 −0.5163 0.5605
P0457 Selectivity increment Fishery; Bin1; 1990 * −0.1246 0.4192 −0.9462 0.6971
P0458 Selectivity increment Fishery; Bin2; 1990 * −0.0556 0.3998 −0.8392 0.7279
P0459 Selectivity increment Fishery; Bin3; 1990 * −0.3454 0.3826 −1.0953 0.4046
P0460 Selectivity increment Fishery; Bin4; 1990 * 0.0258 0.3704 −0.7002 0.7518
P0461 Selectivity increment Fishery; Bin5; 1990 * 0.1451 0.3528 −0.5464 0.8366
P0462 Selectivity increment Fishery; Bin6; 1990 * 0.0542 0.3493 −0.6303 0.7387
P0463 Selectivity increment Fishery; Bin7; 1990 * −0.0416 0.3272 −0.6830 0.5997
P0464 Selectivity increment Fishery; Bin8; 1990 * 0.0504 0.2894 −0.5169 0.6176
P0465 Selectivity increment Fishery; Bin9; 1990 * 0.0621 0.2804 −0.4875 0.6116
P0466 Selectivity increment Fishery; Bin10; 1990 * 0.0002 0.2925 −0.5731 0.5736
P0467 Selectivity increment Fishery; Bin11; 1990 * 0.1328 0.2978 −0.4508 0.7164
P0468 Selectivity increment Fishery; Bin12; 1990 * 0.0966 0.2719 −0.4364 0.6295
P0469 Selectivity increment Fishery; Bin1; 1991 * −0.0571 0.4181 −0.8765 0.7624
P0470 Selectivity increment Fishery; Bin2; 1991 * −0.0210 0.3915 −0.7883 0.7462
P0471 Selectivity increment Fishery; Bin3; 1991 * −0.3596 0.3748 −1.0942 0.3750
P0472 Selectivity increment Fishery; Bin4; 1991 * −0.2984 0.3583 −1.0006 0.4038
P0473 Selectivity increment Fishery; Bin5; 1991 * −0.1882 0.3484 −0.8710 0.4946
P0474 Selectivity increment Fishery; Bin6; 1991 * −0.0522 0.3230 −0.6853 0.5809
P0475 Selectivity increment Fishery; Bin7; 1991 * 0.1413 0.3233 −0.4924 0.7750
P0476 Selectivity increment Fishery; Bin8; 1991 * −0.0373 0.2924 −0.6104 0.5359
P0477 Selectivity increment Fishery; Bin9; 1991 * 0.1423 0.2774 −0.4014 0.6859
P0478 Selectivity increment Fishery; Bin10; 1991 * 0.0714 0.2959 −0.5085 0.6513
P0479 Selectivity increment Fishery; Bin11; 1991 * 0.3360 0.2985 −0.2491 0.9211
P0480 Selectivity increment Fishery; Bin12; 1991 * 0.3228 0.2650 −0.1966 0.8421
P0481 Selectivity increment Fishery; Bin1; 1992 * −0.1291 0.4153 −0.9430 0.6848
P0482 Selectivity increment Fishery; Bin2; 1992 * −0.0575 0.3344 −0.7129 0.5978
P0483 Selectivity increment Fishery; Bin3; 1992 * 0.5222 0.3061 −0.0779 1.1222
P0484 Selectivity increment Fishery; Bin4; 1992 * −0.2344 0.3156 −0.8530 0.3842
P0485 Selectivity increment Fishery; Bin5; 1992 * −0.3277 0.3180 −0.9509 0.2955
P0486 Selectivity increment Fishery; Bin6; 1992 * −0.0479 0.3127 −0.6607 0.5649
P0487 Selectivity increment Fishery; Bin7; 1992 * −0.0629 0.2927 −0.6365 0.5108
P0488 Selectivity increment Fishery; Bin8; 1992 * 0.2020 0.2872 −0.3608 0.7648
P0489 Selectivity increment Fishery; Bin9; 1992 * 0.0885 0.2802 −0.4607 0.6377
P0490 Selectivity increment Fishery; Bin10; 1992 * 0.2149 0.2878 −0.3491 0.7790
P0491 Selectivity increment Fishery; Bin11; 1992 * −0.1178 0.2882 −0.6827 0.4471
P0492 Selectivity increment Fishery; Bin12; 1992 * −0.0503 0.2607 −0.5612 0.4607
P0493 Selectivity increment Fishery; Bin1; 1993 * −0.1187 0.4147 −0.9315 0.6940
P0494 Selectivity increment Fishery; Bin2; 1993 * −0.4719 0.3522 −1.1621 0.2184
P0495 Selectivity increment Fishery; Bin3; 1993 * −0.0290 0.2736 −0.5654 0.5073
P0496 Selectivity increment Fishery; Bin4; 1993 * 0.8219 0.2800 0.2731 1.3708
P0497 Selectivity increment Fishery; Bin5; 1993 * 0.0377 0.3059 −0.5619 0.6373
P0498 Selectivity increment Fishery; Bin6; 1993 * 0.0368 0.3239 −0.5980 0.6717
P0499 Selectivity increment Fishery; Bin7; 1993 * 0.0738 0.3239 −0.5609 0.7086
P0500 Selectivity increment Fishery; Bin8; 1993 * −0.0135 0.2905 −0.5830 0.5559
P0501 Selectivity increment Fishery; Bin9; 1993 * −0.0312 0.2806 −0.5812 0.5188
P0502 Selectivity increment Fishery; Bin10; 1993 * −0.0706 0.2792 −0.6178 0.4766
P0503 Selectivity increment Fishery; Bin11; 1993 * −0.1520 0.3012 −0.7423 0.4384
P0504 Selectivity increment Fishery; Bin12; 1993 * −0.0833 0.2738 −0.6200 0.4534
P0505 Selectivity increment Fishery; Bin1; 1994 * −0.0143 0.4166 −0.8309 0.8023
P0506 Selectivity increment Fishery; Bin2; 1994 * 0.0152 0.3582 −0.6868 0.7172
P0507 Selectivity increment Fishery; Bin3; 1994 * −0.7774 0.3087 −1.3825 −0.1722
P0508 Selectivity increment Fishery; Bin4; 1994 * −0.3070 0.2656 −0.8275 0.2136
P0509 Selectivity increment Fishery; Bin5; 1994 * 0.9075 0.2652 0.3877 1.4273
P0510 Selectivity increment Fishery; Bin6; 1994 * 0.2876 0.3068 −0.3137 0.8890
P0511 Selectivity increment Fishery; Bin7; 1994 * 0.0218 0.3155 −0.5966 0.6402
P0512 Selectivity increment Fishery; Bin8; 1994 * −0.0271 0.2831 −0.5820 0.5277
P0513 Selectivity increment Fishery; Bin9; 1994 * −0.0449 0.2690 −0.5721 0.4824
P0514 Selectivity increment Fishery; Bin10; 1994 * −0.0192 0.2727 −0.5538 0.5153
P0515 Selectivity increment Fishery; Bin11; 1994 * 0.0142 0.2870 −0.5483 0.5767
P0516 Selectivity increment Fishery; Bin12; 1994 * −0.0564 0.2782 −0.6018 0.4889
P0517 Selectivity increment Fishery; Bin1; 1995 * 0.0094 0.4170 −0.8078 0.8267
P0518 Selectivity increment Fishery; Bin2; 1995 * 0.1923 0.3679 −0.5288 0.9134
P0519 Selectivity increment Fishery; Bin3; 1995 * −0.2946 0.3221 −0.9259 0.3368
P0520 Selectivity increment Fishery; Bin4; 1995 * −0.7007 0.2923 −1.2736 −0.1279
P0521 Selectivity increment Fishery; Bin5; 1995 * −0.3795 0.2662 −0.9013 0.1423
P0522 Selectivity increment Fishery; Bin6; 1995 * 0.4455 0.2661 −0.0760 0.9671
P0523 Selectivity increment Fishery; Bin7; 1995 * 0.1832 0.2782 −0.3621 0.7285
P0524 Selectivity increment Fishery; Bin8; 1995 * 0.1784 0.2707 −0.3522 0.7090
P0525 Selectivity increment Fishery; Bin9; 1995 * 0.1368 0.2714 −0.3951 0.6687
P0526 Selectivity increment Fishery; Bin10; 1995 * 0.1109 0.2724 −0.4231 0.6449
P0527 Selectivity increment Fishery; Bin11; 1995 * 0.0758 0.2748 −0.4628 0.6143
P0528 Selectivity increment Fishery; Bin12; 1995 * 0.0424 0.2681 −0.4831 0.5680
P0529 Selectivity increment Fishery; Bin1; 1996 * −0.0097 0.4173 −0.8277 0.8083
P0530 Selectivity increment Fishery; Bin2; 1996 * 0.5075 0.3722 −0.2219 1.2369
P0531 Selectivity increment Fishery; Bin3; 1996 * 0.2794 0.3348 −0.3768 0.9357
P0532 Selectivity increment Fishery; Bin4; 1996 * −0.7854 0.3054 −1.3840 −0.1867
P0533 Selectivity increment Fishery; Bin5; 1996 * −0.7408 0.2866 −1.3026 −0.1790
P0534 Selectivity increment Fishery; Bin6; 1996 * −0.3569 0.2674 −0.8811 0.1672
P0535 Selectivity increment Fishery; Bin7; 1996 * 0.2781 0.2585 −0.2285 0.7847
P0536 Selectivity increment Fishery; Bin8; 1996 * 0.3081 0.2639 −0.2091 0.8253
P0537 Selectivity increment Fishery; Bin9; 1996 * 0.2215 0.2701 −0.3080 0.7510
P0538 Selectivity increment Fishery; Bin10; 1996 * 0.1476 0.2737 −0.3889 0.6841
P0539 Selectivity increment Fishery; Bin11; 1996 * 0.0906 0.2752 −0.4489 0.6301
P0540 Selectivity increment Fishery; Bin12; 1996 * 0.0601 0.2678 −0.4648 0.5849
P0541 Selectivity increment Fishery; Bin1; 1997 * −0.1094 0.4177 −0.9282 0.7093
P0542 Selectivity increment Fishery; Bin2; 1997 * 0.3323 0.3622 −0.3776 1.0422
P0543 Selectivity increment Fishery; Bin3; 1997 * 0.1555 0.3403 −0.5114 0.8224
P0544 Selectivity increment Fishery; Bin4; 1997 * 0.6559 0.3059 0.0563 1.2556
P0545 Selectivity increment Fishery; Bin5; 1997 * −0.0012 0.2806 −0.5511 0.5488
P0546 Selectivity increment Fishery; Bin6; 1997 * −0.3984 0.2751 −0.9376 0.1409
P0547 Selectivity increment Fishery; Bin7; 1997 * −0.4036 0.2694 −0.9315 0.1243
P0548 Selectivity increment Fishery; Bin8; 1997 * −0.2889 0.2735 −0.8249 0.2471
P0549 Selectivity increment Fishery; Bin9; 1997 * −0.0227 0.2787 −0.5690 0.5235
P0550 Selectivity increment Fishery; Bin10; 1997 * 0.0186 0.2746 −0.5197 0.5569
P0551 Selectivity increment Fishery; Bin11; 1997 * 0.0284 0.2758 −0.5121 0.5689
P0552 Selectivity increment Fishery; Bin12; 1997 * 0.0335 0.2671 −0.4900 0.5570
P0553 Selectivity increment Fishery; Bin1; 1998 * −0.0772 0.4183 −0.8971 0.7427
P0554 Selectivity increment Fishery; Bin2; 1998 * −0.3764 0.3344 −1.0318 0.2791
P0555 Selectivity increment Fishery; Bin3; 1998 * 0.2778 0.3214 −0.3521 0.9077
P0556 Selectivity increment Fishery; Bin4; 1998 * 0.2308 0.3062 −0.3693 0.8309
P0557 Selectivity increment Fishery; Bin5; 1998 * 0.1763 0.2739 −0.3605 0.7132
P0558 Selectivity increment Fishery; Bin6; 1998 * 0.2773 0.2583 −0.2290 0.7837
P0559 Selectivity increment Fishery; Bin7; 1998 * −0.2341 0.2704 −0.7642 0.2960
P0560 Selectivity increment Fishery; Bin8; 1998 * −0.0717 0.2888 −0.6378 0.4944
P0561 Selectivity increment Fishery; Bin9; 1998 * −0.0713 0.2812 −0.6223 0.4798
P0562 Selectivity increment Fishery; Bin10; 1998 * −0.0478 0.2738 −0.5845 0.4889
P0563 Selectivity increment Fishery; Bin11; 1998 * −0.0464 0.2758 −0.5870 0.4942
P0564 Selectivity increment Fishery; Bin12; 1998 * −0.0374 0.2688 −0.5643 0.4895
P0565 Selectivity increment Fishery; Bin1; 1999 * −0.1247 0.4186 −0.9452 0.6958
P0566 Selectivity increment Fishery; Bin2; 1999 * −0.3584 0.3509 −1.0462 0.3294
P0567 Selectivity increment Fishery; Bin3; 1999 * 0.8134 0.2823 0.2601 1.3666
P0568 Selectivity increment Fishery; Bin4; 1999 * 0.4525 0.2907 −0.1172 1.0221
P0569 Selectivity increment Fishery; Bin5; 1999 * 0.1329 0.2861 −0.4279 0.6938
P0570 Selectivity increment Fishery; Bin6; 1999 * −0.2625 0.2614 −0.7749 0.2499
P0571 Selectivity increment Fishery; Bin7; 1999 * 0.2338 0.2526 −0.2613 0.7289
P0572 Selectivity increment Fishery; Bin8; 1999 * −0.1112 0.2746 −0.6493 0.4269
P0573 Selectivity increment Fishery; Bin9; 1999 * −0.2599 0.2671 −0.7833 0.2636
P0574 Selectivity increment Fishery; Bin10; 1999 * −0.2373 0.2691 −0.7648 0.2901
P0575 Selectivity increment Fishery; Bin11; 1999 * −0.1704 0.2922 −0.7431 0.4023
P0576 Selectivity increment Fishery; Bin12; 1999 * −0.1081 0.2841 −0.6649 0.4487
P0577 Selectivity increment Fishery; Bin1; 2000 * −0.0558 0.4185 −0.8761 0.7645
P0578 Selectivity increment Fishery; Bin2; 2000 * −0.1443 0.3623 −0.8544 0.5658
P0579 Selectivity increment Fishery; Bin3; 2000 * −0.5590 0.2797 −1.1072 −0.0108
P0580 Selectivity increment Fishery; Bin4; 2000 * 0.2946 0.2566 −0.2083 0.7976
P0581 Selectivity increment Fishery; Bin5; 2000 * 0.4186 0.2725 −0.1155 0.9528
P0582 Selectivity increment Fishery; Bin6; 2000 * −0.0055 0.2800 −0.5544 0.5433
P0583 Selectivity increment Fishery; Bin7; 2000 * −0.0436 0.2605 −0.5542 0.4669
P0584 Selectivity increment Fishery; Bin8; 2000 * 0.2266 0.2481 −0.2597 0.7129
P0585 Selectivity increment Fishery; Bin9; 2000 * 0.0273 0.2558 −0.4741 0.5287
P0586 Selectivity increment Fishery; Bin10; 2000 * −0.0436 0.2647 −0.5624 0.4753
P0587 Selectivity increment Fishery; Bin11; 2000 * −0.0517 0.2881 −0.6163 0.5129
P0588 Selectivity increment Fishery; Bin12; 2000 * −0.0637 0.2858 −0.6239 0.4965
P0589 Selectivity increment Fishery; Bin1; 2001 * −0.0146 0.4182 −0.8342 0.8051
P0590 Selectivity increment Fishery; Bin2; 2001 * −0.2128 0.3639 −0.9260 0.5005
P0591 Selectivity increment Fishery; Bin3; 2001 * −0.4501 0.3107 −1.0591 0.1588
P0592 Selectivity increment Fishery; Bin4; 2001 * −0.3103 0.2707 −0.8409 0.2202
P0593 Selectivity increment Fishery; Bin5; 2001 * 0.2544 0.2536 −0.2428 0.7515
P0594 Selectivity increment Fishery; Bin6; 2001 * 0.6106 0.2699 0.0815 1.1397
P0595 Selectivity increment Fishery; Bin7; 2001 * 0.1237 0.2651 −0.3958 0.6432
P0596 Selectivity increment Fishery; Bin8; 2001 * −0.1064 0.2514 −0.5990 0.3863
P0597 Selectivity increment Fishery; Bin9; 2001 * 0.0296 0.2532 −0.4666 0.5259
P0598 Selectivity increment Fishery; Bin10; 2001 * 0.0467 0.2626 −0.4679 0.5614
P0599 Selectivity increment Fishery; Bin11; 2001 * 0.0368 0.2697 −0.4918 0.5654
P0600 Selectivity increment Fishery; Bin12; 2001 * −0.0076 0.2700 −0.5368 0.5215
P0601 Selectivity increment Fishery; Bin1; 2002 * −0.0584 0.4185 −0.8785 0.7618
P0602 Selectivity increment Fishery; Bin2; 2002 * 0.1591 0.3560 −0.5386 0.8567
P0603 Selectivity increment Fishery; Bin3; 2002 * 0.0693 0.3069 −0.5323 0.6709
P0604 Selectivity increment Fishery; Bin4; 2002 * −0.0089 0.2773 −0.5524 0.5345
P0605 Selectivity increment Fishery; Bin5; 2002 * −0.2313 0.2558 −0.7326 0.2699
P0606 Selectivity increment Fishery; Bin6; 2002 * 0.0666 0.2451 −0.4137 0.5470
P0607 Selectivity increment Fishery; Bin7; 2002 * 0.0798 0.2495 −0.4092 0.5689
P0608 Selectivity increment Fishery; Bin8; 2002 * 0.0548 0.2547 −0.4443 0.5539
P0609 Selectivity increment Fishery; Bin9; 2002 * 0.0383 0.2538 −0.4592 0.5357
P0610 Selectivity increment Fishery; Bin10; 2002 * −0.0247 0.2576 −0.5297 0.4802
P0611 Selectivity increment Fishery; Bin11; 2002 * −0.0785 0.2672 −0.6022 0.4452
P0612 Selectivity increment Fishery; Bin12; 2002 * −0.0660 0.2655 −0.5864 0.4544
P0613 Selectivity increment Fishery; Bin1; 2003 * −0.0709 0.4187 −0.8916 0.7499
P0614 Selectivity increment Fishery; Bin2; 2003 * −0.3090 0.3568 −1.0082 0.3902
P0615 Selectivity increment Fishery; Bin3; 2003 * 0.6699 0.2727 0.1354 1.2045
P0616 Selectivity increment Fishery; Bin4; 2003 * −0.0671 0.2628 −0.5821 0.4478
P0617 Selectivity increment Fishery; Bin5; 2003 * 0.0369 0.2581 −0.4690 0.5428
P0618 Selectivity increment Fishery; Bin6; 2003 * −0.1845 0.2516 −0.6775 0.3085
P0619 Selectivity increment Fishery; Bin7; 2003 * 0.0299 0.2463 −0.4528 0.5126
P0620 Selectivity increment Fishery; Bin8; 2003 * 0.0377 0.2530 −0.4581 0.5336
P0621 Selectivity increment Fishery; Bin9; 2003 * −0.0010 0.2590 −0.5085 0.5066
P0622 Selectivity increment Fishery; Bin10; 2003 * −0.0130 0.2594 −0.5213 0.4954
P0623 Selectivity increment Fishery; Bin11; 2003 * −0.0731 0.2643 −0.5912 0.4449
P0624 Selectivity increment Fishery; Bin12; 2003 * −0.0559 0.2639 −0.5732 0.4614
P0625 Selectivity increment Fishery; Bin1; 2004 * −0.0277 0.4190 −0.8489 0.7936
P0626 Selectivity increment Fishery; Bin2; 2004 * −0.1140 0.3769 −0.8527 0.6247
P0627 Selectivity increment Fishery; Bin3; 2004 * −0.6762 0.2837 −1.2323 −0.1201
P0628 Selectivity increment Fishery; Bin4; 2004 * 0.7169 0.2537 0.2196 1.2142
P0629 Selectivity increment Fishery; Bin5; 2004 * 0.0216 0.2568 −0.4817 0.5249
P0630 Selectivity increment Fishery; Bin6; 2004 * −0.1190 0.2671 −0.6425 0.4044
P0631 Selectivity increment Fishery; Bin7; 2004 * −0.0233 0.2567 −0.5265 0.4799
P0632 Selectivity increment Fishery; Bin8; 2004 * 0.0195 0.2529 −0.4762 0.5151
P0633 Selectivity increment Fishery; Bin9; 2004 * 0.0478 0.2620 −0.4656 0.5613
P0634 Selectivity increment Fishery; Bin10; 2004 * 0.0528 0.2673 −0.4710 0.5766
P0635 Selectivity increment Fishery; Bin11; 2004 * 0.0774 0.2682 −0.4484 0.6031
P0636 Selectivity increment Fishery; Bin12; 2004 * 0.0243 0.2639 −0.4929 0.5415
P0637 Selectivity increment Fishery; Bin1; 2005 * −0.0551 0.4191 −0.8765 0.7662
P0638 Selectivity increment Fishery; Bin2; 2005 * 0.1003 0.3875 −0.6593 0.8598
P0639 Selectivity increment Fishery; Bin3; 2005 * −0.0105 0.3079 −0.6139 0.5929
P0640 Selectivity increment Fishery; Bin4; 2005 * −0.3443 0.2523 −0.8388 0.1502
P0641 Selectivity increment Fishery; Bin5; 2005 * 0.4211 0.2497 −0.0682 0.9104
P0642 Selectivity increment Fishery; Bin6; 2005 * 0.2411 0.2598 −0.2682 0.7503
P0643 Selectivity increment Fishery; Bin7; 2005 * −0.1040 0.2576 −0.6089 0.4009
P0644 Selectivity increment Fishery; Bin8; 2005 * −0.1580 0.2557 −0.6591 0.3431
P0645 Selectivity increment Fishery; Bin9; 2005 * −0.0584 0.2607 −0.5694 0.4527
P0646 Selectivity increment Fishery; Bin10; 2005 * 0.0069 0.2686 −0.5195 0.5333
P0647 Selectivity increment Fishery; Bin11; 2005 * 0.0034 0.2723 −0.5304 0.5371
P0648 Selectivity increment Fishery; Bin12; 2005 * −0.0424 0.2634 −0.5586 0.4738
P0649 Selectivity increment Fishery; Bin1; 2006 * −0.0831 0.4190 −0.9043 0.7381
P0650 Selectivity increment Fishery; Bin2; 2006 * 0.0868 0.3896 −0.6768 0.8504
P0651 Selectivity increment Fishery; Bin3; 2006 * 0.5507 0.3137 −0.0642 1.1655
P0652 Selectivity increment Fishery; Bin4; 2006 * −0.0815 0.2585 −0.5881 0.4251
P0653 Selectivity increment Fishery; Bin5; 2006 * −0.3062 0.2441 −0.7846 0.1723
P0654 Selectivity increment Fishery; Bin6; 2006 * −0.0503 0.2432 −0.5269 0.4264
P0655 Selectivity increment Fishery; Bin7; 2006 * −0.0551 0.2479 −0.5410 0.4308
P0656 Selectivity increment Fishery; Bin8; 2006 * −0.0252 0.2559 −0.5268 0.4763
P0657 Selectivity increment Fishery; Bin9; 2006 * −0.0731 0.2605 −0.5836 0.4375
P0658 Selectivity increment Fishery; Bin10; 2006 * −0.0319 0.2663 −0.5540 0.4901
P0659 Selectivity increment Fishery; Bin11; 2006 * 0.0189 0.2723 −0.5148 0.5526
P0660 Selectivity increment Fishery; Bin12; 2006 * 0.0499 0.2638 −0.4671 0.5670
P0661 Selectivity increment Fishery; Bin1; 2007 * −0.0442 0.4186 −0.8647 0.7763
P0662 Selectivity increment Fishery; Bin2; 2007 * −0.0142 0.3863 −0.7714 0.7429
P0663 Selectivity increment Fishery; Bin3; 2007 * −0.0473 0.3156 −0.6659 0.5713
P0664 Selectivity increment Fishery; Bin4; 2007 * 0.0167 0.2701 −0.5127 0.5461
P0665 Selectivity increment Fishery; Bin5; 2007 * −0.0412 0.2468 −0.5249 0.4425
P0666 Selectivity increment Fishery; Bin6; 2007 * 0.0189 0.2405 −0.4525 0.4904
P0667 Selectivity increment Fishery; Bin7; 2007 * 0.0371 0.2432 −0.4395 0.5138
P0668 Selectivity increment Fishery; Bin8; 2007 * −0.0466 0.2513 −0.5391 0.4459
P0669 Selectivity increment Fishery; Bin9; 2007 * −0.0207 0.2599 −0.5301 0.4886
P0670 Selectivity increment Fishery; Bin10; 2007 * 0.0048 0.2650 −0.5145 0.5241
P0671 Selectivity increment Fishery; Bin11; 2007 * 0.0473 0.2699 −0.4817 0.5762
P0672 Selectivity increment Fishery; Bin12; 2007 * 0.0894 0.2630 −0.4261 0.6048
P0673 Selectivity increment Fishery; Bin1; 2008 * −0.0079 0.4177 −0.8266 0.8108
P0674 Selectivity increment Fishery; Bin2; 2008 * −0.1140 0.3624 −0.8243 0.5962
P0675 Selectivity increment Fishery; Bin3; 2008 * −0.5247 0.3047 −1.1219 0.0724
P0676 Selectivity increment Fishery; Bin4; 2008 * −0.1226 0.2806 −0.6725 0.4274
P0677 Selectivity increment Fishery; Bin5; 2008 * −0.0705 0.2571 −0.5745 0.4335
P0678 Selectivity increment Fishery; Bin6; 2008 * 0.0489 0.2404 −0.4224 0.5201
P0679 Selectivity increment Fishery; Bin7; 2008 * 0.0738 0.2405 −0.3975 0.5452
P0680 Selectivity increment Fishery; Bin8; 2008 * 0.1378 0.2459 −0.3442 0.6198
P0681 Selectivity increment Fishery; Bin9; 2008 * 0.1536 0.2555 −0.3472 0.6544
P0682 Selectivity increment Fishery; Bin10; 2008 * 0.0828 0.2751 −0.4564 0.6220
P0683 Selectivity increment Fishery; Bin11; 2008 * 0.1590 0.2830 −0.3956 0.7137
P0684 Selectivity increment Fishery; Bin12; 2008 * 0.1838 0.2618 −0.3292 0.6969
P0685 Selectivity increment Fishery; Bin1; 2009 * −0.0405 0.4164 −0.8567 0.7757
P0686 Selectivity increment Fishery; Bin2; 2009 * −0.3417 0.3505 −1.0287 0.3453
P0687 Selectivity increment Fishery; Bin3; 2009 * 0.1995 0.2750 −0.3395 0.7385
P0688 Selectivity increment Fishery; Bin4; 2009 * 0.0605 0.2709 −0.4704 0.5914
P0689 Selectivity increment Fishery; Bin5; 2009 * −0.1362 0.2743 −0.6738 0.4015
P0690 Selectivity increment Fishery; Bin6; 2009 * −0.0916 0.2610 −0.6032 0.4199
P0691 Selectivity increment Fishery; Bin7; 2009 * −0.0530 0.2484 −0.5399 0.4339
P0692 Selectivity increment Fishery; Bin8; 2009 * −0.0082 0.2472 −0.4927 0.4763
P0693 Selectivity increment Fishery; Bin9; 2009 * 0.0108 0.2611 −0.5009 0.5224
P0694 Selectivity increment Fishery; Bin10; 2009 * 0.1422 0.2987 −0.4433 0.7277
P0695 Selectivity increment Fishery; Bin11; 2009 * 0.1431 0.2927 −0.4305 0.7167
P0696 Selectivity increment Fishery; Bin12; 2009 * 0.1152 0.2631 −0.4006 0.6309
P0697 Selectivity increment Fishery; Bin1; 2010 * 0.0380 0.4155 −0.7764 0.8524
P0698 Selectivity increment Fishery; Bin2; 2010 * 0.0713 0.3478 −0.6103 0.7529
P0699 Selectivity increment Fishery; Bin3; 2010 * −0.6053 0.2855 −1.1648 −0.0458
P0700 Selectivity increment Fishery; Bin4; 2010 * 0.4401 0.2487 −0.0475 0.9276
P0701 Selectivity increment Fishery; Bin5; 2010 * 0.1763 0.2702 −0.3533 0.7059
P0702 Selectivity increment Fishery; Bin6; 2010 * −0.2436 0.2851 −0.8024 0.3152
P0703 Selectivity increment Fishery; Bin7; 2010 * −0.0793 0.2864 −0.6407 0.4821
P0704 Selectivity increment Fishery; Bin8; 2010 * 0.0697 0.2604 −0.4407 0.5800
P0705 Selectivity increment Fishery; Bin9; 2010 * 0.0800 0.2622 −0.4339 0.5940
P0706 Selectivity increment Fishery; Bin10; 2010 * 0.0262 0.2937 −0.5494 0.6018
P0707 Selectivity increment Fishery; Bin11; 2010 * −0.0324 0.2989 −0.6181 0.5533
P0708 Selectivity increment Fishery; Bin12; 2010 * 0.0589 0.2752 −0.4806 0.5984
P0709 Selectivity increment Fishery; Bin1; 2011 * 0.0295 0.4160 −0.7858 0.8448
P0710 Selectivity increment Fishery; Bin2; 2011 * −0.0180 0.3414 −0.6872 0.6511
P0711 Selectivity increment Fishery; Bin3; 2011 * 0.0445 0.2837 −0.5116 0.6005
P0712 Selectivity increment Fishery; Bin4; 2011 * −1.0769 0.2551 −1.5769 −0.5770
P0713 Selectivity increment Fishery; Bin5; 2011 * 0.4190 0.2469 −0.0649 0.9030
P0714 Selectivity increment Fishery; Bin6; 2011 * 0.3585 0.2725 −0.1757 0.8927
P0715 Selectivity increment Fishery; Bin7; 2011 * 0.1392 0.2841 −0.4176 0.6961
P0716 Selectivity increment Fishery; Bin8; 2011 * −0.0029 0.2677 −0.5275 0.5217
P0717 Selectivity increment Fishery; Bin9; 2011 * 0.0017 0.2713 −0.5299 0.5334
P0718 Selectivity increment Fishery; Bin10; 2011 * 0.0820 0.2732 −0.4534 0.6174
P0719 Selectivity increment Fishery; Bin11; 2011 * 0.0533 0.2812 −0.4978 0.6044
P0720 Selectivity increment Fishery; Bin12; 2011 * −0.0299 0.2765 −0.5719 0.5121
P0721 Selectivity increment Fishery; Bin1; 2012 * −0.0139 0.4163 −0.8298 0.8021
