NOAA logo JFM 2000 Quarterly Rpt. sidebar

Resource Ecology &
Fisheries Management

(Quarterly Report for Jan-Feb-Mar 2000)

Resource Ecology and Ecosystems Modeling Program

Laboratory analysis was performed on 1,062 groundfish stomachs from the eastern Bering Sea and 508 from the Gulf of Alaska.  No observers returned with stomach samples during the quarter.

Eastern and Western Bering Sea Comparisons
We are collaborating with Russian scientists at the Pacific Fisheries Research Center (TINRO) in Vladivostok, Russia, in the  development of a mass-balance model of the western Bering Sea for the 1980s period.  A preliminary model has just been completed and will be compared with the eastern Bering Sea mass-balance model that already exists for the same period.

By Pat Livingston.

Age and Growth Program

Estimated production figures for 1 January to 31 March 2000 were 4,627 walleye pollock, 161 sablefish, 420 Atka mackerel, 1,805 Pacific whiting, 198 northern rockfish, and 498 light dusky rockfish.  Total production figures were 7,709 with 952 test ages, and 53 examined and determined to be unageable.

At the request of the Stock Assessment Program, the Groundfish Observer Program has changed the sampling of fisheries to small random samples collected by all at-sea observers.  For 1999 samples, the Age and Growth Program spent time relabeling and restoring otolith vials into Styrofoam boxes.  This task, required before age determination, has been completed for the 1999 samples and will be carried out by the Observer Program in the future.  The change in sampling method should allow the collection and age determination of a wider variety of species than in the past.

By Dan Kimura.

U.S. Groundfish Observer Program

During the first quarter of 2000, 284 observers were trained, briefed, and equipped for deployment to fishing and processing vessels and shoreside plants in the Gulf of Alaska, Bering Sea, and Aleutian Islands region.  They sampled aboard 312 fishing and processing vessels and at 26 shoreside processing plants.  These observers were trained or briefed in various locations.  The University of Alaska Anchorage (UAA) Observer Training Center  trained 35 first-time observers, and another 99 observers with prior experience were briefed at this site.  The Alaska Fisheries Science Center (AFSC) Observer Program in Seattle briefed 136 observers.  At the Observer Program’s field office in Dutch Harbor, 3 more observers were briefed,and 11 were excused from briefing because they had just completed a cruise successfully and were returning immediately to the field.  The first quarter 2000 observer workforce thus comprised 12% new observers and 88% experienced observers.

The Observer Program conducted a total of 93 debriefings during the first quarter of 2000.  Three debriefings were held in Kodiak, 4 in Dutch Harbor, 18 in Anchorage, and 65 were held in Seattle.

CDQ and AFA Fisheries

Implementation of an expanded Community Development Quota (CDQ) Program and implementation of provisions of the recently enacted American Fisheries Act (AFA) continued during 2000.  The CDQ program was developed for the purpose of allocating fishery resources to eligible western Alaska communities to provide the means for starting or supporting commercial fishery activities that would result in ongoing, regionally-based, commercial fishery or related businesses.  The CDQ Program  was initiated in 1992 with pollock and expanded to include fixed-gear halibut and sablefish in 1995.  In 1998, it was further expanded to include multiple species of groundfish and crab (MSCDQ).  In 1999, NMFS became responsible for monitoring the groundfish (including pollock and sablefish) and halibut CDQs and the state of Alaska for monitoring the crab CDQs.  This division of responsibility continues into 2000.

The AFA, enacted by Congress in late 1998, made changes to the pollock fishery in the Bering Sea and Aleutian Islands region.  These changes included reallocation of fish among industry segments, provided for the formation of fishing cooperatives, and increased observer coverage levels on some components of the fleet.  The offshore component of the fleet has organized a fishing cooperative this year and has been receiving increased, mandatory observer coverage.  More recently, the Observer Program has been involved in implementation of aspects of the AFA related to shoreside processors.  The shoreside component has proven to be more complex than offshore and will involve possible NMFS regulatory actions and a changing role for the observer.

The MSCDQ and AFA catch accounting for offshore processors is based entirely on data collected by observers and, unlike the open access fisheries where observer data is used to manage a fleet- wide quota, industry participants in the MSCDQ and AFA fisheries require individual accounting of fish harvested in each haul or set.  This change in expectations placed on observers, their data, and the Observer Program in general has required much Observer Program staff effort in the development of special selection criteria and training requirements for observers, development of new sampling strategies and regulations to enhance the observer’s working environment, and changes to the data collection and data management software systems.

