Fishery Biology and Stock Assessment Division

Studies of pelagic ecosystems frequently 
        include surveys of mid-water fauna using large trawl nets. Catches are moved into the ship's laboratory for 
        the demanding tasks of sorting and identification.
Studies of pelagic ecosystems frequently include surveys of mid-water fauna using large trawl nets. Catches are moved into the ship's laboratory for the demanding tasks of sorting and identification.

The Fishery Biology and Stock Assessment Division (FBSAD) conducts fundamental biological and ecological research on fish, sea turtles, and crustaceans caught in federally managed fisheries to enable improved understanding of the mechanisms that influence their distribution and abundance. Life history studies on age and growth, reproduction and fecundity, migration and movement, and mortality are conducted to provide estimates of vital rates for stock assessments and ecosystem-based management. Research is focused on tunas, billfishes, sea turtles, and other pelagic species; bottomfish; and, in the Northwestern Hawaiian Islands, lobster. Attention is also being directed toward coral reef and seamount species.

The research involves field surveys using a variety of sampling gears, laboratory studies of biological specimens, and analysis of data from experiments using conventional and electronic tags. Geochemical techniques are used to investigate trophic levels and population connectivity. New fishing technologies are developed, tested, and promoted internationally to reduce fisheries bycatch and effects of pelagic longline and other fisheries on populations of sea turtles, seabirds, sharks, and other species caught incidentally. The ecology of exploited stocks and effects of stock levels, harvests, bycatch, and conservation measures on the broader ecosystem are explored.

Stock assessments are currently conducted for tunas, billfishes, pelagic sharks, bottomfishes and lobsters. These assessments, along with estimates of the bycatch of sea turtles, seabirds, and marine mammals are provided to support informed decisions by the NOAA Fisheries Pacific Islands Regional Office (PIRO), the Western Pacific Regional Fishery Management Council (WPFMC), and international organizations such as the Western and Central Pacific Fisheries Commission (WCPFC), the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC), and the Inter-American Tropical Tuna Commission (IATTC).

The FBSAD is organized into three programs:

  • The Fishery Biology and Bycatch Program focuses on identifying methods to minimize incidental capture of sea turtles and other bycatch species in pelagic longline and other fisheries, including modifications to fishing gear and bait, and promotes adoption of such methods through outreach and education programs. The program also conducts research on habitats, movements, distribution, and post-release survivorship of fishes, sharks and sea turtles released from pelagic fishing gear. Other research is conducted to model the effects of various factors on the vulnerability of pelagic fishes to capture in longline and other fisheries and to use the results in standardizing catch-per-unit-effort (CPUE) data for pelagic stock assessments. Staff in this program also lead the WPFMC Pelagic Fishery Management Plan Team.
  • The Life History Program conducts basic research on the age, growth, and reproductive strategies of managed fish species and bycatch species. The program also collaborates in studies of coral reef fish community structure and responses of reef fish populations to anthropogenic factors.
  • The Stock Assessment Program conducts population assessments of pelagic species, including yellowfin and bigeye tuna in the western and central Pacific, albacore in the South Pacific, and swordfish, striped marlin, and blue shark in the North Pacific. Assessments are also produced for insular species including bottomfish in the Hawaiian Archipelago, Guam, and Mariana Archipelago and lobster in the Northwestern Hawaiian Islands. Top priority is given to the multispecies complex of bottomfish in the main Hawaiian Islands, which is subject to excessive fishing pressure. The program estimates incidental takes of sea turtles, seabirds, and marine mammals, and the bycatch of fish species (mostly sharks) in the Hawaii longline fishery. The program also develops and implements international collaborative research agreements with foreign scientific institutions and organizations and provides leadership to the WPFMC Hawaiian Archipelago Ecosystem Team and the Western Pacific Stock Assessment Review process (WPSAR).

In addition to directing research activities of the Division, the FBSAD Chief serves as International Science Advisor to the Directors Office, providing critical support and counsel on scientific issues arising with respect to tunas, billfishes, and ecologically associated species in the Pacific. The International Science Advisor is responsible for: providing scientific advice, technical reports, and informed opinion on scientific matters at meetings of the WCPFC, ISC, and other regional fisheries organizations; providing similar scientific support to PIRO, the U.S. State Department, and other members of official U.S. delegations to such meetings; and leading the U.S. delegation at meetings of the WCPFC Scientific Committee. The International Science Advisor also oversees the compilation of official fishery statistics for U.S. fishing fleets harvesting tunas and billfishes in the Pacific Islands Region, and the submission of such statistics to the WCPFC and other regional field offices.

FBSAD staff provide expertise, advice and leadership within scientific working groups of international fishery organizations including WCPFC and ISC, and in support of multilateral efforts to establish a regional fisheries management organization for the northwest Pacific.