P0722 Selectivity increment Fishery; Bin2; 2012 * 0.2336 0.3613 −0.4745 0.9417
P0723 Selectivity increment Fishery; Bin3; 2012 * 0.1890 0.2724 −0.3450 0.7229
P0724 Selectivity increment Fishery; Bin4; 2012 * 0.6247 0.2561 0.1228 1.1266
P0725 Selectivity increment Fishery; Bin5; 2012 * −1.0798 0.2559 −1.5813 −0.5782
P0726 Selectivity increment Fishery; Bin6; 2012 * −0.0236 0.2490 −0.5115 0.4644
P0727 Selectivity increment Fishery; Bin7; 2012 * 0.0121 0.2637 −0.5047 0.5289
P0728 Selectivity increment Fishery; Bin8; 2012 * 0.0237 0.2771 −0.5194 0.5668
P0729 Selectivity increment Fishery; Bin9; 2012 * 0.0051 0.2797 −0.5432 0.5533
P0730 Selectivity increment Fishery; Bin10; 2012 * −0.0627 0.2976 −0.6459 0.5205
P0731 Selectivity increment Fishery; Bin11; 2012 * 0.0107 0.3307 −0.6375 0.6590
P0732 Selectivity increment Fishery; Bin12; 2012 * 0.0811 0.2825 −0.4726 0.6347
P0733 Selectivity increment Fishery; Bin1; 2013 * 0.0205 0.4165 −0.7958 0.8368
P0734 Selectivity increment Fishery; Bin2; 2013 * −0.1915 0.3668 −0.9104 0.5275
P0735 Selectivity increment Fishery; Bin3; 2013 * 0.0270 0.2910 −0.5434 0.5974
P0736 Selectivity increment Fishery; Bin4; 2013 * −0.1384 0.2482 −0.6249 0.3481
P0737 Selectivity increment Fishery; Bin5; 2013 * 0.5116 0.2562 0.0094 1.0138
P0738 Selectivity increment Fishery; Bin6; 2013 * −0.6014 0.2588 −1.1087 −0.0941
P0739 Selectivity increment Fishery; Bin7; 2013 * −0.1571 0.2700 −0.6863 0.3720
P0740 Selectivity increment Fishery; Bin8; 2013 * 0.0768 0.3021 −0.5153 0.6688
P0741 Selectivity increment Fishery; Bin9; 2013 * 0.1177 0.2916 −0.4538 0.6892
P0742 Selectivity increment Fishery; Bin10; 2013 * 0.1362 0.2948 −0.4415 0.7139
P0743 Selectivity increment Fishery; Bin11; 2013 * 0.1077 0.3419 −0.5625 0.7778
P0744 Selectivity increment Fishery; Bin12; 2013 * 0.0911 0.2877 −0.4728 0.6550
P0745 Selectivity increment Fishery; Bin1; 2014 * −0.0208 0.4159 −0.8359 0.7943
P0746 Selectivity increment Fishery; Bin2; 2014 * 0.1368 0.3573 −0.5635 0.8372
P0747 Selectivity increment Fishery; Bin3; 2014 * −0.0265 0.3022 −0.6189 0.5659
P0748 Selectivity increment Fishery; Bin4; 2014 * −0.1390 0.2622 −0.6529 0.3749
P0749 Selectivity increment Fishery; Bin5; 2014 * −0.0989 0.2478 −0.5845 0.3868
P0750 Selectivity increment Fishery; Bin6; 2014 * 0.3036 0.2553 −0.1967 0.8038
P0751 Selectivity increment Fishery; Bin7; 2014 * 0.1480 0.2667 −0.3747 0.6708
P0752 Selectivity increment Fishery; Bin8; 2014 * −0.1281 0.2924 −0.7011 0.4449
P0753 Selectivity increment Fishery; Bin9; 2014 * −0.1334 0.3287 −0.7777 0.5110
P0754 Selectivity increment Fishery; Bin10; 2014 * −0.0146 0.3099 −0.6219 0.5927
P0755 Selectivity increment Fishery; Bin11; 2014 * −0.0181 0.3208 −0.6467 0.6106
P0756 Selectivity increment Fishery; Bin12; 2014 * −0.0092 0.2918 −0.5810 0.5627
P0757 Selectivity increment Fishery; Bin1; 2015 * −0.0049 0.4173 −0.8228 0.8129
P0758 Selectivity increment Fishery; Bin2; 2015 * −0.4664 0.3403 −1.1335 0.2006
P0759 Selectivity increment Fishery; Bin3; 2015 * 1.0864 0.2825 0.5327 1.6401
P0760 Selectivity increment Fishery; Bin4; 2015 * 0.1881 0.2654 −0.3321 0.7083
P0761 Selectivity increment Fishery; Bin5; 2015 * −0.1869 0.2562 −0.6890 0.3151
P0762 Selectivity increment Fishery; Bin6; 2015 * −0.1074 0.2478 −0.5930 0.3783
P0763 Selectivity increment Fishery; Bin7; 2015 * −0.1479 0.2510 −0.6399 0.3441
P0764 Selectivity increment Fishery; Bin8; 2015 * −0.1207 0.2715 −0.6527 0.4113
P0765 Selectivity increment Fishery; Bin9; 2015 * −0.1278 0.3310 −0.7765 0.5209
P0766 Selectivity increment Fishery; Bin10; 2015 * −0.0646 0.3500 −0.7505 0.6213
P0767 Selectivity increment Fishery; Bin11; 2015 * −0.0234 0.3684 −0.7454 0.6986
P0768 Selectivity increment Fishery; Bin12; 2015 * −0.0245 0.2928 −0.5983 0.5493
P0769 Selectivity increment Fishery; Bin1; 2016 * 0.0709 0.4184 −0.7491 0.8909
P0770 Selectivity increment Fishery; Bin2; 2016 * 0.0205 0.3679 −0.7006 0.7417
P0771 Selectivity increment Fishery; Bin3; 2016 * −1.4595 0.2654 −1.9797 −0.9393
P0772 Selectivity increment Fishery; Bin4; 2016 * 1.0623 0.2498 0.5726 1.5519
P0773 Selectivity increment Fishery; Bin5; 2016 * 0.2840 0.2593 −0.2243 0.7922
P0774 Selectivity increment Fishery; Bin6; 2016 * −0.0027 0.2623 −0.5167 0.5114
P0775 Selectivity increment Fishery; Bin7; 2016 * −0.0982 0.2597 −0.6071 0.4107
P0776 Selectivity increment Fishery; Bin8; 2016 * 0.2058 0.2624 −0.3085 0.7201
P0777 Selectivity increment Fishery; Bin9; 2016 * 0.1100 0.3019 −0.4817 0.7018
P0778 Selectivity increment Fishery; Bin10; 2016 * −0.0858 0.3388 −0.7498 0.5782
P0779 Selectivity increment Fishery; Bin11; 2016 * −0.0413 0.3728 −0.7720 0.6894
P0780 Selectivity increment Fishery; Bin12; 2016 * −0.0660 0.2958 −0.6458 0.5138
P0781 Selectivity increment Fishery; Bin1; 2017 * 0.0527 0.4179 −0.7664 0.8719
P0782 Selectivity increment Fishery; Bin2; 2017 * 0.2806 0.3829 −0.4698 1.0311
P0783 Selectivity increment Fishery; Bin3; 2017 * −0.2525 0.3120 −0.8641 0.3590
P0784 Selectivity increment Fishery; Bin4; 2017 * −1.1177 0.2428 −1.5936 −0.6418
P0785 Selectivity increment Fishery; Bin5; 2017 * 0.5963 0.2497 0.1068 1.0857
P0786 Selectivity increment Fishery; Bin6; 2017 * 0.3303 0.2619 −0.1831 0.8436
P0787 Selectivity increment Fishery; Bin7; 2017 * 0.1867 0.2691 −0.3407 0.7141
P0788 Selectivity increment Fishery; Bin8; 2017 * −0.0775 0.2733 −0.6132 0.4583
P0789 Selectivity increment Fishery; Bin9; 2017 * 0.0698 0.2694 −0.4582 0.5978
P0790 Selectivity increment Fishery; Bin10; 2017 * 0.0476 0.2886 −0.5180 0.6133
P0791 Selectivity increment Fishery; Bin11; 2017 * −0.0586 0.3038 −0.6541 0.5369
P0792 Selectivity increment Fishery; Bin12; 2017 * −0.0577 0.2800 −0.6065 0.4910
P0793 Selectivity increment Fishery; Bin1; 2018 * 0.0269 0.4176 −0.7916 0.8454
P0794 Selectivity increment Fishery; Bin2; 2018 * 0.3297 0.3844 −0.4237 1.0831
P0795 Selectivity increment Fishery; Bin3; 2018 * 0.1383 0.3454 −0.5386 0.8153
P0796 Selectivity increment Fishery; Bin4; 2018 * −0.5920 0.2685 −1.1182 −0.0658
P0797 Selectivity increment Fishery; Bin5; 2018 * 0.0098 0.2416 −0.4637 0.4833
P0798 Selectivity increment Fishery; Bin6; 2018 * 0.1787 0.2486 −0.3085 0.6660
P0799 Selectivity increment Fishery; Bin7; 2018 * 0.1098 0.2599 −0.3996 0.6191
P0800 Selectivity increment Fishery; Bin8; 2018 * 0.0802 0.2732 −0.4553 0.6156
P0801 Selectivity increment Fishery; Bin9; 2018 * −0.0363 0.2658 −0.5572 0.4847
P0802 Selectivity increment Fishery; Bin10; 2018 * −0.0785 0.2671 −0.6021 0.4451
P0803 Selectivity increment Fishery; Bin11; 2018 * −0.0815 0.2758 −0.6221 0.4591
P0804 Selectivity increment Fishery; Bin12; 2018 * −0.0851 0.2740 −0.6221 0.4518
P0805 Selectivity increment Fishery; Bin1; 2019 * 0.0466 0.4171 −0.7710 0.8641
P0806 Selectivity increment Fishery; Bin2; 2019 * 0.4753 0.3768 −0.2631 1.2138
P0807 Selectivity increment Fishery; Bin3; 2019 * 0.2133 0.3498 −0.4724 0.8989
P0808 Selectivity increment Fishery; Bin4; 2019 * −0.3828 0.3044 −0.9794 0.2138
P0809 Selectivity increment Fishery; Bin5; 2019 * −1.2476 0.2535 −1.7444 −0.7507
P0810 Selectivity increment Fishery; Bin6; 2019 * 0.0949 0.2440 −0.3833 0.5732
P0811 Selectivity increment Fishery; Bin7; 2019 * 0.4408 0.2500 −0.0491 0.9307
P0812 Selectivity increment Fishery; Bin8; 2019 * 0.2212 0.2554 −0.2793 0.7217
P0813 Selectivity increment Fishery; Bin9; 2019 * 0.1280 0.2577 −0.3771 0.6332
P0814 Selectivity increment Fishery; Bin10; 2019 * 0.1319 0.2624 −0.3825 0.6463
P0815 Selectivity increment Fishery; Bin11; 2019 * −0.0475 0.2710 −0.5786 0.4836
P0816 Selectivity increment Fishery; Bin12; 2019 * −0.0742 0.2705 −0.6044 0.4561
P0817 Selectivity increment Fishery; Bin1; 2020 * −0.0191 0.4206 −0.8434 0.8052
P0818 Selectivity increment Fishery; Bin2; 2020 * 0.6177 0.3313 −0.0316 1.2671
P0819 Selectivity increment Fishery; Bin3; 2020 * 0.4207 0.3273 −0.2208 1.0622
P0820 Selectivity increment Fishery; Bin4; 2020 * 0.5413 0.3105 −0.0673 1.1498
P0821 Selectivity increment Fishery; Bin5; 2020 * 0.1307 0.2757 −0.4096 0.6709
P0822 Selectivity increment Fishery; Bin6; 2020 * −0.4191 0.2437 −0.8968 0.0586
P0823 Selectivity increment Fishery; Bin7; 2020 * −0.5005 0.2439 −0.9786 −0.0224
P0824 Selectivity increment Fishery; Bin8; 2020 * −0.4159 0.2603 −0.9260 0.0942
P0825 Selectivity increment Fishery; Bin9; 2020 * −0.1799 0.2700 −0.7091 0.3493
P0826 Selectivity increment Fishery; Bin10; 2020 * −0.1332 0.2641 −0.6509 0.3844
P0827 Selectivity increment Fishery; Bin11; 2020 * 0.0035 0.2686 −0.5231 0.5300
P0828 Selectivity increment Fishery; Bin12; 2020 * −0.0460 0.2683 −0.5718 0.4798
P0829 Selectivity increment Fishery; Bin1; 2021 * −0.0184 0.4212 −0.8439 0.8071
P0830 Selectivity increment Fishery; Bin2; 2021 * 0.3251 0.2749 −0.2138 0.8639
P0831 Selectivity increment Fishery; Bin3; 2021 * 0.9147 0.2699 0.3857 1.4437
P0832 Selectivity increment Fishery; Bin4; 2021 * −0.1532 0.2838 −0.7093 0.4030
P0833 Selectivity increment Fishery; Bin5; 2021 * −0.0152 0.2871 −0.5779 0.5474
P0834 Selectivity increment Fishery; Bin6; 2021 * −0.6384 0.2690 −1.1655 −0.1113
P0835 Selectivity increment Fishery; Bin7; 2021 * −0.1600 0.2500 −0.6500 0.3299
P0836 Selectivity increment Fishery; Bin8; 2021 * 0.0909 0.2552 −0.4093 0.5910
P0837 Selectivity increment Fishery; Bin9; 2021 * −0.1014 0.2714 −0.6334 0.4305
P0838 Selectivity increment Fishery; Bin10; 2021 * −0.1057 0.2667 −0.6285 0.4170
P0839 Selectivity increment Fishery; Bin11; 2021 * −0.0815 0.2704 −0.6114 0.4484
P0840 Selectivity increment Fishery; Bin12; 2021 * −0.0567 0.2670 −0.5800 0.4666
P0841 Selectivity increment Fishery; Bin1; 2022 * 0.0125 0.4227 −0.8160 0.8411
P0842 Selectivity increment Fishery; Bin2; 2022 * 0.2365 0.3079 −0.3670 0.8399
P0843 Selectivity increment Fishery; Bin3; 2022 * −0.4506 0.2537 −0.9478 0.0466
P0844 Selectivity increment Fishery; Bin4; 2022 * 0.5723 0.2483 0.0856 1.0591
P0845 Selectivity increment Fishery; Bin5; 2022 * 0.0776 0.2801 −0.4714 0.6266
P0846 Selectivity increment Fishery; Bin6; 2022 * 0.0682 0.2955 −0.5109 0.6473
P0847 Selectivity increment Fishery; Bin7; 2022 * −0.2542 0.2823 −0.8076 0.2991
P0848 Selectivity increment Fishery; Bin8; 2022 * −0.0369 0.2568 −0.5401 0.4664
P0849 Selectivity increment Fishery; Bin9; 2022 * −0.0857 0.2572 −0.5898 0.4184
P0850 Selectivity increment Fishery; Bin10; 2022 * −0.1450 0.2819 −0.6976 0.4076
P0851 Selectivity increment Fishery; Bin11; 2022 * −0.0111 0.2962 −0.5915 0.5694
P0852 Selectivity increment Fishery; Bin12; 2022 * 0.0163 0.2718 −0.5165 0.5491
P0853 Selectivity increment Fishery; Bin1; 2023 * 0.0335 0.4240 −0.7975 0.8646
P0854 Selectivity increment Fishery; Bin2; 2023 * −0.5536 0.3485 −1.2367 0.1295
P0855 Selectivity increment Fishery; Bin3; 2023 * 0.1024 0.3004 −0.4864 0.6911
P0856 Selectivity increment Fishery; Bin4; 2023 * −0.1481 0.2631 −0.6638 0.3677
P0857 Selectivity increment Fishery; Bin5; 2023 * 0.5445 0.2616 0.0319 1.0572
P0858 Selectivity increment Fishery; Bin6; 2023 * 0.3275 0.2881 −0.2372 0.8923
P0859 Selectivity increment Fishery; Bin7; 2023 * −0.1214 0.2972 −0.7039 0.4612
P0860 Selectivity increment Fishery; Bin8; 2023 * −0.2840 0.3093 −0.8901 0.3222
P0861 Selectivity increment Fishery; Bin9; 2023 * 0.0082 0.2801 −0.5408 0.5572
P0862 Selectivity increment Fishery; Bin10; 2023 * 0.0548 0.2938 −0.5211 0.6307
P0863 Selectivity increment Fishery; Bin11; 2023 * 0.0069 0.3066 −0.5941 0.6079
P0864 Selectivity increment Fishery; Bin12; 2023 * 0.0292 0.2763 −0.5124 0.5707
P0865 Selectivity increment Fishery; Bin1; 2024 * 0.0203 0.4247 −0.8122 0.8528
P0866 Selectivity increment Fishery; Bin2; 2024 * −0.5495 0.3664 −1.2676 0.1685
P0867 Selectivity increment Fishery; Bin3; 2024 * 0.1606 0.3170 −0.4607 0.7819
P0868 Selectivity increment Fishery; Bin4; 2024 * 0.1045 0.2938 −0.4713 0.6804
P0869 Selectivity increment Fishery; Bin5; 2024 * −0.2087 0.2602 −0.7186 0.3012
P0870 Selectivity increment Fishery; Bin6; 2024 * 0.3659 0.2595 −0.1427 0.8745
P0871 Selectivity increment Fishery; Bin7; 2024 * 0.2160 0.2755 −0.3239 0.7559
P0872 Selectivity increment Fishery; Bin8; 2024 * −0.0331 0.3171 −0.6545 0.5884
P0873 Selectivity increment Fishery; Bin9; 2024 * −0.0209 0.2958 −0.6007 0.5589
P0874 Selectivity increment Fishery; Bin10; 2024 * −0.0052 0.2983 −0.5898 0.5795
P0875 Selectivity increment Fishery; Bin11; 2024 * −0.0403 0.3419 −0.7104 0.6298
P0876 Selectivity increment Fishery; Bin12; 2024 * −0.0097 0.2891 −0.5763 0.5569
P0877 Selectivity increment Fishery; Bin1; 2025 * 0.0465 0.4277 −0.7917 0.8847
P0878 Selectivity increment Fishery; Bin2; 2025 * −0.1805 0.3689 −0.9034 0.5425
P0879 Selectivity increment Fishery; Bin3; 2025 * −0.3735 0.3337 −1.0275 0.2805
P0880 Selectivity increment Fishery; Bin4; 2025 * −0.1775 0.3158 −0.7964 0.4414
P0881 Selectivity increment Fishery; Bin5; 2025 * −0.2383 0.2955 −0.8174 0.3409
P0882 Selectivity increment Fishery; Bin6; 2025 * 0.1600 0.2522 −0.3343 0.6542
P0883 Selectivity increment Fishery; Bin7; 2025 * 0.3901 0.2527 −0.1051 0.8854
P0884 Selectivity increment Fishery; Bin8; 2025 * 0.2710 0.2754 −0.2687 0.8107
P0885 Selectivity increment Fishery; Bin9; 2025 * 0.0724 0.2890 −0.4940 0.6388
P0886 Selectivity increment Fishery; Bin10; 2025 * 0.0628 0.2921 −0.5098 0.6354
P0887 Selectivity increment Fishery; Bin11; 2025 * −0.0233 0.3339 −0.6777 0.6312
P0888 Selectivity increment Fishery; Bin12; 2025 * −0.0097 0.2915 −0.5811 0.5617
P0889 Selectivity increment Fishery; Bin1; 2026 * 0.0057 0.4326 −0.8422 0.8537
P0890 Selectivity increment Fishery; Bin2; 2026 * −0.0131 0.4291 −0.8541 0.8278
P0891 Selectivity increment Fishery; Bin3; 2026 * 0.0024 0.4306 −0.8416 0.8464
P0892 Selectivity increment Fishery; Bin4; 2026 * 0.0136 0.4330 −0.8351 0.8622
P0893 Selectivity increment Fishery; Bin5; 2026 * 0.0458 0.4381 −0.8128 0.9045
P0894 Selectivity increment Fishery; Bin6; 2026 * −0.1266 0.3089 −0.7320 0.4787
P0895 Selectivity increment Fishery; Bin7; 2026 * −0.1276 0.2822 −0.6807 0.4256
P0896 Selectivity increment Fishery; Bin8; 2026 * 0.0580 0.2800 −0.4908 0.6068
P0897 Selectivity increment Fishery; Bin9; 2026 * 0.0408 0.2804 −0.5087 0.5903
P0898 Selectivity increment Fishery; Bin10; 2026 * 0.0264 0.2850 −0.5322 0.5850
P0899 Selectivity increment Fishery; Bin11; 2026 * 0.0629 0.3040 −0.5330 0.6587
P0900 Selectivity increment Fishery; Bin12; 2026 * 0.0118 0.2926 −0.5617 0.5853
P0901 Selectivity increment AVO; Bin2; 1994 * 0.4268 0.3221 −0.2045 1.0581
P0902 Selectivity increment AVO; Bin3; 1994 * 0.2014 0.3578 −0.4998 0.9027
P0903 Selectivity increment AVO; Bin4; 1994 * 0.0307 0.3479 −0.6511 0.7125
P0904 Selectivity increment AVO; Bin5; 1994 * 0.1390 0.3399 −0.5273 0.8052
P0905 Selectivity increment AVO; Bin6; 1994 * 0.1843 0.3570 −0.5154 0.8839
P0906 Selectivity increment AVO; Bin7; 1994 * −0.2044 0.3577 −0.9055 0.4967
P0907 Selectivity increment AVO; Bin8; 1994 * 0.0739 0.3182 −0.5498 0.6976
P0908 Selectivity increment AVO; Bin2; 1995 * 0.2193 0.2842 −0.3376 0.7763
P0909 Selectivity increment AVO; Bin3; 1995 * 0.2252 0.2938 −0.3507 0.8010
P0910 Selectivity increment AVO; Bin4; 1995 * 0.1966 0.2925 −0.3766 0.7699
P0911 Selectivity increment AVO; Bin5; 1995 * 0.1891 0.2912 −0.3817 0.7599
P0912 Selectivity increment AVO; Bin6; 1995 * 0.2052 0.2922 −0.3676 0.7779
P0913 Selectivity increment AVO; Bin7; 1995 * 0.2084 0.2921 −0.3640 0.7808
P0914 Selectivity increment AVO; Bin8; 1995 * 0.2116 0.2641 −0.3061 0.7293
P0915 Selectivity increment AVO; Bin2; 1996 * 0.2181 0.2742 −0.3193 0.7556
P0916 Selectivity increment AVO; Bin3; 1996 * 0.2133 0.2742 −0.3240 0.7507
P0917 Selectivity increment AVO; Bin4; 1996 * 0.2070 0.2725 −0.3271 0.7412
P0918 Selectivity increment AVO; Bin5; 1996 * 0.1986 0.2723 −0.3351 0.7323
P0919 Selectivity increment AVO; Bin6; 1996 * 0.2015 0.2730 −0.3335 0.7364
P0920 Selectivity increment AVO; Bin7; 1996 * 0.2067 0.2721 −0.3266 0.7400
P0921 Selectivity increment AVO; Bin8; 1996 * 0.2151 0.2472 −0.2694 0.6997
P0922 Selectivity increment AVO; Bin2; 1997 * 0.2620 0.2631 −0.2535 0.7776
P0923 Selectivity increment AVO; Bin3; 1997 * 0.2517 0.2607 −0.2594 0.7627
P0924 Selectivity increment AVO; Bin4; 1997 * 0.2206 0.2594 −0.2877 0.7289
P0925 Selectivity increment AVO; Bin5; 1997 * 0.2321 0.2585 −0.2745 0.7387
P0926 Selectivity increment AVO; Bin6; 1997 * 0.2202 0.2597 −0.2888 0.7292
P0927 Selectivity increment AVO; Bin7; 1997 * 0.2254 0.2590 −0.2822 0.7331
P0928 Selectivity increment AVO; Bin8; 1997 * 0.2178 0.2340 −0.2408 0.6764
P0929 Selectivity increment AVO; Bin2; 1998 * 0.2201 0.2506 −0.2710 0.7112
P0930 Selectivity increment AVO; Bin3; 1998 * 0.2988 0.2509 −0.1930 0.7905
P0931 Selectivity increment AVO; Bin4; 1998 * 0.2887 0.2506 −0.2025 0.7799
P0932 Selectivity increment AVO; Bin5; 1998 * 0.2513 0.2507 −0.2401 0.7427
P0933 Selectivity increment AVO; Bin6; 1998 * 0.2567 0.2509 −0.2351 0.7485
P0934 Selectivity increment AVO; Bin7; 1998 * 0.2612 0.2497 −0.2283 0.7507
P0935 Selectivity increment AVO; Bin8; 1998 * 0.2331 0.2239 −0.2057 0.6719
P0936 Selectivity increment AVO; Bin2; 1999 * 0.2312 0.2468 −0.2526 0.7149
P0937 Selectivity increment AVO; Bin3; 1999 * 0.3187 0.2435 −0.1584 0.7959
P0938 Selectivity increment AVO; Bin4; 1999 * 0.3135 0.2427 −0.1622 0.7891
P0939 Selectivity increment AVO; Bin5; 1999 * 0.2774 0.2435 −0.1999 0.7547
P0940 Selectivity increment AVO; Bin6; 1999 * 0.2693 0.2437 −0.2083 0.7470
P0941 Selectivity increment AVO; Bin7; 1999 * 0.2849 0.2420 −0.1894 0.7593
P0942 Selectivity increment AVO; Bin8; 1999 * 0.2551 0.2166 −0.1694 0.6796
P0943 Selectivity increment AVO; Bin2; 2000 * 0.2540 0.2396 −0.2156 0.7236
P0944 Selectivity increment AVO; Bin3; 2000 * 0.2719 0.2393 −0.1972 0.7410
P0945 Selectivity increment AVO; Bin4; 2000 * 0.3283 0.2384 −0.1390 0.7955
P0946 Selectivity increment AVO; Bin5; 2000 * 0.2944 0.2392 −0.1744 0.7632
P0947 Selectivity increment AVO; Bin6; 2000 * 0.2994 0.2398 −0.1707 0.7694
P0948 Selectivity increment AVO; Bin7; 2000 * 0.2678 0.2390 −0.2007 0.7363
P0949 Selectivity increment AVO; Bin8; 2000 * 0.2747 0.2126 −0.1419 0.6913
P0950 Selectivity increment AVO; Bin2; 2001 * 0.3133 0.2345 −0.1463 0.7729
P0951 Selectivity increment AVO; Bin3; 2001 * 0.3023 0.2373 −0.1628 0.7673
P0952 Selectivity increment AVO; Bin4; 2001 * 0.2844 0.2370 −0.1800 0.7489
P0953 Selectivity increment AVO; Bin5; 2001 * 0.3131 0.2372 −0.1517 0.7780
P0954 Selectivity increment AVO; Bin6; 2001 * 0.3172 0.2374 −0.1480 0.7824
P0955 Selectivity increment AVO; Bin7; 2001 * 0.2960 0.2370 −0.1685 0.7605
P0956 Selectivity increment AVO; Bin8; 2001 * 0.2805 0.2102 −0.1314 0.6925
P0957 Selectivity increment AVO; Bin2; 2002 * 0.3008 0.2355 −0.1608 0.7625
P0958 Selectivity increment AVO; Bin3; 2002 * 0.3180 0.2342 −0.1411 0.7771
P0959 Selectivity increment AVO; Bin4; 2002 * 0.3056 0.2342 −0.1533 0.7645
P0960 Selectivity increment AVO; Bin5; 2002 * 0.3188 0.2346 −0.1410 0.7786
P0961 Selectivity increment AVO; Bin6; 2002 * 0.3244 0.2345 −0.1353 0.7840
P0962 Selectivity increment AVO; Bin7; 2002 * 0.3085 0.2345 −0.1510 0.7680
P0963 Selectivity increment AVO; Bin8; 2002 * 0.2908 0.2078 −0.1165 0.6980
P0964 Selectivity increment AVO; Bin2; 2003 * 0.2507 0.2309 −0.2019 0.7033
P0965 Selectivity increment AVO; Bin3; 2003 * 0.2393 0.2357 −0.2227 0.7013
P0966 Selectivity increment AVO; Bin4; 2003 * 0.3117 0.2351 −0.1490 0.7725
P0967 Selectivity increment AVO; Bin5; 2003 * 0.3291 0.2351 −0.1317 0.7898
P0968 Selectivity increment AVO; Bin6; 2003 * 0.3118 0.2353 −0.1493 0.7729
P0969 Selectivity increment AVO; Bin7; 2003 * 0.3008 0.2349 −0.1597 0.7612
P0970 Selectivity increment AVO; Bin8; 2003 * 0.3001 0.2080 −0.1075 0.7077
P0971 Selectivity increment AVO; Bin2; 2004 * 0.2241 0.2342 −0.2349 0.6830
P0972 Selectivity increment AVO; Bin3; 2004 * 0.2365 0.2351 −0.2244 0.6973
P0973 Selectivity increment AVO; Bin4; 2004 * 0.3237 0.2336 −0.1342 0.7816
P0974 Selectivity increment AVO; Bin5; 2004 * 0.3248 0.2340 −0.1338 0.7835
P0975 Selectivity increment AVO; Bin6; 2004 * 0.3064 0.2345 −0.1533 0.7661
P0976 Selectivity increment AVO; Bin7; 2004 * 0.2994 0.2344 −0.1600 0.7588
P0977 Selectivity increment AVO; Bin8; 2004 * 0.2971 0.2078 −0.1101 0.7043
P0978 Selectivity increment AVO; Bin2; 2005 * 0.3122 0.2340 −0.1465 0.7708
P0979 Selectivity increment AVO; Bin3; 2005 * 0.2707 0.2370 −0.1939 0.7353
P0980 Selectivity increment AVO; Bin4; 2005 * 0.2088 0.2361 −0.2539 0.6714
P0981 Selectivity increment AVO; Bin5; 2005 * 0.2422 0.2355 −0.2193 0.7037
P0982 Selectivity increment AVO; Bin6; 2005 * 0.2737 0.2355 −0.1878 0.7352
P0983 Selectivity increment AVO; Bin7; 2005 * 0.2837 0.2354 −0.1776 0.7450
P0984 Selectivity increment AVO; Bin8; 2005 * 0.2886 0.2091 −0.1212 0.6985
P0985 Selectivity increment AVO; Bin2; 2006 * 0.2699 0.2375 −0.1956 0.7355
P0986 Selectivity increment AVO; Bin3; 2006 * 0.2465 0.2377 −0.2194 0.7124
P0987 Selectivity increment AVO; Bin4; 2006 * 0.2044 0.2360 −0.2583 0.6670
P0988 Selectivity increment AVO; Bin5; 2006 * 0.2238 0.2353 −0.2374 0.6850
P0989 Selectivity increment AVO; Bin6; 2006 * 0.2520 0.2353 −0.2091 0.7131
P0990 Selectivity increment AVO; Bin7; 2006 * 0.2653 0.2354 −0.1961 0.7267
P0991 Selectivity increment AVO; Bin8; 2006 * 0.2690 0.2100 −0.1426 0.6806
