Gulf of Alaska | Fishes and Fish Habitats
Winter condition of juvenile salmon – Results from the IYS 2022 survey Presenter: Emily Fergusson , emily.fergusson@noaa.gov, NOAA Alaska Fisheries Science Center Todd Miller , todd.miller@noaa.gov, Ted Stevens Marine Research Institute (TSMRI), NOAA Alaska Fisheries Science Center Marine survival of juvenile Pacific salmon ( Oncorhynchus spp. ) has been linked to marine temperatures and feeding conditions during their first year in the ocean. Survival is a function of growth rate, size, and energetic status (fitness) that juvenile salmon attain during their first summer at sea. Evidence from previous winter surveys suggest that salmon fitness varies spatially, dependent on the ocean conditions such as temperature. The energetic status of Pacific salmon as they enter the Gulf of Alaska (GOA) in late summer is representative of their lipid reserves for use during winter when food is scarce. Therefore, understanding the spatial and inter-species variability in Pacific salmon energetic status throughout the GOA is important to understanding how oceanic conditions are influencing survival. In late winter of 2022, the International Year of the Salmon expeditions collected juvenile salmon in the GOA through a multi-vessel effort including scientists from five nations. Muscle samples were collected and analyzed for energy density, and percent lipid and protein. These three measures are used to assess if salmon were in a state of starvation. We also compared the winter salmon energy densities to those of salmon caught during the Alaska Fisheries Science Center’s summer juvenile surveys in Southeast Alaska and the Northern Bering Sea. The results of this study will increase our understanding of energetic status on the overwinter survival of Pacific salmon.
Alaska Marine Science Symposium 2023 198
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