Research
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Current Research
Our current research topics include:
International Cooperative High Seas Salmon Research (NPAFC)
The current goal of our international cooperative high seas salmon research is to advance scientific understanding of the effects of climate and ocean conditions on marine survival of Pacific salmon and steelhead. In 2005, we participated in the development of a new 5-year (2006-2010) NPAFC Science Plan. Two overarching hypotheses emerged from the results of scientific research under previous NPAFC science plans, as well as from research by other organizations and independent scientists: (1) salmon play an important role in North Pacific marine ecosystems, and (2) there is a close relation between climate and climate change and subsequent changes in marine productivity and survival of salmon in the ocean.
Two broad scientific questions relevant to the program goals of NPAFC were identified:
- What are the current status and trends in marine production of anadromous stocks; and how are these trends related to population structure (spatial and temporal) and diversity of salmon in marine ecosystems of the North Pacific?
- How will climate and climate change affect salmon, ecologically related species, and their North Pacific marine ecosystems?
Over the past decade, significant annual variation in the marine production of Asian and North American salmon appears to be linked to climate change. There is a strong need for new international cooperative research that provides better scientific information on the status and trends in marine production of salmon, identifies the roles of salmon in North Pacific marine ecosystems, and examines the extent to which salmon, since they return to coastal regions, can be used as indicators of conditions in North Pacific marine ecosystems.
Variation in the time, frequency, and amplitude of climate events that affect the ocean production of marine fish seems to be increasing. This has led many experts to conclude that precision monitoring of abundance and biomass in the ocean may be the only reliable method for predicting changes in production of salmon. That each species of salmon follows a life history strategy in the ocean is probable. Cooperative research that identifies the common mechanisms will improve regional forecasting. In addition, the conceptual framework for the management of fish populations has expanded from relatively simple assessments of abundance and productivity to broader needs for information on population structure (spatial and temporal) and diversity.
International Cooperative research under the 2006-2010 NPAFC Science Plan is focused on one research theme:
Status and Trends of Production of Anadromous Stocks in Ocean Ecosystems
The influence of regional and local environmental stressors on the status of different salmon species and stocks at initial and subsequent life history stages is varied. These stressors may affect the quantity and biomass of juvenile salmon migrating to the sea, immature and maturing salmon migrating in the open ocean, and adult salmon returning to coastal and freshwater fisheries. Obtaining reliable abundance estimates is essential to understanding survival at each marine life history stage. For sustainable conservation of salmon, better scientific information is needed on the effects of climate and climate change on salmon, ecologically related species, and their North Pacific marine ecosystems.
Cooperative research activities will attempt to clarify the present status and trends in production of salmon, to determine important stressors and stressor regimes that affect population structure and diversity, to evaluate subsequent effects of these mechanisms on the viability and performance of salmon at critical marine life-history stages, and to evaluate effects of climate and climate changes on marine production of salmon.
Cooperative high-seas salmon research under the broad theme of “Status and Trends of Production of Anadromous Stocks in Ocean Ecosystems” is focused on three components:
- Status and Trends of Juvenile Salmon in Ocean Ecosystems
In at least some species of anadromous stocks (e.g. pink and chum salmon), variation in adult returns may depend more on marine survival than on reproductive efficiency during the freshwater period. A common hypothesis is that the initial period of after migration to sea is the most critical phase with respect to ocean survival of salmon. Recent cooperative and national research on juvenile salmon suggests considerable interannual variation in abundance, growth, and survival rates of juvenile salmon in the ocean. These variations may be related to climate-induced changes in habitat environments that operate at regional and local scales. To a greater or lesser extent, these processes are monitored annually in marine survey areas along the coasts of Asia and North America. A better understanding of these processes is needed for sustainable conservation and management of salmon.
- Status and Trends of Anadromous Stocks in the Bering Sea Ecosystem (BASIS)
The centerpiece of NPAFC’s coordinated program of marine ecosystem research to date is the Bering-Aleutian Salmon International Survey (BASIS). In 2001-2002, we assisted in the development and implementation of BASIS. Under the 2001-2005 Science Plan, BASIS research progressed and evolved to more complex research issues, and has become an integral part of ecosystem research planned by other international, national, and regional conservation, management, and research organizations, e.g., the North Pacific Marine Sciences Organization (PICES), the U.S. National Marine Fisheries Service (Alaska Fisheries Science Center, Auke Bay Laboratory), and the Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative).