P0992 Selectivity increment AVO; Bin2; 2007 * 0.2692 0.2368 −0.1949 0.7332
P0993 Selectivity increment AVO; Bin3; 2007 * 0.2569 0.2368 −0.2071 0.7210
P0994 Selectivity increment AVO; Bin4; 2007 * 0.2281 0.2359 −0.2343 0.6904
P0995 Selectivity increment AVO; Bin5; 2007 * 0.2419 0.2351 −0.2189 0.7027
P0996 Selectivity increment AVO; Bin6; 2007 * 0.2516 0.2350 −0.2090 0.7122
P0997 Selectivity increment AVO; Bin7; 2007 * 0.2401 0.2350 −0.2206 0.7008
P0998 Selectivity increment AVO; Bin8; 2007 * 0.2437 0.2092 −0.1664 0.6538
P0999 Selectivity increment AVO; Bin2; 2008 * 0.2695 0.2362 −0.1933 0.7324
P1000 Selectivity increment AVO; Bin3; 2008 * 0.2401 0.2375 −0.2253 0.7055
P1001 Selectivity increment AVO; Bin4; 2008 * 0.1914 0.2376 −0.2743 0.6571
P1002 Selectivity increment AVO; Bin5; 2008 * 0.1803 0.2377 −0.2856 0.6462
P1003 Selectivity increment AVO; Bin6; 2008 * 0.1896 0.2375 −0.2758 0.6551
P1004 Selectivity increment AVO; Bin7; 2008 * 0.2055 0.2371 −0.2592 0.6702
P1005 Selectivity increment AVO; Bin8; 2008 * 0.2248 0.2109 −0.1886 0.6382
P1006 Selectivity increment AVO; Bin2; 2009 * 0.2256 0.2352 −0.2354 0.6867
P1007 Selectivity increment AVO; Bin3; 2009 * 0.2164 0.2381 −0.2503 0.6832
P1008 Selectivity increment AVO; Bin4; 2009 * 0.1855 0.2380 −0.2810 0.6519
P1009 Selectivity increment AVO; Bin5; 2009 * 0.1817 0.2386 −0.2860 0.6494
P1010 Selectivity increment AVO; Bin6; 2009 * 0.1921 0.2389 −0.2761 0.6602
P1011 Selectivity increment AVO; Bin7; 2009 * 0.2021 0.2383 −0.2650 0.6692
P1012 Selectivity increment AVO; Bin8; 2009 * 0.2012 0.2114 −0.2132 0.6156
P1013 Selectivity increment AVO; Bin2; 2010 * 0.2367 0.2353 −0.2245 0.6979
P1014 Selectivity increment AVO; Bin3; 2010 * 0.1889 0.2390 −0.2795 0.6574
P1015 Selectivity increment AVO; Bin4; 2010 * 0.2100 0.2375 −0.2554 0.6754
P1016 Selectivity increment AVO; Bin5; 2010 * 0.1807 0.2382 −0.2861 0.6476
P1017 Selectivity increment AVO; Bin6; 2010 * 0.1855 0.2386 −0.2821 0.6531
P1018 Selectivity increment AVO; Bin7; 2010 * 0.1926 0.2382 −0.2742 0.6595
P1019 Selectivity increment AVO; Bin8; 2010 * 0.1823 0.2112 −0.2316 0.5962
P1020 Selectivity increment AVO; Bin2; 2011 * 0.2198 0.2349 −0.2407 0.6802
P1021 Selectivity increment AVO; Bin3; 2011 * 0.1828 0.2393 −0.2863 0.6519
P1022 Selectivity increment AVO; Bin4; 2011 * 0.1560 0.2379 −0.3103 0.6223
P1023 Selectivity increment AVO; Bin5; 2011 * 0.1683 0.2383 −0.2987 0.6354
P1024 Selectivity increment AVO; Bin6; 2011 * 0.1801 0.2385 −0.2872 0.6475
P1025 Selectivity increment AVO; Bin7; 2011 * 0.1860 0.2383 −0.2810 0.6531
P1026 Selectivity increment AVO; Bin8; 2011 * 0.1717 0.2116 −0.2430 0.5863
P1027 Selectivity increment AVO; Bin2; 2012 * 0.2201 0.2381 −0.2465 0.6868
P1028 Selectivity increment AVO; Bin3; 2012 * 0.1874 0.2380 −0.2791 0.6539
P1029 Selectivity increment AVO; Bin4; 2012 * 0.1557 0.2357 −0.3062 0.6177
P1030 Selectivity increment AVO; Bin5; 2012 * 0.1715 0.2374 −0.2937 0.6367
P1031 Selectivity increment AVO; Bin6; 2012 * 0.1797 0.2375 −0.2857 0.6451
P1032 Selectivity increment AVO; Bin7; 2012 * 0.1825 0.2377 −0.2834 0.6484
P1033 Selectivity increment AVO; Bin8; 2012 * 0.1626 0.2112 −0.2513 0.5765
P1034 Selectivity increment AVO; Bin2; 2013 * 0.2090 0.2344 −0.2504 0.6683
P1035 Selectivity increment AVO; Bin3; 2013 * 0.2204 0.2364 −0.2429 0.6837
P1036 Selectivity increment AVO; Bin4; 2013 * 0.2464 0.2350 −0.2142 0.7070
P1037 Selectivity increment AVO; Bin5; 2013 * 0.2349 0.2351 −0.2258 0.6957
P1038 Selectivity increment AVO; Bin6; 2013 * 0.2267 0.2351 −0.2342 0.6875
P1039 Selectivity increment AVO; Bin7; 2013 * 0.2029 0.2354 −0.2585 0.6643
P1040 Selectivity increment AVO; Bin8; 2013 * 0.1606 0.2081 −0.2473 0.5686
P1041 Selectivity increment AVO; Bin2; 2014 * 0.2387 0.2348 −0.2216 0.6989
P1042 Selectivity increment AVO; Bin3; 2014 * 0.2282 0.2328 −0.2281 0.6845
P1043 Selectivity increment AVO; Bin4; 2014 * 0.2623 0.2318 −0.1920 0.7167
P1044 Selectivity increment AVO; Bin5; 2014 * 0.2438 0.2321 −0.2111 0.6986
P1045 Selectivity increment AVO; Bin6; 2014 * 0.2492 0.2316 −0.2048 0.7032
P1046 Selectivity increment AVO; Bin7; 2014 * 0.2315 0.2330 −0.2251 0.6881
P1047 Selectivity increment AVO; Bin8; 2014 * 0.1816 0.2054 −0.2211 0.5842
P1048 Selectivity increment AVO; Bin2; 2015 * 0.1440 0.2281 −0.3030 0.5910
P1049 Selectivity increment AVO; Bin3; 2015 * 0.2648 0.2323 −0.1904 0.7200
P1050 Selectivity increment AVO; Bin4; 2015 * 0.2820 0.2321 −0.1729 0.7370
P1051 Selectivity increment AVO; Bin5; 2015 * 0.2515 0.2330 −0.2053 0.7082
P1052 Selectivity increment AVO; Bin6; 2015 * 0.2218 0.2332 −0.2352 0.6788
P1053 Selectivity increment AVO; Bin7; 2015 * 0.2269 0.2336 −0.2309 0.6847
P1054 Selectivity increment AVO; Bin8; 2015 * 0.2145 0.2058 −0.1888 0.6178
P1055 Selectivity increment AVO; Bin2; 2016 * 0.1171 0.2337 −0.3409 0.5752
P1056 Selectivity increment AVO; Bin3; 2016 * 0.2099 0.2333 −0.2474 0.6671
P1057 Selectivity increment AVO; Bin4; 2016 * 0.2846 0.2324 −0.1708 0.7401
P1058 Selectivity increment AVO; Bin5; 2016 * 0.2301 0.2344 −0.2294 0.6896
P1059 Selectivity increment AVO; Bin6; 2016 * 0.2050 0.2348 −0.2552 0.6652
P1060 Selectivity increment AVO; Bin7; 2016 * 0.2006 0.2352 −0.2604 0.6616
P1061 Selectivity increment AVO; Bin8; 2016 * 0.2355 0.2086 −0.1734 0.6444
P1062 Selectivity increment AVO; Bin2; 2017 * 0.2189 0.2350 −0.2416 0.6795
P1063 Selectivity increment AVO; Bin3; 2017 * 0.1560 0.2388 −0.3121 0.6240
P1064 Selectivity increment AVO; Bin4; 2017 * 0.1020 0.2369 −0.3624 0.5664
P1065 Selectivity increment AVO; Bin5; 2017 * 0.1924 0.2378 −0.2738 0.6585
P1066 Selectivity increment AVO; Bin6; 2017 * 0.2094 0.2389 −0.2588 0.6777
P1067 Selectivity increment AVO; Bin7; 2017 * 0.2076 0.2398 −0.2625 0.6776
P1068 Selectivity increment AVO; Bin8; 2017 * 0.2362 0.2134 −0.1821 0.6545
P1069 Selectivity increment AVO; Bin2; 2018 * 0.1941 0.2406 −0.2776 0.6657
P1070 Selectivity increment AVO; Bin3; 2018 * 0.1519 0.2425 −0.3234 0.6271
P1071 Selectivity increment AVO; Bin4; 2018 * 0.1254 0.2409 −0.3467 0.5975
P1072 Selectivity increment AVO; Bin5; 2018 * 0.1977 0.2397 −0.2722 0.6675
P1073 Selectivity increment AVO; Bin6; 2018 * 0.2034 0.2414 −0.2698 0.6766
P1074 Selectivity increment AVO; Bin7; 2018 * 0.2057 0.2430 −0.2707 0.6820
P1075 Selectivity increment AVO; Bin8; 2018 * 0.2230 0.2169 −0.2022 0.6481
P1076 Selectivity increment AVO; Bin2; 2019 * 0.2102 0.2403 −0.2607 0.6811
P1077 Selectivity increment AVO; Bin3; 2019 * 0.2093 0.2441 −0.2692 0.6878
P1078 Selectivity increment AVO; Bin4; 2019 * 0.2316 0.2446 −0.2477 0.7110
P1079 Selectivity increment AVO; Bin5; 2019 * 0.2064 0.2446 −0.2730 0.6857
P1080 Selectivity increment AVO; Bin6; 2019 * 0.2099 0.2448 −0.2698 0.6897
P1081 Selectivity increment AVO; Bin7; 2019 * 0.2061 0.2448 −0.2737 0.6859
P1082 Selectivity increment AVO; Bin8; 2019 * 0.2140 0.2181 −0.2135 0.6416
P1083 Selectivity increment AVO; Bin2; 2020 * 0.1981 0.2447 −0.2815 0.6777
P1084 Selectivity increment AVO; Bin3; 2020 * 0.2065 0.2472 −0.2781 0.6910
P1085 Selectivity increment AVO; Bin4; 2020 * 0.2306 0.2472 −0.2538 0.7151
P1086 Selectivity increment AVO; Bin5; 2020 * 0.1997 0.2474 −0.2853 0.6847
P1087 Selectivity increment AVO; Bin6; 2020 * 0.1935 0.2475 −0.2916 0.6787
P1088 Selectivity increment AVO; Bin7; 2020 * 0.2048 0.2475 −0.2802 0.6898
P1089 Selectivity increment AVO; Bin8; 2020 * 0.2187 0.2214 −0.2152 0.6527
P1090 Selectivity increment AVO; Bin2; 2021 * 0.1941 0.2490 −0.2939 0.6820
P1091 Selectivity increment AVO; Bin3; 2021 * 0.1939 0.2508 −0.2977 0.6855
P1092 Selectivity increment AVO; Bin4; 2021 * 0.2316 0.2500 −0.2584 0.7216
P1093 Selectivity increment AVO; Bin5; 2021 * 0.1960 0.2505 −0.2951 0.6871
P1094 Selectivity increment AVO; Bin6; 2021 * 0.1941 0.2507 −0.2972 0.6854
P1095 Selectivity increment AVO; Bin7; 2021 * 0.2074 0.2505 −0.2837 0.6985
P1096 Selectivity increment AVO; Bin8; 2021 * 0.2175 0.2256 −0.2246 0.6596
P1097 Selectivity increment AVO; Bin2; 2022 * 0.1766 0.2549 −0.3230 0.6761
P1098 Selectivity increment AVO; Bin3; 2022 * 0.1694 0.2554 −0.3312 0.6701
P1099 Selectivity increment AVO; Bin4; 2022 * 0.2445 0.2534 −0.2521 0.7411
P1100 Selectivity increment AVO; Bin5; 2022 * 0.1840 0.2548 −0.3154 0.6834
P1101 Selectivity increment AVO; Bin6; 2022 * 0.1910 0.2550 −0.3088 0.6908
P1102 Selectivity increment AVO; Bin7; 2022 * 0.2070 0.2551 −0.2930 0.7069
P1103 Selectivity increment AVO; Bin8; 2022 * 0.2136 0.2312 −0.2396 0.6667
P1104 Selectivity increment AVO; Bin2; 2023 * 0.2450 0.2591 −0.2628 0.7527
P1105 Selectivity increment AVO; Bin3; 2023 * 0.2141 0.2631 −0.3016 0.7298
P1106 Selectivity increment AVO; Bin4; 2023 * 0.0901 0.2626 −0.4245 0.6048
P1107 Selectivity increment AVO; Bin5; 2023 * 0.1396 0.2622 −0.3742 0.6535
P1108 Selectivity increment AVO; Bin6; 2023 * 0.1864 0.2622 −0.3274 0.7002
P1109 Selectivity increment AVO; Bin7; 2023 * 0.2082 0.2629 −0.3070 0.7234
P1110 Selectivity increment AVO; Bin8; 2023 * 0.2057 0.2401 −0.2648 0.6762
P1111 Selectivity increment AVO; Bin2; 2024 * 0.2261 0.2708 −0.3046 0.7569
P1112 Selectivity increment AVO; Bin3; 2024 * 0.1919 0.2739 −0.3449 0.7287
P1113 Selectivity increment AVO; Bin4; 2024 * 0.0979 0.2727 −0.4366 0.6324
P1114 Selectivity increment AVO; Bin5; 2024 * 0.1236 0.2711 −0.4077 0.6549
P1115 Selectivity increment AVO; Bin6; 2024 * 0.1798 0.2705 −0.3504 0.7100
P1116 Selectivity increment AVO; Bin7; 2024 * 0.2037 0.2727 −0.3309 0.7382
P1117 Selectivity increment AVO; Bin8; 2024 * 0.1924 0.2513 −0.3001 0.6849
P1118 Selectivity increment AVO; Bin2; 2025 * 0.2192 0.2804 −0.3304 0.7688
P1119 Selectivity increment AVO; Bin3; 2025 * 0.2323 0.2862 −0.3287 0.7934
P1120 Selectivity increment AVO; Bin4; 2025 * 0.1656 0.2871 −0.3970 0.7283
P1121 Selectivity increment AVO; Bin5; 2025 * 0.1703 0.2867 −0.3916 0.7321
P1122 Selectivity increment AVO; Bin6; 2025 * 0.1740 0.2869 −0.3883 0.7362
P1123 Selectivity increment AVO; Bin7; 2025 * 0.1884 0.2866 −0.3734 0.7501
P1124 Selectivity increment AVO; Bin8; 2025 * 0.1812 0.2649 −0.3380 0.7004
P1125 Selectivity increment AVO; Bin2; 2026 * 0.2093 0.3050 −0.3886 0.8072
P1126 Selectivity increment AVO; Bin3; 2026 * 0.2386 0.3046 −0.3585 0.8356
P1127 Selectivity increment AVO; Bin4; 2026 * 0.1551 0.3058 −0.4443 0.7544
P1128 Selectivity increment AVO; Bin5; 2026 * 0.1576 0.3063 −0.4428 0.7581
P1129 Selectivity increment AVO; Bin6; 2026 * 0.1761 0.3067 −0.4251 0.7772
P1130 Selectivity increment AVO; Bin7; 2026 * 0.1927 0.3064 −0.4078 0.7932
P1131 Selectivity increment AVO; Bin8; 2026 * 0.1815 0.2852 −0.3775 0.7406
P1132 Log logistic slope Asc; BTS −0.8376 0.1962 −1.2221 −0.4531
P1133 Logistic midpoint Asc; BTS 6.9805 0.6409 5.7244 8.2367
P1134 BTS age-1 log selectivity Age-1 component; BTS −3.0479 0.3067 −3.6490 −2.4469
P1135 BTS slope deviation Asc; BTS; 1983 0.9087 0.2274 0.4630 1.3543
P1136 BTS slope deviation Asc; BTS; 1984 0.7382 0.2286 0.2901 1.1863
P1137 BTS slope deviation Asc; BTS; 1985 0.2475 0.2461 −0.2348 0.7297
P1138 BTS slope deviation Asc; BTS; 1986 0.3667 0.2364 −0.0965 0.8300
P1139 BTS slope deviation Asc; BTS; 1987 0.3474 0.2949 −0.2306 0.9254
P1140 BTS slope deviation Asc; BTS; 1988 0.3002 0.3348 −0.3559 0.9564
P1141 BTS slope deviation Asc; BTS; 1989 0.5436 0.3985 −0.2374 1.3245
P1142 BTS slope deviation Asc; BTS; 1990 1.2073 0.3076 0.6043 1.8102
P1143 BTS slope deviation Asc; BTS; 1991 1.0413 0.2581 0.5355 1.5471
P1144 BTS slope deviation Asc; BTS; 1992 0.9879 0.2549 0.4883 1.4875
P1145 BTS slope deviation Asc; BTS; 1993 1.1449 0.2594 0.6365 1.6532
P1146 BTS slope deviation Asc; BTS; 1994 1.1404 0.2336 0.6827 1.5982
P1147 BTS slope deviation Asc; BTS; 1995 1.0736 0.2332 0.6165 1.5307
P1148 BTS slope deviation Asc; BTS; 1996 0.6664 0.2162 0.2428 1.0901
P1149 BTS slope deviation Asc; BTS; 1997 0.5019 0.2354 0.0406 0.9632
P1150 BTS slope deviation Asc; BTS; 1998 0.2949 0.2285 −0.1530 0.7427
P1151 BTS slope deviation Asc; BTS; 1999 0.2464 0.2318 −0.2079 0.7008
P1152 BTS slope deviation Asc; BTS; 2000 0.5104 0.2470 0.0264 0.9944
P1153 BTS slope deviation Asc; BTS; 2001 0.3417 0.2233 −0.0959 0.7793
P1154 BTS slope deviation Asc; BTS; 2002 0.7946 0.2240 0.3556 1.2337
P1155 BTS slope deviation Asc; BTS; 2003 1.0199 0.2354 0.5585 1.4812
P1156 BTS slope deviation Asc; BTS; 2004 0.9485 0.2234 0.5106 1.3864
P1157 BTS slope deviation Asc; BTS; 2005 1.0394 0.2342 0.5803 1.4985
P1158 BTS slope deviation Asc; BTS; 2006 0.7304 0.2221 0.2950 1.1657
P1159 BTS slope deviation Asc; BTS; 2007 1.1604 0.2459 0.6785 1.6424
P1160 BTS slope deviation Asc; BTS; 2008 1.3498 0.2211 0.9164 1.7832
P1161 BTS slope deviation Asc; BTS; 2009 1.0541 0.2284 0.6065 1.5016
P1162 BTS slope deviation Asc; BTS; 2010 1.5895 0.2493 1.1008 2.0781
P1163 BTS slope deviation Asc; BTS; 2011 1.3653 0.2144 0.9450 1.7856
P1164 BTS slope deviation Asc; BTS; 2012 1.0054 0.2373 0.5403 1.4705
P1165 BTS slope deviation Asc; BTS; 2013 1.1035 0.2417 0.6297 1.5773
P1166 BTS slope deviation Asc; BTS; 2014 1.3500 0.2227 0.9136 1.7864
P1167 BTS slope deviation Asc; BTS; 2015 1.2379 0.2284 0.7902 1.6856
P1168 BTS slope deviation Asc; BTS; 2016 1.2450 0.2421 0.7705 1.7195
P1169 BTS slope deviation Asc; BTS; 2017 1.0643 0.2207 0.6317 1.4968
P1170 BTS slope deviation Asc; BTS; 2018 0.5311 0.2347 0.0711 0.9911
P1171 BTS slope deviation Asc; BTS; 2019 0.8316 0.2327 0.3755 1.2876
P1172 BTS slope deviation Asc; BTS; 2020 0.7195 0.2985 0.1345 1.3046
P1173 BTS slope deviation Asc; BTS; 2021 0.6483 0.2169 0.2232 1.0734
P1174 BTS slope deviation Asc; BTS; 2022 0.8388 0.2317 0.3848 1.2929
P1175 BTS slope deviation Asc; BTS; 2023 0.5333 0.2269 0.0887 0.9779
P1176 BTS slope deviation Asc; BTS; 2024 0.5612 0.2527 0.0660 1.0564
P1177 BTS slope deviation Asc; BTS; 2025 0.6074 0.2290 0.1586 1.0562
P1178 BTS slope deviation Asc; BTS; 2026 0.8008 0.2609 0.2895 1.3121
P1179 BTS midpoint deviation Asc; BTS; 1983 −0.3111 0.0866 −0.4808 −0.1414
P1180 BTS midpoint deviation Asc; BTS; 1984 −0.1267 0.0895 −0.3021 0.0488
P1181 BTS midpoint deviation Asc; BTS; 1985 0.0383 0.0942 −0.1463 0.2229
P1182 BTS midpoint deviation Asc; BTS; 1986 0.0274 0.0975 −0.1637 0.2186
P1183 BTS midpoint deviation Asc; BTS; 1987 −0.0750 0.1102 −0.2909 0.1409
P1184 BTS midpoint deviation Asc; BTS; 1988 −0.2158 0.1232 −0.4573 0.0258
P1185 BTS midpoint deviation Asc; BTS; 1989 −0.2963 0.1204 −0.5324 −0.0603
P1186 BTS midpoint deviation Asc; BTS; 1990 −0.3506 0.1113 −0.5688 −0.1323
P1187 BTS midpoint deviation Asc; BTS; 1991 −0.2509 0.1111 −0.4688 −0.0331
P1188 BTS midpoint deviation Asc; BTS; 1992 −0.2448 0.1085 −0.4575 −0.0322
P1189 BTS midpoint deviation Asc; BTS; 1993 −0.2921 0.1020 −0.4920 −0.0922
P1190 BTS midpoint deviation Asc; BTS; 1994 −0.2291 0.0979 −0.4210 −0.0373
P1191 BTS midpoint deviation Asc; BTS; 1995 −0.1343 0.1012 −0.3326 0.0640
P1192 BTS midpoint deviation Asc; BTS; 1996 0.0653 0.0961 −0.1230 0.2536
P1193 BTS midpoint deviation Asc; BTS; 1997 0.1110 0.1035 −0.0917 0.3138
P1194 BTS midpoint deviation Asc; BTS; 1998 0.1916 0.1005 −0.0054 0.3885
P1195 BTS midpoint deviation Asc; BTS; 1999 0.1329 0.1076 −0.0780 0.3439
P1196 BTS midpoint deviation Asc; BTS; 2000 −0.0032 0.1111 −0.2210 0.2145
P1197 BTS midpoint deviation Asc; BTS; 2001 0.0394 0.1009 −0.1583 0.2372
P1198 BTS midpoint deviation Asc; BTS; 2002 −0.0939 0.1011 −0.2920 0.1042
P1199 BTS midpoint deviation Asc; BTS; 2003 −0.1374 0.1034 −0.3402 0.0653
P1200 BTS midpoint deviation Asc; BTS; 2004 −0.1130 0.0971 −0.3033 0.0773
P1201 BTS midpoint deviation Asc; BTS; 2005 −0.1589 0.0977 −0.3504 0.0326
P1202 BTS midpoint deviation Asc; BTS; 2006 −0.0355 0.0960 −0.2237 0.1527
P1203 BTS midpoint deviation Asc; BTS; 2007 −0.2089 0.0993 −0.4035 −0.0143
P1204 BTS midpoint deviation Asc; BTS; 2008 −0.2335 0.0961 −0.4219 −0.0451
P1205 BTS midpoint deviation Asc; BTS; 2009 −0.1517 0.0988 −0.3454 0.0420
P1206 BTS midpoint deviation Asc; BTS; 2010 −0.3339 0.0978 −0.5256 −0.1421
P1207 BTS midpoint deviation Asc; BTS; 2011 −0.2094 0.0940 −0.3936 −0.0251
P1208 BTS midpoint deviation Asc; BTS; 2012 −0.1593 0.0986 −0.3526 0.0339
P1209 BTS midpoint deviation Asc; BTS; 2013 −0.1905 0.0946 −0.3760 −0.0050
P1210 BTS midpoint deviation Asc; BTS; 2014 −0.2790 0.0959 −0.4670 −0.0911
P1211 BTS midpoint deviation Asc; BTS; 2015 −0.3231 0.0976 −0.5144 −0.1318
P1212 BTS midpoint deviation Asc; BTS; 2016 −0.2689 0.0984 −0.4617 −0.0762
P1213 BTS midpoint deviation Asc; BTS; 2017 −0.1865 0.0941 −0.3709 −0.0020
P1214 BTS midpoint deviation Asc; BTS; 2018 −0.0140 0.0995 −0.2090 0.1811
P1215 BTS midpoint deviation Asc; BTS; 2019 −0.1490 0.0969 −0.3390 0.0410
P1216 BTS midpoint deviation Asc; BTS; 2020 −0.0624 0.1177 −0.2930 0.1683
P1217 BTS midpoint deviation Asc; BTS; 2021 0.0125 0.0977 −0.1790 0.2041
P1218 BTS midpoint deviation Asc; BTS; 2022 −0.0671 0.0992 −0.2617 0.1274
P1219 BTS midpoint deviation Asc; BTS; 2023 0.0978 0.0985 −0.0952 0.2909
P1220 BTS midpoint deviation Asc; BTS; 2024 0.0068 0.1052 −0.1993 0.2130
P1221 BTS midpoint deviation Asc; BTS; 2025 0.0317 0.1021 −0.1684 0.2319
P1222 BTS midpoint deviation Asc; BTS; 2026 −0.1099 0.1145 −0.3344 0.1146
P1223 BTS age-1 deviation Age-1 component; BTS; 1983 −0.0145 0.1177 −0.2452 0.2162
P1224 BTS age-1 deviation Age-1 component; BTS; 1984 0.0371 0.1648 −0.2858 0.3600
P1225 BTS age-1 deviation Age-1 component; BTS; 1985 −0.1923 0.1416 −0.4698 0.0851
P1226 BTS age-1 deviation Age-1 component; BTS; 1986 −0.4013 0.1448 −0.6851 −0.1174
P1227 BTS age-1 deviation Age-1 component; BTS; 1987 −0.2452 0.1911 −0.6198 0.1294
P1228 BTS age-1 deviation Age-1 component; BTS; 1988 −0.2987 0.1852 −0.6616 0.0643
P1229 BTS age-1 deviation Age-1 component; BTS; 1989 −0.0598 0.1804 −0.4134 0.2939
P1230 BTS age-1 deviation Age-1 component; BTS; 1990 0.1030 0.1485 −0.1881 0.3941
P1231 BTS age-1 deviation Age-1 component; BTS; 1991 −0.1431 0.1368 −0.4113 0.1250
P1232 BTS age-1 deviation Age-1 component; BTS; 1992 −0.0165 0.1370 −0.2849 0.2520
P1233 BTS age-1 deviation Age-1 component; BTS; 1993 0.0411 0.1297 −0.2131 0.2953
P1234 BTS age-1 deviation Age-1 component; BTS; 1994 −0.1102 0.1451 −0.3946 0.1741
P1235 BTS age-1 deviation Age-1 component; BTS; 1995 −0.1370 0.1474 −0.4259 0.1519
P1236 BTS age-1 deviation Age-1 component; BTS; 1996 −0.1046 0.1174 −0.3346 0.1254
P1237 BTS age-1 deviation Age-1 component; BTS; 1997 0.0048 0.1318 −0.2534 0.2631
P1238 BTS age-1 deviation Age-1 component; BTS; 1998 0.0560 0.1447 −0.2275 0.3395
P1239 BTS age-1 deviation Age-1 component; BTS; 1999 0.0971 0.1390 −0.1753 0.3695
P1240 BTS age-1 deviation Age-1 component; BTS; 2000 0.1927 0.1380 −0.0778 0.4631
P1241 BTS age-1 deviation Age-1 component; BTS; 2001 0.0776 0.1172 −0.1521 0.3073
P1242 BTS age-1 deviation Age-1 component; BTS; 2002 0.0837 0.1210 −0.1534 0.3209
P1243 BTS age-1 deviation Age-1 component; BTS; 2003 0.2335 0.1390 −0.0389 0.5059
P1244 BTS age-1 deviation Age-1 component; BTS; 2004 0.0473 0.1386 −0.2242 0.3189
P1245 BTS age-1 deviation Age-1 component; BTS; 2005 −0.0147 0.1483 −0.3054 0.2759
P1246 BTS age-1 deviation Age-1 component; BTS; 2006 −0.0132 0.1166 −0.2417 0.2153
P1247 BTS age-1 deviation Age-1 component; BTS; 2007 −0.0358 0.1179 −0.2668 0.1952
P1248 BTS age-1 deviation Age-1 component; BTS; 2008 0.2024 0.1181 −0.0291 0.4340
P1249 BTS age-1 deviation Age-1 component; BTS; 2009 0.3586 0.1115 0.1400 0.5773
P1250 BTS age-1 deviation Age-1 component; BTS; 2010 0.3397 0.1320 0.0809 0.5984
P1251 BTS age-1 deviation Age-1 component; BTS; 2011 −0.0718 0.1226 −0.3121 0.1685
P1252 BTS age-1 deviation Age-1 component; BTS; 2012 −0.0599 0.1366 −0.3276 0.2078
P1253 BTS age-1 deviation Age-1 component; BTS; 2013 0.2090 0.1341 −0.0539 0.4719
P1254 BTS age-1 deviation Age-1 component; BTS; 2014 0.1700 0.1236 −0.0723 0.4123
P1255 BTS age-1 deviation Age-1 component; BTS; 2015 0.0604 0.1400 −0.2139 0.3347
P1256 BTS age-1 deviation Age-1 component; BTS; 2016 −0.0342 0.1521 −0.3322 0.2639
P1257 BTS age-1 deviation Age-1 component; BTS; 2017 −0.0710 0.1368 −0.3392 0.1972
P1258 BTS age-1 deviation Age-1 component; BTS; 2018 −0.0545 0.1279 −0.3053 0.1962
P1259 BTS age-1 deviation Age-1 component; BTS; 2019 0.2778 0.1171 0.0483 0.5074
P1260 BTS age-1 deviation Age-1 component; BTS; 2020 0.1488 0.2105 −0.2638 0.5614
P1261 BTS age-1 deviation Age-1 component; BTS; 2021 0.0198 0.1341 −0.2431 0.2826
P1262 BTS age-1 deviation Age-1 component; BTS; 2022 0.0699 0.1373 −0.1992 0.3390
P1263 BTS age-1 deviation Age-1 component; BTS; 2023 −0.0696 0.1428 −0.3494 0.2102
P1264 BTS age-1 deviation Age-1 component; BTS; 2024 0.1744 0.1502 −0.1201 0.4689
P1265 BTS age-1 deviation Age-1 component; BTS; 2025 0.0580 0.1478 −0.2317 0.3477
P1266 BTS age-1 deviation Age-1 component; BTS; 2026 −0.0438 0.2085 −0.4524 0.3649
* A parameter is shared across additional positions. The full shared-position mappings are in the numerical parameter table.
The BTS age-1 component reuses native coordinates named Descending; it is a separate first-age component rather than a descending limb. Its baseline is log selectivity, and its annual deviations multiply that baseline log value. Midpoint deviations likewise multiply the baseline midpoint. The selectivity table combines these parameters and their uncertainty.