FBSAD staff members also help the Directors Office in overseeing NOAA Grants to the Oceanic Institute, advise the State of Hawaii on matters related to introduced and invasive species, and organize and maintain the PIFSC schedule of research cruises on the NOAA Ship Oscar Elton Sette.

FBSAD has a staff of 32 people including 21 federal employees and 11 employees of JIMAR. Staff salaries and benefits made up the largest share of expenditures in FY 2009.

Fisheries Monitoring and Socioeconomics Division-FY 2009
  $ %
Salaries and benefits 2,418,209 58.6
Grants 288,546 7.0
Contracts 849,465 20.6
Travel, transportation, charters, printing, supplies, equipment 567,355 13.8
Total $4,123,575  
FMSD Personnel
Federal 21
Total 32

Key 2009 Accomplishments

  • Completed research on the effects of a gear depth modification in the American Samoa-based longline fishery for use by the WPFMC in developing turtle bycatch mitigation measures.
  • Estimated incidental takes of sea turtles, seabirds, and marine mammals in the 2008 Hawaii longline fishery.
  • Completed a paper on using productivity and susceptibility indices to determine the vulnerability of managed fish stocks.
  • Provided science-based advocacy for sea turtle bycatch reduction methodologies at the 5th Annual Meeting of the WCPFC resulting in the adoption of a Conservation and Management Measure requiring the use of circle hooks or fish bait in shallow-set longline fishing.
  • Cochaired and lead the U.S. Delegation to the annual meeting of the WCPFC Scientific Committee; reports are posted on the WCPFC Web site at:
  • Completed U.S. Annual Reports and data submissions to the WCPFC and ISC.
  • Convened and chaired meetings of the ISC Billfish Working Group. Meeting reports are posted on the ISC Web site at:
  • Served as lead of the U.S. Science Delegation to the 4th Scientific Working Group Meeting of the Inter-Governmental Meeting on Management of High Seas Bottom Fisheries in the north western Pacific Ocean, providing expertise on biology and fisheries of the Emperor-Northern Hawaiian Ridge seamounts.
  • Provided U.S. longline catch forecast products to PIRO for guiding compliance with bigeye tuna catch limits set by the WCPFC and IATTC in the western and eastern Pacific Oceans, respectively.
  • Collaborated in updating stock assessments of bigeye and yellowfin tuna in the western and central Pacific, and albacore in the South Pacific.
  • Contributed scientific inputs to the WCPFC, ISC, and WPFMC on a range of topics including status of stocks, CPUE standardization, and bycatch mitigation.
  • Published North Pacific blue shark stock assessment.
  • Completed and published a collaborative stock assessment of North Pacific swordfish.
  • Completed an updated bottomfish stock assessment and Total Allowable Catch risk analysis for MHI bottomfish and provided results to the WPFMC and other stakeholders for their use in setting catch limits.
  • Completed a scientific peer review of the bottomfish stock assessment through WPSAR.
  • Chaired a workshop on deep slope bottomfish science ecosystem and monitoring.
  • Collaborated in a publication on the reproductive ecology and scientific inference of "steepness," a fundamental metric of population dynamics and strategic fisheries management.
  • Published a study on methods for age determination of billfishes using fin spine cross sections.
  • Discovered a cryptic, second North Pacific species of moonfish (Lampris), a large pelagic predator, based on genetic and morphometric analyses.
  • Developed cooperative research agreements with Japan's National Research Institute of Far Seas Fisheries for billfish research, and with Shanghai Ocean University on a suite of biological, ecological, and economic research topics.

Challenges, Problems, and Limitations

Biological specimens, like this ehu, provide 
        information needed to improve stock assessments and scientific advice for fishery managers.
Biological specimens, like this ehu, provide information needed to improve stock assessments and scientific advice for fishery managers.

Although the Division Chief serves as International Science Advisor for the U.S. delegation to WCPFC and FBSAD staff members contribute significantly to scientific work in support of the WCPFC, ISC, and other regional international fisheries agreements, PIFSC has not received funding to provide such scientific support. The budget for fish bycatch research and for other fish and ecosystem research is very limited. Core fish stock assessment tasks are substantially funded, but mandates to assess additional species and meet new requirements of the Magnuson-Stevens Fishery Conservation and Management Act, particularly establishment of annual catch limits for all fisheries, are underfunded.

Within the Center, challenges remain with developing and coordinating integrated research programs needed to support ecosystem approaches to management of living marine resources. One of the challenges for FBSAD scientists is to improve stock assessments with a focus through greater use of oceanographic data products developed by EOD.