Observer Program Review

An extensive, independent review of the Observer Program began in late 1999.  The review is being carried out by Marine Resources Assessment Group (MRAG) Americas, Inc.  MRAG is an independent consulting firm which provides professional advice and services for the management of marine fisheries throughout the world.  The purpose of this review is to provide recommendations for changes in Program operations and organization which might improve the Program’s ability to meet its mission and goals.  Their final report is due 30 April 2000.  MRAG is also under contract to design a multispecies, biological sampling protocol and statistically-based method of catch estimation for use by observers.  The completion of this second project is expected in November 2001.

In addition to the MRAG review, the Observer Program is also being reexamined this year, along with all other NMFS observer programs, through the annual NMFS management control review  process.  The newly established National Observer Program Advisory Team (NOPAT) will be actively involved in this endeavor.  NOPAT is made up of representatives from all NMFS regional offices, fisheries science centers, and observer programs and is coordinated through the National Observer Program office of NMFS.

Cadre  Takes Shape

Office space is being constructed in Anchorage for 10 new Observer Program employees.  These new employees and the existing two positions in Anchorage will make up the Observer Program “Cadre.”  The cadre will be an inherently flexible unit of employees that can be deployed as needed to ports throughout Alaska.  They will increase the Observer Program’s presence in the field and allow for more front-line communication between NMFS, observers, and the fishing industry.  The new offices are scheduled to be ready for occupancy sometime in May of this year with the first of the cadre prepared for deployment in August 2000.

By Bob Maier.

Socioeconomic Assessments Program

Cost, Earnings, and Employment Survey

Cost, Earnings, and Employment surveys were delivered to all participants in the Bering Sea-Aleutian Islands (BSAI) pollock fishery in mid-January.  The participants include owners of catcher vessels, catcher processors, shoreside processing plants, and motherships.  To date, the response rate to the voluntary survey has been low.  Center economists have been in contact with survey recipients and relevant industry organizations to encourage more responses.  It is hoped that the passing of the 1999 tax season and these discussions will produce more responses.

Preliminary Capacity Report
Typically, there is said to be excess fishing capacity when the existing fleet is capable of catching more than the optimum yield.  Excess fishing capacity often results in significant economic losses even when it does not result in overexploitation of fish stocks.  Excess fishing capacity has been identified nationally and internationally as a major fishery management problem.  Members of the Socioeconomic Program conducted a qualitative assessment of excess fishing capacity for Federally regulated fisheries off Alaska as part of a NMFS initiative to assess and address the problem of excess fishing capacity.  The qualitative assessment will be followed by  a quantitative assessment that will be completed by the end of August 2000.

Qualitative assessments were preformed for five fisheries: Gulf of Alaska (GOA) groundfish, Bering Sea-Aleutian Islands (BSAI) groundfish, Alaska king and Tanner crabs, Alaska weathervane scallops, and the Pacific halibut and sablefish IFQ (individual fishing quota) fisheries.  The qualitative assessment provided direct and indirect evidence to address the following four questions:

1) Are catches regularly exceeding the levels recommended by fishery managers?

2) Could the current fleet catch more than the recommended levels if not constrained by regulations such as season length or quotas?

3) Could a smaller fleet take the recommended catch levels at lower cost than the present fleet?

4) Are there incentives in place that are likely to lead to increases or the maintenance of excess capacity?

Because relatively good data exist on catches in these fisheries, answering the first question is simple.  In general, harvests in excess of recommended levels are not a problem in Alaska fisheries.  The answer to questions two and three is probably “yes” for most fisheries off Alaska, though there are important differences in the nature and magnitude of the adverse effects of excess capacity among these fisheries.   The answer to the fourth question is “yes,” except for the sablefish and halibut IFQ fisheries and the BSAI pollock fishery.  As long as there are no incentives in place to fuel further investments in capacity and catches are controlled, it may be unnecessary or even counterproductive to reduce capacity directly. On the other hand, if there is reason to fear the excess capacity will spill over into other fisheries, it may be necessary to reduce capacity directly.

