RESOURCE ECOLOGY & FISHERIES MANAGEMENT (REFM) DIVISION

RESOURCE ECOLOGY AND ECOSYSTEM MODELING PROGRAM:

Fish Stomach Collection and Laboratory Analysis

Laboratory analysis was performed on 1,796 groundfish stomachs from the eastern Bering Sea and 743 from the Gulf of Alaska. A total of 5,610 stomachs were collected from the Bering Sea and 3,397 from the Gulf of Alaska from research vessels.

By Troy Buckley.


PICES Ecosystem Status Report Workshop

Pat Livingston, Bern Megrey, and Franz Mueter attended the North Pacific Marine Science Organization (PICES) international workshop in Victoria, British Columbia, 25-27 August. The workshop was organized as part of an effort to develop a North Pacific Ecosystem Status Report. Pat Livingston is overseeing the Bering Sea chapter of the report and Bern Megrey and Franz Mueter are providing the Gulf of Alaska chapter.

Participants from both sides of the North Pacific gathered to present information about the status of various ecosystems around the North Pacific and to discuss ways to standardize the content and structure of the report. The main purposes of the workshop were to:

• review the regional chapter drafts of the North Pacific Ecosystem Status Report (NPESR)
  
• develop a synthesis/summary of ecosystem status for the North Pacific Ocean based on these regional reviews
  
• discuss use of this information to develop “Marine life in the North Pacific: the known, unknown, and unknowable” for the Census of Marine Life.

By Pat Livingston.


Ecosystem Assessment Strategy

A draft strategy for providing an ecosystem assessment of the Bering Sea-Aleutian Islands and Gulf of Alaska regions was developed by scientists in the Resource Ecology and Ecosystem Modeling Program. The strategy, modeled after the framework used for ecosystem impact assessment in the draft Programmatic Groundfish Fisheries EIS (PSEIS), provides a systematic way of evaluating ecosystem effects of fishing with respect to predator/prey relationships, ecosystem energy flow, and various measures of diversity. The strategy is intended to complete the intent of the Ecosystem Considerations section that has become a regular accompaniment to the North Pacific Fishery Management Council’s (NPFMC) Stock Assessment and Fishery Evaluation (SAFE) documents.

While the Ecosystem Considerations section provides historical status and trend information for a variety of ecosystem components, the Ecosystem Assessment is intended to provide advice on possible future trends in the ecosystem, using total allowable catch (TAC) scenarios of the annual TAC-setting Environmental Assessment. The Ecosystem Assessment will allow us to fulfill TAC Environmental Assessment requirements to annually assess environmental consequences of TACs on the ecosystem. It also helps meet the guidelines of National Standard 2- scientific information in the Magnuson-Stevens Act, that specify that the SAFE report should contain information on past, present, and possible future conditions of the stocks, marine ecosystems, and fisheries being managed. Lastly, the assessment will provide guidance on possible aggregate effects of fishing that are not captured under single species assessments.

Multispecies and ecosystem models are proposed as tools to provide advice on possible future trends in various ecosystem indicators. Three models are envisioned for future use in this assessment. The first is a multispecies bycatch model employed in the PSEIS, which provides single-species population projections for groundfish targets along with prohibited species bycatch and optimal yield constraints presently operating in the Bering Sea-Aleutian Island (BSAI) and Gulf of Alaska (GOA) groundfish fisheries to provide realistic future fishing trajectories on target species and indicators of the types and amounts of bycatch. Multispecies virtual population analysis and forecasting models provide an age-structured predator/prey assessment on target groundfish species and ecosystem mass balance and biomass dynamics models provide a more holistic view of possible future trends in ecosystem components. Finally, climate is an important aspect of our prediction of the future state of ecosystems. Work is ongoing among NOAA components to develop more real-time assessment of changing climate states and responses of organisms to those changes. These are incorporated into our ecosystem considerations section of the SAFE and will require discussion about how to incorporate climate into our assessment of possible future climate effects on North Pacific ecosystems.

By Pat Livingston.


Climate and Food Web Models Workshop

A 3-day workshop on the detection of climate anomalies in marine food web models was hosted by the Department of Fisheries and Oceans (DFO) Canada, 16-18 September, in Nanaimo, British Columbia. Participants discussed methodology for comparing modeling efforts from North Pacific regions from Northern California through British Columbia and Alaska, with the purpose of using these models to detect Pacific-wide climate signatures in fish production patterns. This project will be pursued through at least one follow-up meeting in Spring 2004 and may additionally be expanded to include food web research from the western Pacific through the participation of Asian members of PICES.

By Kerim Aydin.

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AFSC Quarterly
Research Reports
July-Sept 2003