Among other challenges, FBSAD has been asked to help assess coral reef fisheries and provide scientific advice to the State of Hawaii on management of fisheries in the main Hawaiian Islands through closed areas and other means. Information is often lacking to adequately address these issues, which have traditionally been outside federal jurisdiction.

Future Focus and Direction

Testing of improved fishing gear to reduce longline bycatch will continue, in collaboration with other nations, with a focus on sea turtles and sharks. Recommendations for international fisheries conservation measures on bycatch, and methods to reduce incidental catches of billfishes in Pacific-wide longline fisheries will be actively promoted. Bycatch work will include completion of a new National Bycatch Report with coverage of all fish species and protected species.

New research will be focused on bottomfish life history, distribution, and stock dynamics throughout the US. Pacific Islands, using cooperative research funding, other new funding, and NOAA fisheries research vessels. The feasibility of conducting fishery-independent bottomfish surveys in the region will be explored, and a bottomfish tagging study will be undertaken to assess movements between banks. The Life History Program will develop new capabilities using more advanced techniques, such as lead-radium and carbon-14 age determination, to estimate age and growth of long-lived fishes such as the deep slope bottomfishes. Work will continue on standardizing bottomfish CPUE data to account for previous changes in the fisheries, so that trends in stock abundance over time can be more accurately described and assessments can be improved.

A comprehensive Pacific Islands Fisheries Science Center Plan for Pacific Highly Migratory Species Science will be completed in FY 2010. Review and improvement of stock assessments for tunas, billfishes, and sharks will continue under the auspices of the WCPFC and ISC. Significant effort will be devoted to standardizing and documenting methods of fishery data processing and reporting to meet increasing demands of international agreements for information and advice. Methods for forecasting fish catches using additional sources of near-real time information and more comprehensive modeling and risk assessment will be developed to improve the advice available to managers attempting to comply with annual catch limits.

Review of Billfish Ageing Using Fin Spines Indicates Need to Develop Best Practices

A key requirement of age-structured fish stock assessment is an accurate method to determine the ages of fish in the catch. In billfishes, ageing relies primarily on the analysis of fin spines collected from sampled fish. Identification of temporal periodicity in fin spine growth increments has enabled scientists to judge the relative age of billfish by counting the increments in cross sections of spines. Ageing procedures can be applied to samples of fish to estimate the age-composition of the catch. Age estimates of individual specimens can be used with measurements of body length to construct billfish growth curves. However, researchers in different parts of the world, working independently of each other, have adopted different approaches to fin spine ageing, adding to uncertainty in billfish stock assessments and regional comparisons of stock dynamics.

To resolve these differences, a team of billfish experts from PIFSC, University of Miami, and Australia's Charles Sturt University critically reviewed fin spine techniques used by billfish biologists to age the fish, with a focus on age determination in striped marlin (Kajikia audax) in the Pacific Ocean and white marlin (Kajikia albida) in the Atlantic. The group systematically reviewed the methods used in their research organizations to collect, prepare, and analyze fin spines from these marlin species. They examined an array of topics including fin spine selection; preparation and sectioning of spines; characteristics of annual increments; identification of false increments; measurement of fin spine cross sections; spine vascularization; classification of increments at the edge of the spine section (indicative of most recent growth); assignment of age; and validation of age estimates. Each topic was explored in detail, and strengths and weaknesses of alternative methods were assessed.

Because billfishes in all oceans are highly migratory, they occur in the fisheries of many nations. Differences between nations in the methods used to age billfish may lead to discrepancies in age composition data used to assess the billfish stocks. Moreover, inconsistencies in ageing methods can make it difficult to determine whether interregional variations in growth estimates are real or just a result of different methodology; resolving such discrepancies is important for accurate stock assessment.

Based on their study, the reviewers recommended that a general framework or code of practice be developed to govern age estimation of closely allied billfish species, such as the striped and white marlins. Adoption of common, standardized best practices would enable regional comparisons of growth results and more reliable stock assessment of shared billfish resources.

The collaborative research was published in the peer-reviewed journal Aquatic Living Resources.

Reference: Kopf, R. K., K. Drew, and R. L. Humphreys. 2009. Age estimation of billfishes (Kajikia spp.) using fin spine cross-sections: the need for an international code of practice. Aquat. Living. Resourc. 22. [].

Growth increments 
            in striped marlin fin spines can be studied in images of spine cross sections. Increments can be 
            identified, counted, and measured in a normal view (a), inverted view (b), embossed view (c) or digitized 
            view (d).
Growth increments in striped marlin fin spines can be studied in images of spine cross sections. Increments can be identified, counted, and measured in a normal view (a), inverted view (b), embossed view (c) or digitized view (d).
Last updated July 26 2011