The general, qualitative assessments for each fishery follow. Gulf of Alaska Groundfish:Excess Capacity Exists. Bering Sea and Aleutian Islands Groundfish: Excess Capacity Exists. Halibut and Sablefish:Excess Capacity Exists. Alaska King and Tanner Crab Fisheries: Excess Capacity Exists. Alaska Weathervane Scallop Fishery: Excess Capacity Exists.

By Joe Terry.

Guidelines for the Economic Analysis of Fishery Management Action

NMFS has placed a high priority on preparing a document that would provide guidance on understanding and meeting the procedural and analytical requirements of Executive Order 12866 and the Regulatory Flexibility Act for regulatory actions for Federally-managed fisheries.  AFSC economists contributed substantially to the preparation of the latest draft of the guidelines.

NMFS Economics and Social Science Conference

Center economists participated in the NMFS Economics and Social Science Conference in La Jolla in February.  Dan Holland and Todd Lee presented “Cost-Earnings Survey Design Issues."  The presentation covered many issues related to using accounting data for economic analysis.  Holland presented “Using Random Utility Models in Commercial Fishing."  This paper addresses how variations in catch rates and cost, and individuals’ past behavior can be used to model fishery and location choice at the individual level.  The paper also discussed how these individual level models can be used to predict the distribution of effort at the aggregate level.

Lee presented “The effect of fishery attributes on participation rate: A conjoint analysis with applicability to IMPLAN.”  This paper used stated preference data by recreational anglers to predict participation rates as a function of fishery characteristics.  Results from the behavior model were then linked to a regional economic impact model.

By Joe Terry.

Status Of Stocks and Multispecies Assessment Program

AFSC-ADF&G Joint Research Meeting

The AFSC and the Alaska Department of Fish and Game held a joint groundfish research meeting 28-29 February 2000 at the Center’s Sand Point facilities in Seattle.  This was the second annual meeting, and 32 groundfish fisheries scientists attended.  The purpose of the meeting was to brief scientists from both institutions on ongoing or planned research programs and to foster cooperation between the two agencies.

Discussions focused on the groundfish survey effort planned for the year 2000.  Surveys will include trawl surveys in the EBS, AI and GOA, fishery oceanographic surveys for walleye pollock, adaptive sampling trawl surveys for rockfish, sablefish longline surveys and EBS, AI and GOA echo integration-trawl surveys for pollock.  Research activities were also discussed, such as effects of fishing studies using acoustics and trawl catchability-performance research, life history-biological research, and essential fish habitat research.  Assessment scientists described their plans for utilizing survey data in groundfish stock assessments for the year 2000.  The meeting provided a forum for discussion of cooperative research plans.

By Anne Hollowed.

Sixth National Stock Assessment Workshop

The sixth NMFS National Stock Assessment Workshop was held in Seattle during 28-30 March 2000.  The theme of the workshop was “Incorporating ecosystem considerations into stock assessments and management advice.”  Approximately 28 AFSC scientists joined colleagues from other fisheries science centers and headquarters.  A total of 45 papers and posters were presented during four sessions focusing on ecosystem properties, biological and technological interactions, short- and long-term climate effects, and secondary effects of fishing.

The following 12 papers and posters were contributed by AFSC scientists:

  1. Ecosystem considerations in fisheries management:  Linking ecosystem management goals with ecosystem research,” by Pat Livingston.

  2. “Incorporating spatial dynamics of fish and fishermen in models of marine protected areas on Georges Bank,” by Dan Holland.

  3. “Measures of overfishing based on MSY,” by Charles Fowler

  4. “Evaluation of single-species versus multi-species models in the context of managing for maximum sustainable yield,” by Grant Thompson.

  5. “The bycatch and mixed species yield-per-recruit of flatfish fisheries on the Eastern Bering Sea shelf,” by Paul Spencer and Tom Wilderbuer.

  6. “Use of surficial sediment information and species assemblage analysis for improving trawl survey stratification and abundance estimation,” by Mark Zimmermann.

  7. “Multispecies perspectives on the Bering Sea groundfish fishery management regime,” by Jesus Jurado-Molina and Pat Livingston  (.pdf, 730 KB).

  8. “The influence of spatial dynamics on predation mortality of Bering Sea walleye pollock,” by Pat Livingston, Paul Spencer, Troy Buckley, Angie Greig, and Doug Smith.