In the face of global climate change, the Bering Sea may become the most important marine ecosystem for production of Asian and North American salmon. The results of cooperative BASIS ecosystem monitoring research in 2002-2004 indicated a very high density of Asian and North American salmon in the Bering Sea from summer to late fall. BASIS process studies have demonstrated the important influences that various physical and biological stressors and stressor regimes may have on production of anadromous stocks and ecologically related species in the Bering Sea ecosystem. While this recent research confirms the high productivity of the Bering Sea, carrying capacity, growth, and production of salmon has shown a high degree of variation. These results confirm the necessity of continuing cooperative research in the Bering Sea to clarify the mechanisms of biological response of salmon to climate and climate change.
- Status and Trends of Anadromous Stocks in the Western Subarctic Gyre and Gulf of Alaska Ecosystems
Salmon play a very important role in the Western Subarctic Gyre and Gulf of Alaska ecosystems. Immature and maturing salmon originating from Asia and North America intermingle in both of these ecosystems. Recent research vessel surveys by Canada, Japan, Russia, and the USA have collected a considerable amount of new data on anadromous stocks, ecologically related species, and environmental conditions in the Western Subarctic Gyre and Gulf of Alaska ecosystems. In particular, three species – pink, chum, and sockeye salmon – occur in high abundance in Western Subarctic Gyre and Gulf of Alaska ecosystems during all seasons. Salmon consume a substantial quantity and biomass of prey organisms in these ecosystems, and play an important role as a higher trophic level predator. Changes marine tropic relations in these ecosystems influence the productivity of salmon populations returning to different reproduction regions in Asia and North America.
Both ecosystems provide the major wintering habitats for various salmon stocks. While previous research has identified this as a critical period that defines the biological characteristics and biomass of salmon, open ocean field research and monitoring programs have typically been carried out only during the late spring to early fall period. Better information on the status and trends in production and condition of Pacific salmon during the late fall to early spring period is needed for sustainable conservation and management of salmon resources.
Knowledge of variation in the characteristics of marine production in the Western Subarctic Gyre and Gulf of Alaska ecosystems is needed for sustainable conservation of Pacific salmon and steelhead resources in Asia and North America. In addition, more accurate forecasts of adult salmon returns will benefit salmon industries around the Pacific Rim.
U.S. GLOBEC Research
U.S. GLOBEC (GLOBal ocean ECosystems dynamics) is a research program organized by oceanographers and fisheries scientists to address the question of how global climate change may affect the abundance and production of animals in the sea.
Our current U.S. GLOBEC research (Principal Investigators: D. Beauchamp, K. Myers) is part of the Northeast Pacific (NEP) program. The goal of this program is to understand the effects of climate variability and climate change on the distribution, abundance and production of marine animals (including commercially important living marine resources) in the eastern North Pacific. To embody this understanding in diagnostic and prognostic ecosystem models, capable of capturing the ecosystem response to major climatic fluctuations. The NEP research is focused on two oceanic regions: the California Current System and the Coastal Gulf of Alaska (CGOA).
Our research addresses Goal #4 of the GLOBEC CGOA Program: “to determine the extent to which high and variable mortality of juvenile pink salmon in the coastal region of the Northern Gulf of Alaska is responsible for large interannual variation in adult salmon populations.” We are exploring Core Hypothesis #3 in the GLOBEC NEP Implementation Plan: “ocean survival of salmon is primarily determined by survival of the juveniles in coastal regions, and is affected by interannual and interdecadal changes in physical forcing and by changes in ecosystem food web dynamics” (U.S. GLOBEC 1996).
Project Summary
Inter-annual differences in stage-specific survival and growth of pink salmon will be examined in relation to monthly differences in spatial distribution and spatial-temporal patterns in environmental conditions, food availability, diet, size, and growth. Physical and biological data will be combined in bioenergetics models to estimate consumption and growth efficiency of juvenile pink salmon among regions, months and years, and bioenergetic growth potential will be mapped among sampling sites, water masses and regions through time to mechanistically examine the growth and survival consequences of different spatial-temporal distribution patterns and how interannual differences in the biophysical environment contribute to differences in survival and production of pink salmon in CGOA.
Study Objectives
- Contribute to development of a comprehensive database of pink salmon distribution, size, growth, diet, and associated biophysical condition data.
- Estimate useable measures of density and biomass of exploitable zooplankton taxa available to salmon.
- Use scale growth patterns to estimate individual growth trajectories and determine the interannual variability in the magnitude of stage-specific, size-selective mortality for pink salmon from PWS hatcheries, and develop a size-based preseason forecast of marine survival.
- Determine the interannual and monthly variation in diet composition of pink salmon among PWS and the different water masses in CGOA during July-October.