Note. All estimated parameters and approximate 95% confidence intervals in Model 26.0, on their estimation scales. The parameter ID links to the complete numerical data and shared-parameter mappings. Recruitment and selectivity deviations are expressed on their fitted deviation or increment scales; the biological and selectivity schedules show their realized effects. The full precision data also supply natural-scale transformations where applicable.

Table D2 Largest Pairwise Correlations Among Model 26.0 Parameters
Strong parameter correlations
Parameter 1 Parameter 2 Correlation
P0001: Recruitment level: EBS Pollock; R0 P0039: Recruitment deviation: EBS Pollock; 2001 −0.96375
P0001: Recruitment level: EBS Pollock; R0 P0051: Recruitment deviation: EBS Pollock; 2013 −0.96370
P0001: Recruitment level: EBS Pollock; R0 P0047: Recruitment deviation: EBS Pollock; 2009 −0.96198
P0001: Recruitment level: EBS Pollock; R0 P0052: Recruitment deviation: EBS Pollock; 2014 −0.96036
P0001: Recruitment level: EBS Pollock; R0 P0028: Recruitment deviation: EBS Pollock; 1990 −0.95676
P1133: Logistic midpoint: Ascending; BTS; Sex combined P1207: BTS midpoint deviation: Ascending; BTS; Sex combined; 2011 −0.95670
P1133: Logistic midpoint: Ascending; BTS; Sex combined P1213: BTS midpoint deviation: Ascending; BTS; Sex combined; 2017 −0.95529
P0001: Recruitment level: EBS Pollock; R0 P0040: Recruitment deviation: EBS Pollock; 2002 −0.95229
P0001: Recruitment level: EBS Pollock; R0 P0035: Recruitment deviation: EBS Pollock; 1997 −0.95002
P0001: Recruitment level: EBS Pollock; R0 P0045: Recruitment deviation: EBS Pollock; 2007 −0.94802