  9. “Carrying capacity of apex predators and the frequency and cadence of physical forcing in marine food webs,” by Kerim Aydin.

  10. “Climate forcing effects on trophically-linked groundfish populations: implications for fisheries management,” by Jesus Jurado-Molina and Pat Livingston.

  11. “Steller sea lion-induced changes in the management of pollock and Atka mackerel fisheries in the North Pacific, 1998-2000,” by Lowell Fritz.

  12. “Straying from the Eco path (a critique/demo of the ECOPATH/ECOSIM/ECOSPACE Programs),” by Kerim Aydin and Chris Boggs.

In addition to presentation of papers and posters, the workshop afforded the opportunity for NMFS scientists to share information and develop recommendations in discussion groups corresponding to the topics of the workshop sessions.  Two of the four discussion groups were chaired by REFM scientists Anne Hollowed and Pat Livingston.  The workshop concluded with a plenary session in which participants reviewed reports of the discussion groups and developed additional recommendations for future research.

The proceedings of the workshop, consisting of abstracts, discussion group reports, and plenary session recommendations will appear in the near future as a NOAA Technical Memorandum.

By Grant Thompson.

Walleye Pollock Study

Study was completed on the spatial and temporal differences in growth and productivity of walleye pollock in the Eastern Bering Sea.  Survey and commercial fishery databases were used to investigate spatial and temporal differences in growth and productivity of walleye pollock in the eastern Bering Sea.  In addition, age-3 recruitment was correlated with regional time series of oceanographic and atmospheric variables, adult pollock numbers, and commercial catch data (assumed to be an index of incidental catch/mortality of prerecruit pollock).

Cluster analyses on summer bottom trawl length data suggested that pollock group in distinct clusters based on size.  The northwest and southwest (outer strata) contained two modes of medium-sized fish, while the northeast and southeast (inner strata) contained one mode each of small and large fish.  These strata, defined by cluster analysis, roughly corresponded to distinct oceanographic domains of the southeastern Bering Sea determined by the 7-year PROBES study conducted by C. P. McRoy et al. in 1986.

Age-length keys were compared statistically using log-linear analysis to determine if significant differences existed in age distributions at length between the strata defined by cluster analysis.  The age-length keys were significantly different from 1982 to 1996, but not in 1997 and 1998.  Further, the use of a single, global age-length key, instead of local keys, had a significant impact on the estimated pollock population-at-age and mean length-at-age.

Age composition results showed that the pollock population is spatially stratified by age.  The majority of age-1 fish reside demersally over the northern strata.  By age 2, these fish move upward in the water column and become part of the pelagic component of the stock.  The pelagic component of the stock (mainly fish age 2 to 5) becomes progressively more demersal over time.  The inner strata show large sequential increases in demersal numbers-at-age for older age groups.

Nonlinear regression analysis showed statistically significant differences in growth between the four cluster-defined strata of the eastern Bering Sea.  Within a horizontal cline (west to east), fish from the outer shelf were bigger at age than fish from the inner shelf through age 4.  From age 7 and older, fish from the inner shelf were bigger at age than fish from the outer shelf.  Within a vertical cline (north to south), fish from the south were slightly larger at age than fish from the north.  The age composition and mean length-at-age results suggest that a seasonal migration of adult pollock onto the inner shelf is taking place.

The eastern Bering Sea pollock population and biomass have shown decreasing trends over the last 15 years.  Potential reasons for this decline were identified through cross-correlation analysis, which identified factors that were significantly associated with recruitment success.  The two most important environmental variables were ocean bottom temperature and wind stress.  Above average water temperature at age 1 and wind stress directing prerecruit pollock toward the northern inner shelf were associated with above average future age-3 recruitment.

Correlation analysis showed that large numbers of old, adult pollock were associated with below average future age-3 recruitment.  This negative association suggests that there is a density-dependent relationship between the number of spawners and future recruits.

Commercial pollock catch in the southwest stratum when prerecruits are 2 years old is negatively associated with the number of age 3 recruits the following year.  Because the quantity of fish caught in the southwest stratum has significantly increased over the last 5 years, spatial trends in juvenile bycatch rates should be examined further.

For more information about this study, contact Anne Hollowed at or 206-526-4223.

By Chris Shuck.