- Use bioenergetics models to estimate monthly consumption and growth efficiency of the major cohorts of pink salmon during May-Sept, using scale-based growth trajectories.
- Map inter-annual, monthly, and spatial variability in instantaneous growth potential for juvenile pink salmon at each sampling site in PWS and CGOA during July-August OCC and July-Sept/Oct Process and LTOP cruises (2001-2004).
- Connect summer growth and distribution to older winter-summer life stages (distribution, size).
Relevant Publications
Armstrong, J.L., J.L. Boldt, A.D. Cross, J.H. Moss, N.D. Davis, K.W. Myers, R.V. Walker, D.A. Beauchamp and L.J. Haldorson. 2005. Distribution, Size and Interannual, Seasonal and Diel Food Habits of the Northern Gulf of Alaska Juvenile Pink Salmon, Oncorhynchus gorbuscha. Deep-Sea Research II 52(1-2):247-265. (US GLOBEC Contribution 421).
Cross, A.D., D.A. Beauchamp, J.L. Armstrong, M. Blikshteyn, J.L. Boldt, N.D. Davis, L.J. Haldorson, J.H. Moss, K.W. Myers and R.V. Walker. 2005. Consumption demand of juvenile pink salmon in Prince William Sound and the coastal Gulf of Alaska in relation to prey biomass. Deep Sea Res. II 52(1-2):347-370. (US GLOBEC Contribution no. 475).
Moss, J. H., D. A. Beauchamp, A. D. Cross, K. W. Myers, E. V. Farley, Jr., J.M. Murphy, and J.H. Helle. 2005. Evidence that faster growth is associated with higher marine survival for pink salmon (Onchorhynchus gorbuscha). Transactions of the American Fisheries Society 134:1313-1322. (U.S. GLOBEC Contribution no. 252).
Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative Research (AYK SSI)
As a voluntary public service in 2003-2006, we provided guidance and technical advice to the Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative (AYK SSI), as part of the National Research Council’s “Committee on Review of the AYK Research and Restoration Plan for Salmon.”
Relevant Publications
National Research Council. 2004. Developing a research and restoration plan for Arctic-Yukon-Kuskokwim (western Alaska) salmon. National Academy Press, Washington, D.C. 208 p.
National Research Council. 2006. Review of the draft research and restoration plan for Arctic-Yukon-Kuskokwim (Western Alaska) salmon. National Academy Press, Washington, D.C. 58 pp.
Currently, we are partners in an AYK SSI research project attempting to develop a stock-specific forecast model for AYK Chinook Salmon (Investigators: J. Seeb, L. Seeb, D. Eggers, and W. Templin, Alaska Department of Fish and Game, Gene Conservation Laboratory; K. Myers and N. Davis, High Seas Salmon Research Program, SAFS, UW; Cooperating Investigators: E. Farley, Jr., and R. Wilmot, Auke Bay Laboratory, OCC Program).
Project Summary
Unanticipated declines of major stocks of Chinook salmon in Western Alaska prompt interest in marine migratory patterns and survival. Variable survival in the context of the changing marine environment confounds our ability to forecast run strength and manage these stocks. Additionally, record numbers of Chinook salmon were harvested as bycatch in the Bering Sea walleye pollock fishery in 2005. What impact might this bycatch have on returns to AYK drainages? A proposed run reconstruction model may offer critical insight into marine survival of AYK stocks of Chinook salmon, ultimately providing a forecast tool for improved management. First, National Marine Fisheries Service (OCC Program) marine surveys will provide juvenile (age 1.0) Chinook salmon in the eastern Bering Sea collected during the summers of 2002-2006; genetic stock composition analysis and abundance estimates will be used to approximate relative year class strength of contributing stocks. Then, stock composition and abundance of subadults (by age class) in the Bering Sea groundfish fishery Chinook salmon bycatch will be estimated. The reconstruction model will use a cohort analysis to test the utility of the juvenile data and bycatch data to forecast run strength of AYK stocks.
US Geological Survey (USGS) Global Change Research in Biology
The USGS participates in the US Global Change Research Program (USGCRP) in the area of biology. This work is conducted under the Biological Resources Division's (BRD) Ecosystems Program Element. BRD's global change activities contribute to the broader global change programs of the USGS and the Department of the Interior (DOI) and the U.S. Climate Change Science Program. A primary focus of BRD global change research and monitoring is on the effects of global change on DOI lands and resources. Research is conducted in several varied biogeographic regions and within specific thematic areas.
