To better understand how density-dependent growth of ocean-dwelling Pacific salmon varied with climate and population dynamics, we examined the marine growth of sockeye salmon in relation to an index of sockeye salmon abundances among climate regimes, population abundances, and body sizes under varied life history stages, from 1925 to 1998 using ordinary least squares and multivariate adaptive regression spline threshold models. The annual marine growth and body size during the juvenile, immature, and maturing life stages were estimated from increments on the scales of adult age 2.2 sockeye salmon that returned to spawn at Karluk River and Lake on Kodiak Island, Alaska. Intra-specific density-dependent growth was inferred from inverse relationships between growth and sockeye salmon abundance based on commercial harvest. Density-dependent growth occurred in all marine life stages, during the cool regime, at lower abundance levels, and at smaller body sizes at the start of the juvenile life stage. The finding that density-dependence occurred during the cool regime and at low population abundances suggests that a shift to a cool regime or extreme warm regime at higher population abundances could further reduce the marine growth of salmon and increase competition for resources. Alaska salmon production fluctuates with climate and ocean conditions in the North Pacific Ocean. In this study, we evaluated the hypothesis that faster marine growth was related to higher survival as a consequence of more favorable ocean conditions for growth during the 1927-46 and 1977-2000 warm regimes, and slower growth was related to lower survival as a consequence of less favorable climatic and oceanic conditions for growth during the 1947-76 cool regime. We measured and compared the annual growth on scales collected from age 2.2 sockeye salmon that returned to Karluk Lake on Kodiak Island, Alaska from 1927 to 2000 to regime periods, climatic and oceanic indices, and survival. First and second marine-year scale growth fluctuated with the cool regime and recent warm regime. Survival estimated as the ratio of offspring to parental escapement was lower during the 1925-46 warm regime and 1947-76 cool regime. Survival was positively related to first and second marine year scale growth, eastern North Pacific atmospheric circulation, and reduced winter and spring coastal downwelling in the Gulf of Alaska. Winter and spring climatic and oceanic conditions influences on first and second year marine growth of Karluk Lake sockeye are a possible mechanisms linking Karluk Lake sockeye salmon survival to climate over the past half century.

A time series of scale samples (1956 b?? 2002) collected from adult sockeye salmon returning to Ugashik River were retrieved from the Alaska Department of Fish and Game. These scales were digitized, revealing growth information for the freshwater and marine life history stages of sockeye salmon. The growth information will be related to time series of sockeye salmon production to Bristol Bay and oceanographic conditions within the Bering Sea and North Pacific Ocean.

A time series of scale samples (1956 2002) collected from adult sockeye salmon returning to Naknek River were retrieved from the Alaska Department of Fish and Game. These scales were digitized, revealing growth information for the freshwater and marine life history stages of sockeye salmon. The growth information will be related to time series of sockeye salmon production to Bristol Bay and oceanographic conditions within the Bering Sea and North Pacific Ocean.

Annual data are collected as part of smolt trapping operations using fish trapping methods. Traps collect emigrating salmon smolts to identify cohort bio-characteristics, run timing information, as well as enumerating migrating fish.

Ecosystem-based fisheries management requires the development of physical and biological time series that index ocean productivity for stock assessment and recruitment forecasts for commercially important species. Since recruitment in marine fish is related to ocean condition, we developed proxies for ocean conditions based on sea surface temperature and biometric measurements of chum salmon (Oncorhynchus keta) captured in the walleye pollock (Gadus chalcogrammus) fishery in the eastern Bering Sea in three periods (July 16-30, September 1-15, and September 16-30). The main purpose of this paper was to evaluate Pacific salmon (Oncorhynchus spp.) growth as a possible indicator of ocean conditions that, in turn, may affect age-1 pollock recruitment. Marine growth rates of Pacific salmon are the result of a complex interplay of physical, biological, and population-based factors that fish experience as they range through oceanic habitats. These growth rates can therefore be viewed as indicators of recent ocean productivity. Thus, our hypothesis is that estimated intra-annual growth in body weight of immature and maturing age-4 male and female chum salmon may be used as a biological indicator of variations in rearing conditions also experienced by age 0 walleye pollock; consequently, they may be used to predict the recruitment to age-1 in walleye pollock. Summer SSTs and chum salmon growth at the end of July and September explained the largest amount of variability in walleye pollock recruitment indicating that physical and biological indices of ocean productivity can index fish recruitment.

FY20 will mark the 23nd year of sampling, making the Juvenile Salmon and Ocean Ecosystem Survey (JSOES) the longest running salmon survey on the west coast. JSOES has clearly demonstrated correlations between ocean conditions and the distribution, abundance, and survival of juvenile Columbia River (CR) salmon in the Northern California Current (NCC) nearshore ecosystem. For example, our ocean indicators provide managers from the federal and state governments, tribes, and other agencies/groups the ability to forecast adult returns one to two years in advance for coho and spring/summer Chinook salmon. We continue to show the importance of evaluating ocean conditions to support management decisions and to provide context for efforts by the Northwest Power and Conservation Council (NWPCC) and BPA to restore and enhance salmon production. The primary goal of our work is to develop a mechanistic understanding of how trophic dynamics and conditions in the ocean and CR plume affect survival of juvenile salmonids. This knowledge will allow us to improve forecasts in a quantitative rather than qualitative manner, and decouple the effects of mitigation efforts in the freshwater environment from the effects of a changing ocean environment. These improved forecasts will lead to well-informed recommendations for an ecosystem approach to management strategies based on the full suite of river, plume, and ocean environments. Lab Lengths, weight, genetics, IGF-1 (growth), and otolith microchemistry from juvenile salmonids.