Note. Ten largest absolute pairwise correlations among Model 26.0 estimated parameters. IDs link to the complete parameter table; correlations close to plus or minus one identify parameter combinations that change together. These are parameter correlations rather than correlations between survey observations.

Appendix E
Proposed Projection Input Curves

The proposed three-year fishery-selectivity average is compared with the window including the inferred 2026 curve (Figure E1). The technical appendix records their conditional projection effects.

Fishery selectivity at ages 1 to 15 plus compares the proposed 2023 to 2025 average with a 2024 to 2026 average. Solid-circle and dashed-triangle curves distinguish the two selected averaging windows. Colour, line type and point shape distinguish the curves.

Note. Proposed three-year fishery selectivity and the alternative window check. The two curves are distinguished by colour, line type and point shape.

Figure E1 Proposed Fishery Selectivity and Alternative Averaging Window

The projection uses the fixed 2027 fishery forecast for both catch and spawning weights, alongside the population-weight schedule (Figure E2).

Four curves show weight in kilograms by age. The projected fishery schedule differs from 2026 weights, particularly at younger selected ages. Population and spawning weights are held at 2026 levels. Colour, line type and point shape distinguish schedules.

Note. Projection weight schedules: the fixed 2027 fishery forecast supplies catch and spawning weights at ages 3–15+; population weights retain the schedule.

Figure E2 Weight Schedules for the Proposed Projection

Appendix F
Model Equations

Scope. This appendix carries forward the structure and model components of the 2024 Appendix EBS Pollock Model Description (SAFE pp. 172–182). The equations describe the Model 23.0 ADMB comparison. The proposed Model 26.0 configuration and its weight schedules are described in Section 5 and Section 4.1.3. The historical Tier 1 material documents an available calculation; the December 2024 SSC adopted Tier 3a.

Dynamics

The statistical age-structured model combines the catch equation with annual survival and an accumulating terminal age group (Fournier and Archibald 1982; Hilborn and Walters 1992; Schnute and Richards 1995; McAllister and Ianelli 1997). Let tt index years, a=1,…,Aa=1,\ldots,A index ages, and A=15A=15 denote ages 15 and older. Nt,aN_{t,a} is abundance at the start of the year, Ft,aF_{t,a} and Mt,aM_{t,a} are annual instantaneous mortality rates, and Zt,aZ_{t,a} is their sum. Catch at age and catch biomass are

Zt,a=Ft,a+Mt,a,Ct,a=Nt,aFt,aZt,a(1−e−Zt,a),Yt=∑a=1ACt,awt,af,pt,af=Ct,a∑bCt,b.(2) \begin{aligned} Z_{t,a}&=F_{t,a}+M_{t,a},\\ C_{t,a}&=N_{t,a}\frac{F_{t,a}}{Z_{t,a}}(1-e^{-Z_{t,a}}),\\ Y_t&=\sum_{a=1}^{A}C_{t,a}w^{f}_{t,a},\qquad p^f_{t,a}=\frac{C_{t,a}}{\sum_b C_{t,b}}. \end{aligned} \qquad(2)

Here wt,afw^f_{t,a} is fishery weight-at-age. Abundance in millions of fish multiplied by kg per fish gives biomass in kt. The population advances as

Nt+1,1=Rt+1,Nt+1,a+1=Nt,ae−Zt,a,1≤a<A,Nt+1,A=Nt,A−1e−Zt,A−1+Nt,Ae−Zt,A.(3) \begin{aligned} N_{t+1,1}&=R_{t+1},\\ N_{t+1,a+1}&=N_{t,a}e^{-Z_{t,a}}, &&1\leq a<A,\\ N_{t+1,A}&=N_{t,A-1}e^{-Z_{t,A-1}}+N_{t,A}e^{-Z_{t,A}}. \end{aligned} \qquad(3)

The middle line applies to entry from each younger age; the final line adds surviving members of the plus group. This corrects the age subscript in 2024 Eq. 14.2, which printed a−1a-1 on the right side while advancing aa to a+1a+1 on the left.

Fishing mortality separates annual intensity from selectivity at age:

Ft,a=st,afμFeϵt.(4) F_{t,a}=s^f_{t,a}\mu_F e^{\epsilon_t}. \qquad(4)

The assessment estimates selectivity coefficients with penalties on changes over time and on curvature across ages (Butterworth et al. 2003). In a general penalty notation, Δtlog⁡st,a\Delta_t\log s_{t,a} controls annual changes and Δa2log⁡st,a\Delta_a^2\log s_{t,a} controls smoothness across ages. Their weights and allowed change years come from the run controls.

The bottom-trawl survey (BTS) uses logistic selectivity above age one and a separate age-one term. The implemented form is

st,ab={1+exp⁡[−kt(a−a50,t)]}−1,a>1,log⁡st,1b=b1exp⁡(dt),kt=k‾exp⁡(ut),a50,t=a‾50exp⁡(vt).(5) \begin{aligned} s^{b}_{t,a}&=\{1+\exp[-k_t(a-a_{50,t})]\}^{-1}, &&a>1,\\ \log s^{b}_{t,1}&=b_1\exp(d_t),\\ k_t&=\bar k\exp(u_t),\qquad a_{50,t}=\bar a_{50}\exp(v_t). \end{aligned} \qquad(5)

This follows compute_selectivity() and the age-one assignment in Get_Selectivity(). It replaces the ambiguous slope/intercept and age-one expressions printed in 2024. The 2024 description reported a process variance of 0.04 for an earlier random-walk formulation. The retained controls instead select the penalty on changes in log-selectivity at the specified ages, plus the separate age-one deviation penalty. Its coefficient is 8 for the squared first differences of dtd_t. The actual controls and source identify which parameter or log-selectivity penalty is applied.

Acoustic-trawl survey (ATS) selectivity is flexible across ages; the optional separate age-one index leaves ages 2–15+ in its composition likelihood. Constant survey catchability and time-varying selectivity represent separate model components.

Recruitment

Recruitment is abundance at age one. Female spawning biomass accounts for survival from the start of the year to spawning:

Bt=∑a=1ANt,aexp⁡(−τZt,a)ϕawt,as,τ=0.25.(6) B_t=\sum_{a=1}^{A}N_{t,a}\exp(-\tau Z_{t,a})\phi_a w^s_{t,a}, \qquad \tau=0.25. \qquad(6)

Here wt,asw^s_{t,a} is spawning weight and ϕa\phi_a includes both maturity and the female fraction. The assessment reads a maturity schedule and applies the female fraction internally; the one-sex SPM handoff reads maturity and halves total abundance. Applying the female fraction once preserves the same biomass definition. The spawning time is April 1 (month 4).

Annual recruitment deviations accompany a stock–recruit function, Rt=f(Bt−1)exp⁡(εt)R_t=f(B_{t-1})\exp(\varepsilon_t), with log-scale deviation penalties and the implementation’s bias adjustment. The Ricker option selected by SrType=1 is

f(B)=Bψ0exp⁡[αR(1−BB0)],B0=R0ψ0,αR=log⁡(4hADMB1−hADMB).(7) f(B)=\frac{B}{\psi_0}\exp\!\left[\alpha_R\left(1-\frac{B}{B_0}\right)\right], \qquad B_0=R_0\psi_0,\qquad \alpha_R=\log\!\left(\frac{4h_{\mathrm{ADMB}}}{1-h_{\mathrm{ADMB}}}\right). \qquad(7)

ψ0\psi_0 is unfished spawning biomass per recruit. The final expression is the source code’s transformation of its parameter named steepness; it is retained as hADMBh_{\mathrm{ADMB}} to identify that convention. The 2024 printed Ricker equation misplaced R0R_0 in the biomass ratio. The expression here follows SRecruit() and Get_Bzero() in the preserved template.

The alternative Beverton–Holt relationship (Francis 1992) is

fBH(B)=BαBH+βBHB,αBH=ψ01−h4h,βBH=5h−14hR0.(8) f_{\mathrm{BH}}(B)=\frac{B}{\alpha_{\mathrm{BH}}+\beta_{\mathrm{BH}}B},\qquad \alpha_{\mathrm{BH}}=\psi_0\frac{1-h}{4h},\qquad \beta_{\mathrm{BH}}=\frac{5h-1}{4hR_0}. \qquad(8)

For this alternative, hh is the fraction of unfished recruitment at 20% of unfished spawning biomass. The 2024 controls fix σR=1\sigma_R=1 and specify a symmetric beta prior with shape parameters 14.93209877 for the selected stock–recruit parameter. The earlier Beverton–Holt example in the 2024 appendix used a different prior; it remains an alternative rather than the selected 2024 setting.