Currently, we are partners in a USGS BRD Alaska Biological Science Center (ABSC) Global Change Project, “Functional Linkages Between Climate, Anthropogenic Factors and the Epipelagic Community of the North Pacific Ocean (BRD Principal Investigator: J. Nielsen). This work involves collaborations with Natural Resources Consultants (G. Ruggerone), University of Washington (K. Myers, D. Beauchamp), Alaska Department of Fish and Game, Quinault Fisheries, Washington Department of Fish and Wildlife, NOAA Fisheries, the international Pacific Salmon Commission, and KamchatNIRO.
Project Summary
Salmon populations originating in Alaskan and Pacific Northwest rivers have undergone dramatic fluctuations in abundance during recent decades. These populations contributed to valuable commercial, sport, and native American fisheries when they were productive, but severe regional declines have resulted in significant economic and social costs and ecological impacts because salmon are important keystone species in riverine and adjacent terrestrial ecosystems and the epipelagic marine community. There is evidence that salmon survival is linked to large-scale climate fluctuations, but the underlying mechanism(s) remain largely inferential. Our working hypothesis is that critical life stage growth of salmon is a key linkage between climate change and salmon survival. Initial Global Change Project research developed time series of seasonal and annual Bristol Bay sockeye salmon growth during freshwater and marine life history stages using archived collections of salmon scales, which provide an index of growth. Several novel studies linking salmon growth to survival, climate change, and anthropogenic factors (i.e., hatchery production) were published. This project is continuing this innovative research in order to test several key climate/trophic dynamic hypotheses involving recent changes in Bristol Bay salmon growth and survival. This project will also expand our scale growth database to include sockeye salmon stocks from around the Pacific Rim in an effort to test hypotheses involving broad-scale climate effects on salmon growth and survival in freshwater and marine environments across the entire species range. Additionally, Chinook salmon scale growth patterns will be used to further test a recent hypothesis that survival of Puget Sound Chinook salmon, a threatened species, shifted from predation-based to competition-based mortality in response to climate-induced changes in the early 1980s and thereafter. Our investigations will provide significant progress toward understanding the effects of climate change and certain anthropogenic effects on salmon production.
Relevant Publications
Ruggerone, G.T., E. Farley, J. Nielsen, and P. Hagen. 2005. Seasonal marine growth of Bristol Bay sockeye salmon (Oncorhynchus nerka) in relation to competition with Asian pink salmon (O. gorbuscha) and the 1977 ocean regime shift. Fishery Bulletin 103:355-370.
Ruggerone, G.T., and J.L. Nielsen. 2004. Evidence for competitive dominance of pink salmon (Oncorhynchus gorbuscha) over other salmonids in the North Pacific Ocean. Reviews in Fish Biology and Fisheries. 14:371-390.
Ruggerone, G.T., M. Zimmermann, K.W. Myers, J.L. Nielsen, and D.E. Rogers. 2003. Competition between Asian pink salmon and Alaskan sockeye salmon in the North Pacific Ocean. Fish. Oceanogr. 3:209-219.
Joint Institute for the Study of the Atmosphere and Ocean (JISAO) Salmon Ecosystems Model
Currently, we are partners in a JISAO research project attempting to develop a North Pacific salmon ecosystems model (Principal Investigator: N. Mantua). Our role is to provide the best available scientific information on seasonal distribution and migration, and trophic interactions of regional stocks of Asian and North American salmon species migrating in the North Pacific Ocean and Bering Sea.
Project Summary
Drawing on widespread datasets, researchers will construct an integrated model of how salmon ecosystems operate at the scale of the North Pacific Ocean. The project is designed to provide credible information for use in salmon management and conservation decisions.
Washington Sea Grant (WSG) Steelhead Research
Funding for this 2007-2009 WSG project (Investigators: K. Myers, N. Davis, N. Mantua, and M. Fukuwaka), “Climate-change effects on steelhead in North Pacific marine ecosystems,” should be effective February 1, 2007, provided that the Congress appropriates adequate funding for the Sea Grant program.
Project Summary
The overarching goal of the proposed research is to increase scientific understanding of the biophysical mechanisms that affect survival of steelhead (Oncorhynchus mykiss) in North Pacific marine ecosystems. Dramatic fluctuations in the abundance of adult steelhead returning to rivers in the Pacific Northwest in 2000-2006 appear to be linked to climate effects on their ocean survival. We hypothesize that climate induced changes in ocean environmental conditions and food webs in offshore waters of the North Pacific Ocean are affecting ocean growth and survival of Pacific Northwest steelhead. Our proposal addresses National Sea Grant priorities for understanding ocean ecosystems, habitats, and the effects of natural and human-induced climate change, as well as regional priorities for conserving living marine resources and ensuring sustainable fisheries and healthy populations.