FY20 will mark the 23nd year of sampling, making the Juvenile Salmon and Ocean Ecosystem Survey (JSOES) the longest running salmon survey on the west coast. JSOES has clearly demonstrated correlations between ocean conditions and the distribution, abundance, and survival of juvenile Columbia River (CR) salmon in the Northern California Current (NCC) nearshore ecosystem. For example, our ocean indicators provide managers from the federal and state governments, tribes, and other agencies/groups the ability to forecast adult returns one to two years in advance for coho and spring/summer Chinook salmon. We continue to show the importance of evaluating ocean conditions to support management decisions and to provide context for efforts by the Northwest Power and Conservation Council (NWPCC) and BPA to restore and enhance salmon production. The primary goal of our work is to develop a mechanistic understanding of how trophic dynamics and conditions in the ocean and CR plume affect survival of juvenile salmonids. This knowledge will allow us to improve forecasts in a quantitative rather than qualitative manner, and decouple the effects of mitigation efforts in the freshwater environment from the effects of a changing ocean environment. These improved forecasts will lead to well-informed recommendations for an ecosystem approach to management strategies based on the full suite of river, plume, and ocean environments. Nekton and juvenile salmon collections from surface trawl.

Pacific salmon (Oncorhynchus spp.) runs in rivers that flow into the eastern Bering Sea have been inconsistent and at times very weak. Low returns of chinook (O. tshawytscha) and chum (O. keta) salmon to the Yukon River, Kuskokwim River, and Norton Sound areas of Alaska prompted the state of Alaska to restrict commercial and subsistence fisheries during 2000 and declare the region a fisheries disaster area. Weak salmon returns to these river systems follow several years of low sockeye (O. nerka) salmon returns to Bristol Bay, which was declared a fisheries disaster region during 1998 by both the State of Alaska and the U.S. Department of Commerce. Causes of the poor salmon returns to these river systems are not known however, the regional-scale decline of these stocks indicates that the marine environment may play a critical role. Ocean conditions, particularly in the first few months after the salmon leave fresh water, are known to significantly affect salmon survival (Holtby et al. 1990; Friedland et al. 1996; Beamish and Mahnken 2001). Mechanisms affecting marine survival of the eastern Bering Sea salmon stocks are unknown, principally due to the lack of marine life history information on western Alaska salmon. To improve understanding of the marine life-history stage of salmon in the Bering Sea, the North Pacific Anadromous Fish Commission (NPAFC) began an internationally coordinated research program on salmon in the Bering Sea called the Bering-Aleutian Salmon International Survey (BASIS) (NPAFC 2001). As part of BASIS, scientists from the National Marine Fisheries Service (NMFS), Ocean Carrying Capacity (OCC) program conducted a fall survey on the eastern Bering Sea shelf to provide key ecological data for eastern Bering Sea salmon stocks during their juvenile life-history stage. The goal of the OCC/BASIS salmon research cruise was to understand mechanisms underlying the effects of environment on distribution, migration, and growth of juvenile salmon on the eastern Bering Sea shelf. Primary objectives of BASIS include: 1) to determine the extent of offshore migrations of juvenile salmon from rivers draining into the eastern Bering Sea, 2) to describe the physical environment of the eastern and northeastern Bering Sea shelf occupied by juvenile salmon, and 3) to collect biological information on other ecologically important species. Summaries of previous Bering Sea juvenile salmon research cruises can be found in Farley et al. (1999, 2000, 2001, 2002, 2004, 2005).

Annual telemetry data are collected as part of specific projects (assessments within watersheds) or as opportunistic efforts to characterize Atlantic salmon smolt migration dynamics. Telemtry projects have since expanded to include the tracking of a variety of non-Atlantic salmon species.

The Hook and Line Survey will collect species-specific aggregate weight and abundance, as well as individual lengths and biological characteristics (e.g., age, maturity, genetics, diet, energetics). Tagging will also be conducted opportunistically and by request. In addition to deploying hook and line gear, the survey will deploy a benthic stereo camera system to collect additional information on fish density, abundance, and demographics. A suite of environmental data will be collected via conductivity, temperature, and depth (CTD) deployments at each survey station. Habitat data will be collected using seafloor imaging (still or video) techniques. Finally, operational and gear deployment data will be collected for every gear set. The Hook and Line Survey is a new survey, so all data uses are prospective. Once the survey is mature, the data will be used in stock assessments for a variety of commercially and recreationally important species and for analyses that support management actions. This will encompass species covered by the Mid-Atlantic Fishery Management Council (MAFMC), New England Fishery Management Council (NEFMC), and Atlantic States Marine Fisheries Commission (ASMFC), including but not limited to Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), pollock (Pollachius pollachius), white hake (Urophycis tenuis), red hake (Urophycis chuss), summer flounder (Paralichthys dentatus), scup (Stenotomus chrysops), black sea bass (Centropristis striata), bluefish (Pomatomus saltatrix), spiny dogfish (Pomatomus saltatrix), Atlantic croaker (Micropogonias undulatus), and skates. At least 5 years of Hook and Line Survey data will be required before abundance indices from the survey are integrated into stock assessments, but habitat and biological data could be used immediately to supplement existing data streams. Beyond stock assessments and management, the data from the Hook and Line Survey will also be used in research to understand the cumulative impacts of offshore wind on resource species and their habitats. Note that the Hook and Line Survey is a new survey and is still in planning and review. The exact geographic extent and survey strata are still under review. The geographic extent displayed here is tentative.