Diagnostics

The historical replay diagnostic retains fitted recruitment anomalies while adjusting recruitment for the change in spawning biomass under a hypothetical history with fishing set to zero:

Rt′=R̂tf(Bt−1′)f(Bt−1).(9) R'_t=\widehat R_t\frac{f(B'_{t-1})}{f(B_{t-1})}. \qquad(9)

Retrospective analyses repeat estimation after removing recent years and compare estimates for common years (Parma 1993; Ianelli and Fournier 1998). Their fit controls and terminal years accompany each saved run.

The effective number of ages contributing to spawning biomass is the exponential of Shannon entropy (Jost 2006):

Dt=exp⁡(−∑apt,aBlogpt,aB),pt,aB=Nt,ae−τZt,aϕawt,asBt.(10) D_t=\exp\!\left(-\sum_a p^{B}_{t,a}\log p^{B}_{t,a}\right),\qquad p^{B}_{t,a}=\frac{N_{t,a}e^{-\tau Z_{t,a}}\phi_a w^s_{t,a}}{B_t}. \qquad(10)

The mean-age diagnostic uses observed and predicted composition means and the predicted variance at age (Francis 2011):

a‾t=∑aapt,a,a‾̂t=∑aap̂t,a,Vt=∑a(a−a‾̂t)2p̂t,a,zt=a‾t−a‾̂tVt/nt,ν={Var⁡t(zt)}−1.(11) \begin{aligned} \bar a_t&=\sum_a a p_{t,a},\qquad \widehat{\bar a}_t=\sum_a a\widehat p_{t,a},\\ V_t&=\sum_a(a-\widehat{\bar a}_t)^2\widehat p_{t,a},\\ z_t&=\frac{\bar a_t-\widehat{\bar a}_t}{\sqrt{V_t/n_t}},\qquad \nu=\{\operatorname{Var}_t(z_t)\}^{-1}. \end{aligned} \qquad(11)

The implied adjusted sample size is νnt\nu n_t. This diagnostic supports evaluation of weighting; changing assessment inputs requires a decision. The expression for VtV_t replaces the malformed κt\kappa_t formula in the printed 2024 appendix.

Parameter estimation

The objective adds negative log likelihoods, prior densities and selectivity penalties. Phase-based estimation introduces parameters in stages. For age compositions, the multinomial contribution, up to a data-only constant, is

ℓage=−∑tnt∑apt,alog⁡(p̂t,a+c),𝒑̂tread=𝒑̂ttrueE.(12) \ell_{\mathrm{age}}=-\sum_t n_t\sum_a p_{t,a}\log(\widehat p_{t,a}+c), \qquad \widehat{\boldsymbol p}^{\,\mathrm{read}}_t =\widehat{\boldsymbol p}^{\,\mathrm{true}}_t E. \qquad(12)

cc is the small numerical constant in the implementation. When enabled, Ea,bE_{a,b} is the probability that true age aa is read as age bb. The selected historical controls have use_age_err=0. The original appendix also described a robust composition option (Fournier et al. 1990), with variance inflation and a small outlier component. In the retained 2024 controls its activation phase is 1350; the six-phase completed comparison uses the multinomial form. This distinction prevents the general software description from implying that the robust option was active.

For survey ss at within-year time τs\tau_s, expected abundance and biomass at age are

N̂t,as=qsst,asNt,ae−τsZt,a,Îts=∑aN̂t,aswt,as.(13) \widehat N^s_{t,a}=q_s s^s_{t,a}N_{t,a}e^{-\tau_s Z_{t,a}},\qquad \widehat I^s_t=\sum_a\widehat N^s_{t,a}w^s_{t,a}. \qquad(13)

An abundance index omits the weight multiplier. The original description used midyear survey timing; actual run inputs specify the timing used in each comparison. The AVO index shares ATS selectivity and its documented weight basis, while retaining a separate catchability coefficient.

The independent lognormal-index and multivariate BTS contributions have the forms

ℓs=12∑t[log⁡Is,tobs−log⁡Îs,t]2σs,t2,ℓBTS=12𝒓𝖳Σ−1𝒓,rt=log⁡Itobs−log⁡Ît.(14) \ell_s=\frac12\sum_t\frac{[\log I^{\mathrm{obs}}_{s,t}-\log\widehat I_{s,t}]^2} {\sigma^2_{s,t}},\qquad \ell_{\mathrm{BTS}}=\frac12\boldsymbol r^{\mathsf{T}}\Sigma^{-1}\boldsymbol r, \quad r_t=\log I^{\mathrm{obs}}_t-\log\widehat I_t. \qquad(14)

Fixed-variance normalization terms are constant for these comparisons. The normal-index option described in 2024 instead uses residuals on the original scale. The BTS covariance provides Σ\Sigma for the multivariate lognormal fit. Catch biomass enters the implemented objective as λC∑t[log⁡(Ytobs+c)−log⁡(Ŷt+c)]2\lambda_C\sum_t[\log(Y_t^{\mathrm{obs}}+c)-\log(\widehat Y_t+c)]^2, with λC=200\lambda_C=200 in the retained controls. This equals 1/(2σC2)1/(2\sigma_C^2) for σC=0.05\sigma_C=0.05 and removes the extra factor of two in the printed 2024 likelihood expression. Priors and penalties retain their actual source-code weights.

Uncertainty in mean body mass

The 2024 appendix described estimating future weights within the assessment to propagate uncertainty into derived quantities (Ianelli and Williamson 2001). Its earlier option used wafuture∼𝒩(w‾a,σw,a2)w^{\mathrm{future}}_a\sim\mathcal{N}(\bar w_a,\sigma_{w,a}^2). The retained implementation fits a mean growth curve plus cohort and year effects. For starting modeled age a0a_0, its mean curve is

w‾a=αw{L1+(L2−L1)1−Ka−a01−KA−1}3.(15) \bar w_a=\alpha_w\left\{L_1+(L_2-L_1) \frac{1-K^{a-a_0}}{1-K^{A-1}}\right\}^{3}. \qquad(15)

At the final estimation phase, the recurrence in Est_Fixed_Effects_wts() is

ŵt,a0=w‾a0exp⁡(σc2/2+σcct),ŵt,a=ŵt−1,a−1+(w‾a−w‾a−1)exp⁡(σy2/2+σyyt),a>a0.(16) \begin{aligned} \widehat w_{t,a_0}&=\bar w_{a_0} \exp(\sigma_c^2/2+\sigma_c c_t),\\ \widehat w_{t,a}&=\widehat w_{t-1,a-1} +(\bar w_a-\bar w_{a-1})\exp(\sigma_y^2/2+\sigma_y y_t), &&a>a_0. \end{aligned} \qquad(16)

The initial year starts at w‾a\bar w_a; dataset-specific scale vectors map the latent weights to observation series. This notation corrects the increment index in 2024 and explicitly retains the implementation’s sigma scaling and final-phase offsets. The cohort and year deviations receive standard-normal penalties. The four-term weight objective is

ℓw=12∑h,t,a(wh,t,aobs−w‾a)2σh,t,a2+12∑h,t,a(wh,t,aobs−ŵh,t,a)2σh,t,a2+12∑tct2+12∑tyt2.(17) \ell_w=\frac12\sum_{h,t,a} \frac{(w^{\mathrm{obs}}_{h,t,a}-\bar w_a)^2}{\sigma^2_{h,t,a}} +\frac12\sum_{h,t,a} \frac{(w^{\mathrm{obs}}_{h,t,a}-\widehat w_{h,t,a})^2}{\sigma^2_{h,t,a}} +\frac12\sum_t c_t^2+\frac12\sum_t y_t^2. \qquad(17)

The 2026 numerical baseline allocates all four terms and retains their sum.

Tier 1 projections: historical calculation

The 2024 description retained a Tier 1 calculation based on fishable biomass, the harmonic-mean harvest rate at MSY, and a spawning-biomass adjustment:

ABCt=BGM,tfûHMζt,BGM,tf=exp⁡{log⁡B̂tf−σlog⁡Bf2/2},ûHM=exp⁡{log⁡ûMSY−σlog⁡u2/2},ζt={(Bt/BMSY−0.05)/0.95,Bt<BMSY,1,Bt≥BMSY.(18) \begin{aligned} ABC_t&=B^f_{{\mathrm{GM}},t}\widehat u_{\mathrm{HM}}\zeta_t,\\ B^f_{{\mathrm{GM}},t}&=\exp\{\log\widehat B^f_t-\sigma^2_{\log B^f}/2\},\\ \widehat u_{\mathrm{HM}}&=\exp\{\log\widehat u_{\mathrm{MSY}}-\sigma^2_{\log u}/2\},\\ \zeta_t&=\begin{cases} (B_t/B_{\mathrm{MSY}}-0.05)/0.95,&B_t<B_{\mathrm{MSY}},\\ 1,&B_t\geq B_{\mathrm{MSY}}. \end{cases} \end{aligned} \qquad(18)

The geometric and harmonic adjustments assume the documented lognormal approximations. This historical formula describes the earlier calculation over its applicable biomass range; final advice uses the adopted tier and the complete corresponding harvest-control rule.

Tier 3 projections

For fixed mortality, maturity, weights and selectivity, equilibrium spawning biomass per recruit at fishing intensity FF is

l1(F)=1,la(F)=la−1(F)e−Ma−1−Fsa−1,1<a<A,lA(F)=lA−1(F)e−MA−1−FsA−11−e−MA−FsA,ψ(F)=∑ala(F)ϕawase−τ(Ma+Fsa),B100%=R‾ψ(0),Bx%=x100B100%,ψ(Fx%)ψ(0)=x100.(19) \begin{aligned} l_1(F)&=1,\qquad l_a(F)=l_{a-1}(F)e^{-M_{a-1}-Fs_{a-1}}, &&1<a<A,\\ l_A(F)&=\frac{l_{A-1}(F)e^{-M_{A-1}-Fs_{A-1}}}{1-e^{-M_A-Fs_A}},\\ \psi(F)&=\sum_a l_a(F)\phi_a w^s_a e^{-\tau(M_a+Fs_a)},\\ B_{100\%}&=\bar R\psi(0),\qquad B_{x\%}=\frac{x}{100}B_{100\%},\qquad \frac{\psi(F_{x\%})}{\psi(0)}=\frac{x}{100}. \end{aligned} \qquad(19)

Tier 3a uses F40%F_{40\%} for maximum ABC and F35%F_{35\%} for OFL, with the adopted biomass-dependent rule applied when needed. Projection catch follows Equation 2. The 2024 SPM calculation used one sex category split equally into females and males, fixed biological schedules and selectivity, and stochastic recruitment generated from the historical arithmetic and harmonic means with an inverse-Gaussian distribution. Its 1,000 simulations retained recruitment process variability; uncertainty in fitted abundance, mean recruitment, selectivity and weights was omitted. The saved seed is 123 in the historical SPM source.

The recovered 2024 handoff uses five preceding selectivity years (2019–2023), April spawning, the terminal spawning weights and fitted future fishery weights. SPM averages age-one recruitment over 1978–2023; the assessment’s B100%B_{100\%} calculation includes 2024. These different recruitment means produce different reference-point values. The selected scenario fixes catches at 1,350 kt in both 2025 and 2026. Its archived simulation means provide the historical forecast comparison.

Appendix G
FT-NIRS Age Prediction for EBS Pollock

Authored by: Derek Chamberlin, Esther Goldstein, Beth Matta, and Jason Conner

FT-NIRS Team: John Brogan, Jason Conner, Derek Chamberlin, Esther Goldstein, Brenna Hsieh, Beth Matta, Jon Short

FT-NIRS predicts age from otolith spectra and associated specimen information, using traditional microscopic ages for calibration and validation. The workflow proceeds from age prediction through tester-age conversion to the assessment likelihood (Table G1). The 2024 and 2025 fishery age compositions use their respective independent tester-age keys applied to released FT-NIRS predictions. The 2025 source is model a00-d3. The year-specific keys also convert biological weight inputs (Table G2). Both composition series use the assessment’s identity ageing-error assumption after their selected age treatment.

Year-specific conditional keys redistribute source abundance and biomass among tester ages. Mean weights are then calculated as converted biomass divided by converted abundance, with terminal ages pooled using those totals. The partial 2024 fishery diagnostic retains unsupported source-age-13 mass (Table G3). Selected assessment weights fill that row using pooled age offsets and assign a 100% CV to the target-age-15+ weight observation. The 2025 conversion uses 668 independent tester pairs and fills the unsupported source-age-13 row with the midpoint of the age-12 and age-14 conditional probabilities. The same key supplies the 2025 age composition and weight observations (Table G4).

BTS 2025 and 2026 use separate tester-age keys. The 2026 key retains 307 pairs after excluding 22 flagged pairs, with exact TMA ages 1–18 converted before ages 15–18 are pooled into 15+. Total abundance and biomass are conserved. Converted weight SEs propagate the saved joint abundance–weight covariance (Table G5). The fitted weight model retains its existing marginal observation likelihood, and empirical-key uncertainty is excluded. Numerical checks distinguish fitted use from the retained full-pair conversion diagnostics (Table G6).

Provisional 2026 ATS ages use the BTS age–length key (ALK) applied to ATS population length-frequency estimates, followed by conversion to the TMA basis. FT-NIRS ages from the 2026 ATS samples will be available in 2027. Unsupported lengths remain unallocated. The resulting weights also supply the 2026 AVO predictions.

Fourier transform near-infrared spectroscopy (FT-NIRS) Overview

Fourier transform near-infrared spectroscopy (FT-NIRS) has emerged as an effective secondary age prediction tool and has successfully been implemented in production ageing settings (Matta and Helser, 2024), with FT-NIRS predicted ages recently being used to produce stock assessment age composition data (Dick et al., 2025; Ianelli, 2025). FT-NIRS is a non-destructive technique that interrogates a sample using light in the near-infrared region of the light spectrum (typically 4,000 to 12,000 cm-1).

Scanning with FT-NIRS produces a spectral signature of the sample based on the absorption of near infrared light by different chemical bonds, such as C-H (aliphatic), C-H (aromatic), C-O (carboxyl), O-H (hydroxyl), and N-H (amine and amide) (Murray and Williams, 1987). For otoliths, these spectra capture changes in the organic protein matrix (otolin) relative to the inorganic calcium carbonate structure. This relationship correlates strongly with fish growth and age (Passerotti et al., 2022) and has been used to develop models, calibrated with traditional microscopic ages (TMA) and FT-NIR spectra, to predict the age of unknown samples based on their spectral signatures with an estimated time-cost saving of 23-40% (Adamack et al., 2025). FT-NIRS has been applied to estimate age for a multitude of fish species from Australia (Wedding et al., 2014), the Mediterranean Sea (Basilone et al., 2024), the eastern Bering Sea (Benson et al., 2023), and the Atlantic Ocean (Adamack et al., 2025).

Traditional Microscopic Ageing (TMA) QA/QC

The FT-NIRS models rely on traditional microscopic ageing (TMA) to calibrate the model, thus the accuracy of the age predictions is directly impacted by the accuracy of the calibration ages (Chamberlin et al., 2026). The AFSC Age and Growth Program (AGP) has a long history of ageing walleye pollock by microscopic examination of otolith growth patterns (Matta et al., 2026) and has employed a rigorous quality control program since 1983 (Kimura and Anderl, 2005). In TMA of pollock, presumed annual marks (“annuli”) are enumerated from the otolith surface in younger fish or from burned or toasted otolith cross sections in older fish (Matta and Kimura, 2012; Matta et al., 2026). The accuracy of the AGP’s TMA for pollock has been independently corroborated using a variety of methods, including radiometric ageing, edge and marginal increment analysis, year-class tracking, and captive-rearing studies (Kastelle and Kimura, 2006; Kimura et al., 2006; Kimura et al., 2007; Lai, 1985).

To test FT-NIRS model prediction skill, random 20% subsamples of pollock otoliths from each collection source (fishery, bottom-trawl survey, and hydroacoustic midwater trawl) were subjected to TMA. Spectral outliers (i.e., those that predicted fish lengths outside an established threshold) were also selected for TMA; see FT-NIRS QA/QC below for more details. Each otolith selected for TMA was independently aged by two experienced readers. The TMA subsamples were evaluated for inter-reader precision and bias. All discrepancies between the two readers were resolved. Any TMA age-length outliers were reexamined, and re-aged or classified as collection errors when appropriate (Kimura and Anderl, 2005).

FT-NIRS QA/QC

In addition to the TMA QA/QC, the FT-NIR spectra underwent a three-step QA/QC process to identify poor quality spectra due to data collection errors, instrument issues, or otolith irregularities such as crystallization, contamination, or fragmentation (Goldstein et al., 2024). Spectrometer operators conducted qualitative QA/QC concurrent with data collection to identify missing data and unusual spectra using length predictions from a species- and region-specific partial least-squares regression (PLSR) model in comparison to observed lengths. Real-time length predictions were used to identify transcription errors and provide assurance of proper instrument function.

Following data collection, rigorous QA/QC was conducted to identify outliers using principal component analysis (PCA) and PLSR models developed from a multi-year collection of spectral data from each data source (AFSC groundfish survey, AFSC hydroacoustic survey, fishery data) and projections (PCA) and predictions (PLSR) of new data. PCA scores by scan date were used to visually identify instrument drift. Gross spectral data outliers were identified from PCA using Hotelling’s T2 and Q residuals (Pomerantsev and Rodionova, 2014) and PLSR outlier analyses identified discrepancies between spectra and specimen length by combining Hotelling’s T2 and Q residuals (full X-distance) and Y-distance (observed vs. predicted; Rodionova and Pomerantsev, 2020). Analyses used a threshold of 1% to identify outliers. Outliers were then aged using traditional microscopic methods. Once aged, outlier spectra were excluded from the final dataset if age predictions from the MMCNN models were also outside the MMCNN 95% Monte Carlo dropout prediction intervals discussed below.

FT-NIRS Model

Age was predicted from FT-NIR spectra using a multimodal convolutional neural network model (MMCNN). MMCNNs identify non-linear relationships in spectral data, incorporate additional inputs such as fish length or capture location, and learn relevant spectral features during training. Classical chemometric approaches such as PLS require the user to select key wavenumbers (Chen and Wang, 2019). The MMCNN used here is an updated version of the MMCNN presented in Benson et al. (2023) and Chamberlin et al. (2026). The MMCNN includes one convolutional layer and six dense layers to predict age from spectral and fish-length data.

The first layer of the MMCNN is the spectral input data which is fed to a 1D convolutional layer, which acts as an automated feature extractor to identify patterns in the spectra. This output is then processed with a Rectified Linear Unit (ReLU) activation function to introduce nonlinearity into the network necessary for approximating continuous functions (Brownlee, 2019; Géron, 2019). The data are then flattened into a one-dimensional array and passed through a dense layer (all dense layers use Exponential Linear Unit (ELU) activation). This reduces the dimensionality of the spectral input and balances its contribution relative to the metadata. The metadata input is fed to a dense layer, then concatenated with the spectral input layer. The output is passed through a fully connected dense layer with ELU activation to model the interactions between spectral data and metadata. To mitigate overfitting, 5 dropout layers follow each dense layer to randomly ignore a subset of neurons and prevent codependency between nodes (Srivastava et al., 2014). Crucially, these dropout layers remain active during the inference phase, a technique known as Monte Carlo (MC) dropout, allowing the model to perform multiple forward passes per sample to generate a distribution of age estimates and calculate Monte Carlo prediction intervals. Finally, a fully connected dense layer with a single node and a batch normalization layer are used to produce a continuous age estimate, allowing for loss estimation via a Mean Absolute Error (MAE) function. The model’s hyperparameters (the number of filters in the convolutional layer, the number of nodes in the concatenated layer, learning rate, batch size and the dropout rate) were optimized using hyperband optimization (Li et al., 2018) with early stopping.

The walleye pollock model is trained on spectra and TMA ages from 2014-2025 using an “n−1” annual model updating approach. Under this scheme, spectral and age data from all fleets up to the year prior to the target prediction year are included (for example, predicting 2025 fishery ages uses data from 2024 and earlier). For MMCNN training, input data are first split into development (80%) and testing (20%) pools using a randomly shuffled split that is stratified on fleet and year. Samples receive a normalized weighting score based on 2 coefficients: decay is an integer [1, 2, 3] that defines the rate of exponential decay for samples based on year, and alpha [0, 0.1, 0.2, …, 1.0] defines whether sample year or sample age frequency has more influence in weighting the sample, with alpha = 1 turning decay off. This allows for testing of whether model performance improves when more recent calibration data or rare age classes are weighted more heavily. For hyperparameter optimization, the development data are further split into training (90%) and validation (10%) datasets to inform early stopping, using the previously defined sample weights. For each scenario a series of 10 trainings, with random seeds, are run to estimate the median number of epochs needed to train the model but avoid overfitting, prior to a final training run based on the median number of epochs.

In total, 31 training models were produced with a grid search for the 2 sample weighting coefficients, and age predictions were generated for bottom trawl survey, hydroacoustic survey and fishery fleets. The final candidate model for each fleet was selected using four statistical metrics: Lin’s concordance correlation coefficient (Lin’s CCC), the mean Winkler score, R2, and the slope of the regression between FT-NIRS predicted ages and corresponding TMA ages. Lin’s CCC measures how closely the observed data aligns with a 45° line of perfect agreement, while the mean Winkler score evaluates average performance based on the width of the Monte Carlo prediction intervals and the frequency of samples falling outside them. The four metrics capture different aspects of model accuracy, and visual assessments complemented them. Ultimately, the best-performing model was identified by synthesizing these visual and quantitative criteria. Age predictions were then finalized by removing any samples that were both flagged as a spectral outlier and an outlier from the Monte Carlo prediction intervals. This finalized dataset was then transmitted to end users and coded as FT-NIRS predicted ages.

Age conversion and assessment use

The assessment uses year-specific independent tester TMA conversions for the 2024 and 2025 fishery compositions, matching annual weight conversions and separate survey-specific age conversions (Table G1). These treatments serve different purposes: predicting age from spectra, allocating abundance and biomass among ages, and specifying the assessment likelihood are separate steps. Current input and fit records establish their use; the retained partial-conversion diagnostics describe their original support and uncertainty limits.

The 2026 BTS conditional tester-age key excludes calibration pairs marked nir_outlier = Y, removing 22 of 329 complete pairs and retaining 307. It targets independent test_age conditional on FT-NIRS final_nir_age; each FT-NIRS row is normalized by its retained paired count. Conversion uses exact TMA ages 1–18 before pooling ages 15–18 into 15+. Screening applies to calibration pairs, preserving the released abundance vector. All unflagged complete pairs are eligible, including checks outside the systematic 20% sample.

Screening changed the exact mean converted age from 5.318978 to 5.316448 years, with a largest age-proportion change of approximately 0.124 percentage points and unchanged total abundance. The same 307-pair key supplies BTS weight means and their joint-covariance delta-method SEs, provisional ATS age allocations and biomass-derived weights, and the 2026 AVO prediction weights. The standalone RE-WAA refit and assessment fits using these inputs are complete S10. The 2025 BTS key is unchanged. The original 329-pair products remain historical evidence. Empirical-key uncertainty is excluded; the fitted weight model retains its existing marginal observation likelihood rather than using the full converted covariance as a new likelihood.

The contribution describes 31 MMCNN training candidates, distinguished by sample-weight settings and fleet-specific selection. PCA and PLSR provide spectral QA/QC; PLSR also provides length predictions. The a00-d3 and a03-d1 labels on the saved 600-fish comparison identify prediction sets, separately from the assessment’s cumulative 0.x input sequence.

Table G1 FT-NIRS Use and Transformations by Data Source and Year
Gear or survey Collection year Input or model version Age basis and year-specific key Application and verified status
Commercial fishery, pelagic trawl (NORPAC gear 2) 2024 Saved sampler_2024_2025_20261016T160737Z; current fishery CAA Released FT-NIRS ages; distinct 2024 key recovered from the earlier release: 2,985 released records and 693 independent tester pairs. Specimen/age-field hashes match the original-release verification record. The ordinary assessment uses the independent tester TMA composition key, with the source-age-13 row completed from pooled 2024 source-age offsets at ages 9–12 (34 pairs) and likelihood N=578. The selected weight input uses the same key and a 100% CV for the target-age-15+ observation. The retained partial weight diagnostic describes its historical supported-only scope. The accepted marginal Model 26.1.2 fit uses the same year-specific composition and weight inputs. S2, S3, S6, S10.
Commercial fishery, pelagic trawl (NORPAC gear 2) 2025 FT-NIRS model a00-d3; annual catch-at-age expansion Independent tester TMA ages; year-specific conditional key from 668 complete pairs. The unsupported source-age-13 row is the midpoint of the age-12 and age-14 rows. Converted proportions use ages 1–14 and 15+ with selected likelihood N = 530 and identity ageing error. Total numbers are preserved. The matching weight observations use the same key. Key and interpolation uncertainty are additional to sampling uncertainty. S1, S2, S3, S10.
Commercial fishery, pelagic trawl 2025 Matching annual weight observations Same independent tester-age key and source-age-13 midpoint. Source age 1 has zero abundance. The key redistributes abundance and biomass in each of 1,000 saved bootstrap draws; weight ratios and SDs are calculated from the converted quantities. These observations supply the selected fitted weights. Target ages 13 and 14 have no converted abundance. Empirical-key and interpolation uncertainty are excluded. S3, S10.
Bottom-trawl survey (BTS), EBS/NBS 2025 Revised tinyVAST_abundance.csv / tinyVAST_props.csv; saved bts_2026_candidate lineage FT-NIRS age estimates; bts_2025 independent tester key, dated 2025-09-24, 390 pairs. Converted abundance and age proportions are used in the working assessment. Exact TMA ages 1–18 are converted before ages 15–18 are pooled into 15+. This key transfer supplies no additional abundance SE or empirical-key uncertainty. The earlier candidate exclusion is retained only in the historical staging record. S1, S4, S6, S10.
Bottom-trawl survey (BTS), EBS/NBS 2026 Revised spatial estimates; screened 29 October rerun input Independent test_age conditional key from the 2026-09-24 release: 329 complete pairs before screening, 307 after excluding 22 nir_outlier = Y pairs. Screened key applied to working CAA and WAA inputs. Exact TMA ages 1–18 are converted before 15+ pooling; source abundance, sample-size choices and 2025 key are retained. Original full-pair products are retained unchanged. S1, S4, S10.
Bottom-trawl survey, Indivero/VAST weight products 2025 and 2026, converted separately Saved VAST joint N/W covariance; 29 October screened-key preparation and standalone RE-WAA refit The 2025 full tester key is retained; 2026 uses the screened 307-pair key with the matching VAST abundance and weight estimates. Ratios and delta-method SEs use abundance–weight and cross-age/year covariance under the same method. Nine 2026 observation means and nine SEs change; 2025 observations remain unchanged. The standalone RE-WAA numerical checks pass. Empirical-key uncertainty is excluded. S3, S5, S10.
BTS historical age-comparison material 2014–2018 FTNIR Compare.qmd uses historical fishery/survey paired releases Historical comparison data span 2014–2018. The new contribution describes training data spanning 2014–2025 with annual n−1 updating. These series use different data updates. The historical comparison files alone do not establish the precise training set/model ID used for each 2025/2026 release; do not transfer old keys to new years. S7, contribution above.
Acoustic-trawl survey (ATS), acoustic expansion with trawl biological samples 2024 ATS_2024_age comp ALK.xlsx, length totals × age-length proportions The preparation record quotes the 2025-09-08 email as TMA ages sent to MACE. The workbook has a 2024 age-length pivot and matrix multiplication of expanded numbers/biomass. This local workbook verifies a length-to-age step, not an automatic FT-NIRS designation. A separate ATS age-age conversion and exact predictive model/key lineage are unverified here. S3, S8.
Acoustic-trawl survey (ATS) 2026 ATS/stock_assessment_output/*202604.csv; 29 October provisional rerun products Released BTS FT-NIRS length key followed by the screened 307-pair BTS conditional tester-age key; source FT-NIRS allocations and unsupported lengths are preserved. Abundance and biomass are redistributed with the same key; pooled ratios supply ATS and 2026 AVO prediction weights. Provisional estimates are used in the completed working fits and await direct ATS age-composition data in 2027. Transfer assumptions and uncertainty scope remain unchanged. S9, S10.

Note. FT-NIRS use and transformations by collection and year. Current fitted applications are distinguished from retained historical preparation diagnostics. Unfiltered counts describe the original complete released tester pairs; the 2026 screened input excludes the 22 flagged complete pairs.

The original keys contain 693 and 668 pairs for fishery 2024 and 2025, and 390 and 329 for BTS 2025 and 2026 before screening. The current 2026 BTS key retains 307 pairs. The fishery gear label follows the saved NORPAC records: gear 2 is PELAGIC in both 2024 and 2025. The contribution’s fishery, bottom-trawl survey and hydroacoustic categories retain their own age basis and sampling conditions.

Predictive model and assessment input differences

The MMCNN combines spectral and fish-length information, MC dropout prediction intervals, hyperband optimization and 31 sample-weight settings. Its annual n−1 updating rule uses information available before the prediction year; for example, a 2025 prediction uses data through 2024. The selected fleet-by-year model checksum, coefficient setting and exact mapping to the saved 600-fish prediction files remain to be documented.

The full tester-key release uses final_nir_age as predictor and independent test_age as target, excluding resolved final_age as the calibration target. It contains 3,000 fishery-2025 records, 1,638 BTS-2025 records and 1,586 BTS-2026 records; 2,992, 1,619 and 1,582 have released FT-NIRS ages. Their complete-pair counts are 668, 390 and 329, respectively; the screened 2026 BTS application retains 307 S1.

For the 2025 fishery, model a00-d3 FT-NIRS ages are converted to independent tester ages using the 668 complete paired observations. The conditional probability of tester age jj given FT-NIRS age ii is Kij=nij/∑jnijK_{ij}=n_{ij}/\sum_j n_{ij}. Converted numbers are NjTMA=∑iNiFTNIRKijN^{\mathrm{TMA}}_j=\sum_i N^{\mathrm{FTNIR}}_iK_{ij}. Empirical rows retain the released paired observations, including flagged pairs. The unsupported source-age-13 row is K13,j=(K12,j+K14,j)/2K_{13,j}=(K_{12,j}+K_{14,j})/2, giving probabilities of one third at tester age 10, one sixth at age 11 and one half at age 15. The age-12 row has six pairs and the age-14 row one pair, so this interpolation has limited direct support. Source and tester ages in the release are exact ages 2–15; the assessment terminal group contains ages 15 and older. The selected likelihood sample size is 530. The key is treated as fixed; empirical-key and interpolation uncertainty are excluded.

The 2024 fishery composition uses its 693-pair independent tester key. The unsupported source-age-13 row uses pooled TMA-minus-FT-NIRS offsets from the same year’s source ages 9–12 (34 pairs). Empirical rows remain unchanged; the selected likelihood input is 578. Both recent years are converted before fitting and use a 15-by-15 identity ageing-error matrix, equivalent to the ADMB setting with ageing error switched off. Key and tail-allocation uncertainty are additional to the sampling precision represented by the selected likelihood weights.

Weight conversion applies the same conditional key to source numbers and biomass, then divides converted biomass by converted numbers. Terminal-age weights use pooled totals. The partial empirical 2024 diagnostic leaves unsupported source-age-13 mass unallocated. The selected weight treatment fills that row using pooled offsets from source ages 9–12 and assigns a 100% CV to the target-age-15+ observation. Those fixed approximations add no empirical calibration pairs; their uncertainty differs from a sampling SE. The 2025 weight observations use the same source-age-13 midpoint as the age composition. Their zero-abundance source-age-1 padding contributes no converted numbers or biomass. The midpoint is specific to 2025; source age 14 also lacks pairs in the 2024 key.

The older staging record S6 describes a 2024 endpoint in pm_26_candidate.dat: fishery CAA at 0.4, provisional BTS WAA/biomass at 0.5/0.6, ATS at 0.7, and separate AVO-only 0.8/0.9 components. These are historical input-sequence labels from the incremental-model plan. Current fitted use follows the documented working input and run records, not those earlier staging exclusions.

Source and validation limits

The partial 2024 empirical diagnostic retains its unsupported source-age-13 mass. Selected assessment weights use the pooled-offset rule and 100% CV described above. The 2024 and 2025 compositions use their respective tester-age keys and selected support rules. Weight SEs propagate the available joint abundance–weight covariance, while the fitted model retains its marginal observation likelihood. Empirical-key uncertainty remains excluded.

The assessment author identified a00-d3 as the selected 2025 fishery model. The exact training-run checksum, coefficient setting and complete collection-by-year release record remain to be documented. The 31 predictive candidates and the assessment’s cumulative input stages identify different choices. The earlier mixed-basis BTS workbook remains unavailable; the separately identified current workbook is excluded from assessment assembly. Its source basis must be established before using it in a comparison.

Provisional ATS products retain their transferred BTS age–length and tester-age keys, unsupported-length limits and separate sampling conditions. Direct ATS age and weight validation remains open, with age-composition data expected in 2027. Archived full-pair calibration products remain available alongside the screened-key input records. Prior fit, projection and posterior records retain their original dates and input identities. Final model and recommendation selection remain separate review decisions.

Sources and reproducibility

The paired-age releases, preparation products and current run records retain their source identities. Detailed file locations, checksums and the original preparation narrative are preserved in the technical source record.

  • S1 — Paired tester-age release: the full year-specific tester-key workbook and tidy release, with independent tester ages as the calibration target.
  • S2 — Fishery observations: catch-expanded annual numbers based on released FT-NIRS ages, with year-specific tester-age conversions: 693 pairs and N=578 for 2024; 668 pairs and N=530 for 2025.
  • S3 — Weight conversion: year-specific fishery conversion keys, partial 2024 diagnostics and independent fishery arithmetic checks.
  • S4 — Survey age compositions: revised BTS abundance and proportion estimates, with their source age assignments.
  • S5 — Survey weights and covariance: matching model-based abundance and weight estimates, joint covariance and delta-method validation.
  • S6 — Historical staging: the earlier preparation sequence, retained separately from current selected input and fit records.
  • S7 — Earlier age comparison: fishery and survey comparisons for 2014–2018, distinct from later training and prediction releases.
  • S8 — ATS length-to-age calculation: the 2024 age–length workbook and expanded number/biomass calculations.
  • S9 — ATS survey products: regional survey length and biomass products used for the provisional BTS-key transfer.
  • S10 — Current screened-key inputs and fits: the 307-pair calibration, completed standalone RE-WAA refit and current assessment run records. The original 329-pair products retain their historical identity.

Year-specific weight-conversion diagnostics

The retained full-pair conversion record separates three completed year-specific conversions from the partial 2024 fishery diagnostic (conversion-status table). Fishery 2025 and BTS 2025–2026 use independent tester-age keys; positive unsupported source-age-13 mass remains unallocated in fishery 2024.

Mean weights generally increase with age, with the largest source-versus- converted differences concentrated at older ages (2024 fishery weight table). The partial fishery 2024 values at TMA ages 13 and 14 are both 1.2878 kg, while its target 15+ weight remains missing. Its prepared older-age SEs are large relative to the means; the partial converted SDs condition on the fixed key and supported source ages.

The 2025 fishery conversion raises the 15+ mean from 0.8102 to 1.2676 kg; target ages 13 and 14 retain missing weights because converted abundance is zero (fishery weight comparison). Thus the older-age differences include changes in support as well as in ratios.

BTS 2025 converted weights are generally below the source weights from age 5 upward; in 2026, weights at ages 3–8 remain close to or above their source values, while older-age weights are lower (BTS weight comparison; Figure G1). The 15+ mean changes from 1.7646 to 1.5474 kg in 2025 and from 1.8390 to 1.3665 kg in 2026. These are conversion contrasts that vary by age and year. The smaller conditional SEs in several converted cells retain the stated fixed-key uncertainty scope.

Independent fishery arithmetic, preservation of earlier fishery values and survey covariance/derivative checks establish computational consistency (conversion checks). The partial 2024 diagnostic leaves unsupported source-age-13 mass unallocated. Current selected weights use the separate pooled-offset tail treatment and 100% CV, and the screened-key standalone RE-WAA and assessment fits are complete. These distinctions preserve the historical diagnostic’s support limits and the current fit’s fixed-key uncertainty scope.

Adjustments to FT-NIRs for assessment application

The following tables retain the full-pair calibration used to evaluate conversion arithmetic, including the partial 2024 fishery results. Current assessment inputs use the separately documented selected tail treatment and screened 2026 key. The table values preserve their original calibration basis.

Complete conversion report, including Table 3 for fishery 2024–2025

Diagnostic basis and current use

The retained diagnostics convert fishery 2025 and BTS 2025–2026 abundance and biomass with their year-specific independent tester-age keys. Fishery 2024 has a distinct 693-pair key, but its empirical partial conversion leaves positive source-age-13 mass unallocated. The selected assessment weight treatment fills that row using pooled offsets from source ages 9–12 and assigns a 100% CV to the target-age-15+ weight observation. The current standalone RE-WAA refit and assessment fits are complete; the historical partial diagnostic remains separate. The BTS tables below retain the original full-pair calibration, while the current 2026 fit uses the screened 307-pair key.

Table G2 Conversion Status by Data Source
Stream Conversion key Current action
Fishery 2024 Distinct 2024 key: 693 pairs Partial diagnostic; source age 13 unallocated
Fishery 2025 2025 fishery tester-age key: 668 pairs Converted with two approved probability rules
BTS 2025 2025 BTS tester-age key: 390 pairs Converted with joint model uncertainty
BTS 2026 2026 BTS tester-age key: 329 pairs Converted with joint model uncertainty

Note. Conversion status by new data source.

Conversion and approved approximations

Each key gives the distribution of TMA tester age conditional on FTNIR age. Abundance and biomass are redistributed together, using the same conditional probabilities. Converted mean weight is converted biomass divided by converted abundance. Within a source FTNIR bin, this calculation assigns the same source mean weight to every target age.

For fishery 2025, Jim approved two rules for unsupported source ages:

  • Age 1: a dummy identity row assigns FTNIR age 1 to TMA age 1. All saved source age-1 catch estimates are zero, so this row retains zero catch.
  • Age 13: each target-age probability is the arithmetic average of its probabilities in the source age-12 and age-14 rows. The resulting row sums to one. This approximation uses the existing age-12 and age-14 pairs.

Converted target-age 13 and 14 abundances are zero in the 2025 fishery key. Their weights and SEs remain paired missing observations. The historical data continue to inform these ages in the future wtAgeRE fit. All pre-2025 fishery mean/SE decimal values are preserved exactly.

Exact BTS target ages 1–18 are retained during conversion. Target ages 15–18 are then pooled into 15+, conserving total abundance and biomass. The 2024 fishery key also retains exact target ages through 18; the 2025 fishery key has target ages through 15. The same terminal pooling convention applies. Age selection for wtAgeRE occurs after conversion; its input bins are 3–15+.

Fishery 2024 results and remaining gap

The recovered 2024 release contains 2,985 released FTNIR ages and 693 complete independent tester pairs. The target is test_age; the resolved final_age is a separate field. Canonical specimen and age-field hashes match the independent original-workbook verification record. The original workbook itself remains outside this local snapshot. The empirical key uses all complete released pairs, including additional QA/QC selections; their representativeness remains an assumption.

Source ages 1–12 have empirical probability rows. Source ages 13–15 lack pairs; only age 13 has positive mass in the saved sampler draws. Its unallocated observed-point mass is 0.0323% of abundance and 0.0817% of biomass. Allocated plus unallocated totals balance across all 1,001 saved rows to relative errors below 6.7e-16. The diagnostic retains that mass separately and preserves the original totals.

The table and figure report the partial, fixed-key bootstrap mean and SD from the supported source rows. Every converted 2024 bin remains conditional on the unresolved source-age-13 allocation. Target TMA age 15+ receives zero allocated abundance, so its mean and SD remain missing. Source FTNIR age 13 and target TMA age 13 are distinct: supported source ages can populate target ages 13 and 14.

The 2025 midpoint rule stays specific to its approved key. In 2024, source age 14 also lacks calibration pairs; applying the age-12/14 midpoint rule would require additional empirical support. The 2024 key supports source age 1 directly; its positive source catch is retained.

Table G3 Fishery 2024 Weights and Partial Supported-Only Conversion
Age Prepared mean Prepared SE Partial TMA mean Partial TMA SD
3 0.3832 0.0093 0.4353 0.0053
4 0.4841 0.0067 0.4807 0.0033
5 0.5317 0.0035 0.5596 0.0021
6 0.6628 0.0040 0.6175 0.0023
7 0.8195 0.0166 0.6965 0.0060
8 0.9733 0.0439 0.8252 0.0138
9 0.9850 0.0469 1.0162 0.0182
10 1.1167 0.0401 1.0163 0.0227
11 1.3455 0.0774 1.0774 0.0227
12 1.2878 0.1082 1.2464 0.0455
13 0.7485 0.7800 1.2878 0.1082
14 1.1658 0.6356 1.2878 0.1082
15+ 0.9705 0.9011 Missing Missing

Note. Fishery 2024 weights in kilograms: preserved prepared values and partial supported-only conversion. SDs are conditional fixed-key diagnostics; all converted bins remain incomplete.

Weight and uncertainty comparisons

Four panels compare weight in kilograms by age for fishery 2024 and 2025, BTS 2025, and BTS 2026. Distinct line types and point shapes distinguish prepared FTNIR and converted TMA estimates. The 2024 partial conversion lacks target age 15 plus; the 2025 conversion lacks target ages 13 and 14. Tables provide values and uncertainty.

Note. Mean weights before and after conversion, with source SEs and converted bootstrap SDs or survey SEs. Fishery 2024 shows a partial supported-only diagnostic; source-age-13 mass remains unallocated.

Figure G1 Mean Weights Before and After Conversion

Converted fishery weights and bootstrap SDs are recalculated from the first 1,000 paired sampler bootstrap draws after transforming each draw’s abundance and biomass. The final observed-data point row is excluded from those summaries. The previously selected legacy convention is retained: a target age absent in a bootstrap draw has zero weight for that draw. The SD uses the sample denominator. Known limitations of the legacy sampler’s resampling selectors remain in the source record.

BTS uncertainty uses the saved joint VAST parameter covariance and conditional random-effect covariance. It includes dependence between source abundance and weight, among ages through shared parameters, and between 2025 and 2026. The ratio’s numerator and denominator both contribute to the delta-method SE. The calculation evaluates the saved VAST model at its parameter estimates.

All conversion keys are treated as fixed. The reported SEs exclude uncertainty in the empirical keys, the dummy row, and the interpolated row.

Table G4 Fishery 2024–2025 Weights and Uncertainty
Year Age Original mean Original SE TMA mean TMA SE / SD
2024 3 0.3832 0.0093 0.4353 0.0053
2024 4 0.4841 0.0067 0.4807 0.0033
2024 5 0.5317 0.0035 0.5596 0.0021
2024 6 0.6628 0.0040 0.6175 0.0023
2024 7 0.8195 0.0166 0.6965 0.0060
2024 8 0.9733 0.0439 0.8252 0.0138
2024 9 0.9850 0.0469 1.0162 0.0182
2024 10 1.1167 0.0401 1.0163 0.0227
2024 11 1.3455 0.0774 1.0774 0.0227
2024 12 1.2878 0.1082 1.2464 0.0455
2024 13 0.7485 0.7800 1.2878 0.1082
2024 14 1.1658 0.6356 1.2878 0.1082
2024 15+ 0.9705 0.9011 Missing Missing
2025 3 0.4354 0.0217 0.3143 0.0115
2025 4 0.5753 0.0102 0.5559 0.0085
2025 5 0.6356 0.0063 0.6214 0.0066
2025 6 0.6891 0.0050 0.6929 0.0027
2025 7 0.7913 0.0086 0.7295 0.0029
2025 8 0.8824 0.0175 0.8555 0.0073
2025 9 1.0084 0.0296 0.9657 0.0115
2025 10 1.0939 0.0411 1.1395 0.0292
2025 11 1.1054 0.0557 1.1943 0.0406
2025 12 1.4336 0.1344 1.0815 0.0241
2025 13 1.3513 0.6052 Missing Missing
2025 14 1.1133 0.6965 Missing Missing
2025 15+ 0.8102 0.8284 1.2676 0.0950

Note. Fishery 2024–2025 weights and uncertainty in kilograms. The 2024 TMA results are a partial supported-only conversion; source-age-13 mass remains unallocated. Missing target ages have no converted abundance.

2024: partial bootstrap mean and fixed-key SD, conditional on the supported source ages; target age 15+ remains missing. 2025: converted mean and bootstrap SE.

Table G5 BTS Mean Weights and Standard Errors After Joint Covariance Propagation
Year Age Original mean Original SE TMA mean TMA SE
2025 3 0.3655 0.0357 0.2255 0.0161
2025 4 0.4928 0.0352 0.5260 0.0166
2025 5 0.5951 0.0186 0.5871 0.0134
2025 6 0.6964 0.0114 0.6758 0.0098
2025 7 0.8329 0.0206 0.7340 0.0100
2025 8 0.9690 0.0331 0.8125 0.0125
2025 9 1.0288 0.0325 0.9026 0.0131
2025 10 1.1360 0.0383 1.0872 0.0197
2025 11 1.2675 0.0653 1.0659 0.0200
2025 12 1.4825 0.0943 1.1496 0.0257
2025 13 1.4562 0.1232 1.2577 0.0358
2025 14 1.7453 0.2714 1.3987 0.0558
2025 15+ 1.7646 0.3427 1.5474 0.0834
2026 3 0.3850 0.0291 0.3971 0.0190
2026 4 0.5211 0.0184 0.5440 0.0155
2026 5 0.6188 0.0218 0.6400 0.0165
2026 6 0.7139 0.0237 0.7254 0.0109
2026 7 0.7551 0.0162 0.8076 0.0101
2026 8 0.8707 0.0144 0.8755 0.0101
2026 9 1.0041 0.0203 0.9476 0.0125
2026 10 1.1782 0.0322 1.0064 0.0132
2026 11 1.3129 0.0472 1.0415 0.0156
2026 12 1.4490 0.0762 1.2159 0.0209
2026 13 1.9177 0.1171 1.3719 0.0298
2026 14 1.6711 0.1496 1.5171 0.0648
2026 15+ 1.8390 0.1928 1.3665 0.0336

Note. BTS mean weights and SEs in kilograms after propagating the joint model covariance.

Validation and source record

Table G6 Validation of the Transformations
Check Result
Fishery independent recalculation PASS
Pre-2025 fishery decimal preservation Pass
Survey source SE reconstruction: largest relative difference 1.22e-15
Ratio derivative check: largest scaled difference 1.68e-11
Analytic versus numerical converted SE: largest relative difference 3.15e-11
Survey random-effect gradient: maximum 4.36e-12
Saved survey fixed Hessian positive definite Yes
2024 specimen/age-field identity and partial arithmetic Pass: 22 checks; positive source-age-13 support unresolved
Input adapter Selected inputs used in completed working fits; historical partial-conversion support limits retained
wtAgeRE optimization Screened-key standalone RE-WAA fit complete; earlier partial-conversion branch remains a separate diagnostic

Note. Validation of the transformations. Numerical checks retain the full-pair conversion basis; current fitted inputs use the selected 2024 tail treatment and screened 2026 key.

The source records retain matching abundance and weight estimates from the same saved survey fit, along with input/output hashes and fixed-key approximation rules. The empirical key is treated as fixed. Current fitting records and the historical conversion diagnostics are identified separately in the technical source record.

The historical 2024 partial-conversion diagnostics preserve their original inputs and supported-age limits. The current selected tail allocation, screened BTS key and completed fits have separate source and run identities. Earlier preparation states and the original verification wording remain archived in the technical source record.

This is an internal methods record. It uses a compact Quarto report and TAF-compatible source, transformation, output, and provenance stages. Assessment adoption is documented in the separate input and run records.

  • Historical partial-diagnostic fishery input: converted 2025, preserved 2024
  • Converted BTS input
  • Fishery approximation key
  • Conversion manifest
  • BTS uncertainty validation
  • 2024 empirical key
  • 2024 partial bootstrap summaries
  • 2024 exact and pooled point candidates
  • 2024 key support and unallocated source mass
  • 2024 validation

Complete numbered conversion report · Editable analytical Quarto source · Subsection source manifest

Provisional ATS age compositions

In 2026, ATS age compositions were estimated by borrowing the BTS age–length keys and applying them to ATS abundance-at-length data. Following usual practice, age data for the 2026 ATS length samples will be applied in 2027.

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Appendix H
BTS Spatiotemporal Biomass Index and Abundance at Age, Including the Northern Bering Sea

This appendix describes the spatiotemporal modeling approach used to estimate the bottom-trawl survey (BTS) biomass index and abundance at age for the combined eastern and northern Bering Sea (EBS and NBS). This approach was adopted in the 2024 assessment for both abundance at age and survey indices and follows the approach used by the AFSC Groundfish Assessment Program (GAP) in previous assessments. The sections below describe its application to the 2026 survey data, including model specifications and uncertainty estimates.

Scope and relationship to the earlier VAST appendix

The earlier VAST appendix describes a different software generation and mixed 1982–2023/2024 coverage. It is retained as a historical source. The description uses the settings in the saved production fit objects. The saved production fit objects identify sdmTMB 1.0.0 for the biomass index and tinyVAST 1.6.3 for abundance at age. Model-based integration across EBS and NBS extends the approach used to address pollock distribution shifts (O’Leary et al. 2020). The sdmTMB framework is described by Anderson et al. (2022).

Both output series contain 44 years, 1982–2019 and 2021–2026. The survey was absent in 2020. The index fit retains 2020 as an additional latent time step representing a model prediction. The age fit retains annual time levels across 1982–2026, while the abundance and composition data files omit 2020. NBS sampling coverage varies among years within the prediction domain.

Biomass index

The pollock index code reads density-dependence-corrected station biomass density from the VAST-named input file. The file name is historical; the saved model class is sdmTMB. Input density is converted from kg/ha to kg/km² by multiplying by 100. The saved fit uses a Poisson-link delta-gamma observation model with separate year effects and spatial and spatiotemporal fields. Both components have spatial fields and annual AR(1) spatiotemporal structure. The retained call enables geometric anisotropy and includes a spatially varying coefficient for the environmental covariate.

The companion pollock code defines that covariate as standardized cold-pool area, the area of bottom water at or below 2°C (Rohan et al. 2022). The saved object contains its numerical covariate and the formula; the complete annual cold-pool release manifest remains unavailable. The exact environmental release and production script revision require confirmation.

Predicted density is integrated over a fixed regional grid. For grid-cell area (A_{r,j}) in km² and predicted biomass density (d_{t,j}) in kg/km², the regional biomass index in tons is

Îr,t=11000∑j∈rAr,jd̂t,j.(20) \widehat I_{r,t}=\frac{1}{1000}\sum_{j\in r}A_{r,j}\widehat d_{t,j}. \qquad(20)

The biomass-index estimates include separate EBS, NBS and combined Both products. The combined 2026 point estimate is 9,034,017.809 t; the separate EBS and NBS point estimates sum to that value within numerical precision. These survey estimates remain subject to assessment input selection and acceptance.

Abundance at age

The saved tinyVAST fit uses numerical density at station and age, with age-by-year fixed effects in both delta components. All 15 labelled age classes have age-specific spatial variance terms and a common estimated lag-1 temporal coefficient in the spatiotemporal specification. The saved control has anisotropy disabled. This model uses age-by-year effects with the environmental terms excluded.

The companion pollock code multiplies CPUE_num by 100, converting fish/ha to fish/km². Its comment describing this as a conversion of kg is inconsistent with the numerical input; the calculation is an abundance calculation. Numerical density is integrated over the combined EBS–NBS grid and scaled to billions of fish:

N̂r,t,a[billionfish]=1109∑j∈rAr,jn̂t,a,j,p̂r,t,a=N̂r,t,a∑bN̂r,t,b.(21) \widehat N_{r,t,a}\;[\mathrm{billion\ fish}] =\frac{1}{10^9}\sum_{j\in r}A_{r,j}\widehat n_{t,a,j}, \qquad \widehat p_{r,t,a}= \frac{\widehat N_{r,t,a}}{\sum_b\widehat N_{r,t,b}}. \qquad(21)

The abundance-at-age matrix contains 15 rows and 44 year columns. Its row order agrees with the companion age_1 through age_15 composition columns: normalizing every matrix column reproduces the composition file to a maximum absolute difference of (8.4^{-16}). The 2026 combined total is 16.064690 billion fish. The companion composition file supplies the age labels for the matrix and must remain attached to it. Displayed ages are 1–14 and 15+; the terminal category represents fish aged 15 and older. The original source column names are retained in the data. The age export supplies only the combined EBS–NBS estimates (terminal-age interpretation).

These expanded compositions use the age assignments and age–length-key preparation in their station-level inputs. Age assignment and FT-NIRS-to-traditional-age conversion precede the tinyVAST expansion. The exact release, assignment rules for 2025–2026, and any age-age correction used in this production input remain part of the source reconciliation.

Verified settings and prediction-code evidence

The retained index fit uses 250 interior mesh knots, anisotropy and a spatially varying environmental coefficient; the age fit uses 50 interior knots with anisotropy disabled and a separate spatial variance structure by age (Table H1). Prediction-grid and integration settings are identified separately as companion-code evidence. The local code checkout is 2a9e6f26062d34ee0375f8eac9462e51273e65a3. Its default species selections are Pacific cod for the index and yellowfin sole for age compositions. The saved pollock fit objects supply the production evidence for this appendix; the generic default selections remain code context.

Table H1 Delivered 2026 Pollock Fit and Companion Prediction Settings
Setting Biomass-index fit Abundance-at-age fit
Platform and retained version sdmTMB 1.0.0 tinyVAST 1.6.3
Response Biomass density Numerical density by age
Observation family Poisson-link delta-gamma Poisson-link delta-gamma
Fixed effects Year in both components Age × year in both components
Spatial mesh 250 interior knots; 307 total vertices 50 interior knots; 106 total vertices
Spatiotemporal structure AR(1) in both components Shared lag-1 coefficient; age-specific variance structure
Environmental coefficient Spatially varying coefficient for env None retained
Anisotropy Enabled in saved call Disabled in saved control
Observation years 1982–2019, 2021–2026 1982–2019, 2021–2026
Saved input rows 17,236 265,350 station–age rows
Reported output regions EBS, NBS, Both Both
Prediction grid in companion code 5 nmi; 1,578 EBS + 672 NBS cells Same combined 2,250-cell grid
Integration bias/SE settings in companion code get_index: bias_correct=TRUE apply.epsilon=TRUE; bias.correct=FALSE; getsd=FALSE

Note. Retained settings in the 2026 pollock fit objects, with prediction-grid and integration settings identified separately as companion-code evidence. The complete production prediction record remains unavailable.

The code grid has 492,989.921 km² in the EBS and 198,866.805 km² in the NBS, summing to 691,856.726 km². Those grid files are hashed in the source record. The complete production prediction grid and expansion invocation remain unavailable. This draft therefore distinguishes companion-code settings from verified saved-fit settings. The historical 2-nmi grid and 750-knot index describe the earlier VAST workflow.

Uncertainty, diagnostics and outstanding review

The index code requests bias-corrected integration. It also contains a 500-simulation covariance workflow. The assessment selects its covariance file and uncertainty treatment separately from those integration settings. The age expansion code sets bias.correct=FALSE and getsd=FALSE despite apply.epsilon=TRUE. Its age output therefore excludes epsilon bias correction and a full estimated age-composition covariance. Assessment weighting and the selected design-based covariance remain separate decisions.

The saved index object reports a positive definite Hessian and maximum absolute retained gradient 0.0138148. The saved age object reports optimizer return code 0, a positive definite Hessian and maximum retained gradient 0.000205084. These diagnostics require provider review for numerical acceptance. Both gradients exceed the workspace’s (10^{-4}) assessment-model convergence guardrail; their suitability for these survey fits requires provider review. This appendix uses the saved survey fits by the provider.

The saved index data have 17,236 rows, while the adjacent raw index export has 17,237; the counts differ in 2026 (350 versus 351). The saved age fit has 265,350 rows, versus 258,555 in the adjacent age-density export. Historical differences occur in 1982, 1985, 1988, 1991, 1994, 2001, 2005, 2006 and 2018; 2026 has 5,250 fitted rows versus 5,265 exported rows. These differences prevent a claim that the saved objects exactly reproduce the neighboring raw files. Their causes, the intended final input versions and the fit-to-export chain require confirmation from the survey analysts.

Before finalizing this appendix, confirm the production script revision, prediction grid, annual environmental release, full R/TMB/dependency versions, age-assignment lineage, treatment of the input mismatches, and the accepted covariance and diagnostic assessment. The latest linked general writeup and terms-of-reference table remain unavailable through the connected source. Their agreement with this draft requires author review. Historical VAST dependency versions retain their original dates.

Source and reproducibility record

The local provenance bundle retains saved-object metadata and checks, source file hashes, output consistency checks, and the read-only extraction scripts. It also preserves the original historical VAST text and historical PDF. The original fit objects and station-level inputs remain in their owning data directory. The report consumes saved metadata and aggregate outputs.

Current-method source code: index workflow and age-composition workflow. Author-documents awaiting access: general methods writeup and terms-of-reference settings.

Appendix I
Assessment Development and Supporting Record

The September 2026 assessment development document (Ianelli et al. 2026), published 3 September, presents the starting model comparisons and exploratory appendices using data through 2024. Corrected through-2024 results are archived with that document; the main assessment uses observations through 2026.

The Plan Team excerpt provides the seven recommendation summaries (Table A1). Its final report citation and any subsequent SSC direction require verification before release.

The source guidelines are Alaska Groundfish Stock Assessment Guidelines, July 2024, in a file named Stock Assessment Guidelines Tier 3.docx. Their publication procedures inform eventual release preparation. The development copy remains local under the user’s release timing.

Early–late fishery sensitivity summaries

Model 26.1.2 evaluates sensitivity to separating the early and late fisheries. Model 26.0 supplies the assessment recommendations.

Model 26.1.2 Early-late fishery split comparison
Quantity
As estimated or specified in 2024 for:
Model 26.1.2 sensitivity for:
2025 2026 2027 2028
Natural mortality (annual rate, ages 3+) 0.300 0.300 0.300 0.300
Tier and sub-tier 3a 3a 3a 3a
Projected total biomass (ages 3+, t) 8,526,000 8,075,000 11,392,000 12,488,000
Projected female spawning biomass (t) 3,118,000 3,342,000 3,223,000 3,432,000
B100% (t) 5,902,000 5,902,000 6,220,000 6,220,000
B40% (t) 2,361,000 2,361,000 2,488,000 2,488,000
B35% (t) 2,066,000 2,066,000 2,177,000 2,177,000
F_OFL (annual rate) 0.513 0.513 0.666 0.666
Maximum F_ABC (annual rate) 0.394 0.394 0.524 0.524
Recommended F_ABC (annual rate) 0.394 0.394 Not selected Not selected
OFL (t) 2,957,000 2,496,000 2,269,000 2,399,000
Maximum ABC (t) 2,417,000 2,036,000 1,855,000 1,958,000
Recommended ABC (t) 2,417,000 2,036,000 Not selected Not selected
Historical source: December 2024 SAFE, Executive Summary, Tier 3 version, p. 4; B40% is printed in section 7.2, p. 35.
2027–2028 projections assume catch of 1,375,000 t in each year, mean 2023–2025 selectivity and fixed biological inputs. Total biomass covers ages 3+ at the start of the year. F_OFL and maximum F_ABC are the fully selected F35% and F40% rates. Biomass and catch are rounded to the nearest 1,000 t.
Model 26.1.2 is a sensitivity analysis. Recruitment is fixed at the fitted 1978–2023 mean; these projections show point estimates. Model 26.0 supplies the assessment recommendation.
Model 26.1.2 Early-late fishery split stock-status summary. The 2025–2026 columns report status for 2025 and 2026; historical determinations are from the 2024 assessment.
Status
As determined in 2024 for:
As determined this year for:
2023 2024 2025 2026
Overfishing No n/a No n/a
Overfished n/a No n/a No
Approaching overfished n/a No n/a No
Historical determinations are from the December 2024 EBS pollock SAFE, Executive Summary, p. 4.
Assessment conclusions are separate from final NMFS determinations. Updated 2025 catch (1,326,215.61 t) is below its 2,957,000-t OFL. For Model 26.1.2, 2026 spawning biomass (3.065 million t) and Alternative 7 biomass in 2028 (3.179 million t) both exceed B35% (2.177 million t), supporting the two 2026 “No” entries. Section 9 describes the status tests. Each two-year column pair reports overfishing for the earlier catch year and stock status for the later assessment year; cells outside those year-specific determinations are marked n/a. NMFS issues the final status determinations.

Assessment archive record

The assessment archive links model source and executable versions, prepared inputs, run controls, saved fits, diagnostics, retrospectives, projections and report products. Source manifests document provenance and access restrictions. Scientific acceptance is documented separately from numerical diagnostics and report preparation.

Annual data-update register

The annual register identifies the input streams, observation years, revisions and weight-at-age treatments used in the assessment (Table I1).

Table I1 Annual Data Additions, Revisions and Weight-at-Age Assumptions
Annual data and weight-at-age register
Data source Year Update or weight-at-age treatment
Fishery catch 2024 Historical catch revision check
Fishery catch 2025 Observed annual update
Fishery catch 2026 Year-to-date plus annual completion forecast
BTS index 2025 Observed annual update
BTS index 2026 Observed annual update
ATS index 2026 Observed annual update
AVO index 2025 Observed annual update
AVO index 2026 Observed annual update
BTS ages 2025 Observed annual update
BTS ages 2026 Observed annual update
ATS ages 2026 Observed annual update
Fishery ages 2024 Observed annual update
Fishery ages 2025 Observed annual update
Fishery weight-at-age 2024 Observed inputs plus forecast 2026
Fishery weight-at-age 2025 Observed inputs plus forecast 2026
Fishery weight-at-age 2026 Forecast schedule
Spawning weight-at-age 2024 A-season schedule correction
Spawning weight-at-age 2025 A-season schedule correction
Spawning weight-at-age 2026 A-season schedule correction
BTS weight-at-age 2025 Survey product with fills
BTS weight-at-age 2026 Survey product with fills
ATS weight-at-age 2025 Assumed carry of 2024 WAA
ATS weight-at-age 2026 Carry or provisional survey product

Note. Annual data additions, revisions and weight-at-age assumptions relative to the 2024 assessment. Listed updates are incorporated in the Model 23.x and 26.x fits. Cumulative input-update fits retain their stated stepwise history.

Appendix J
Contents

Table of Contents

List of Tables

List of Figures