Stock-Structured Distribution of Western Alaska and Yukon Juvenile Chinook Salmon (Oncorhynchus tshawytscha) from United States BASIS Surveys, 2002–2007

• Main Authors: James M. Murphy, William D. Templin, Edward V. Farley, James E. Seeb
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Bering Sea; Gulf of Alaska; Yukon; Kuskokwim; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.155.4921; http://www.npafc.org/new/publications/Bulletin/Bulletin%20No.%205/NPAFC_Bull_5_051-059(Murphy).pdf

tshawytscha) using stock-structured distribution data from United States Bering-Aleutian Salmon International Surveys (BASIS), 2002–2007. Juvenile Chinook salmon were distributed within water depths less than 50 m and their highest densities were found close to river mouths of primary Chinook salmon-producing rivers in the eastern Bering Sea (Yukon, Kuskokwim, and Nushagak rivers) through their first summer at sea. This reflects a later marine dispersal from freshwater entry points than typically found in Gulf of Alaska stream-type Chinook salmon and resulted in the presence of juvenile Chinook salmon in shallow, non-trawlable habitats during the surveys. Juvenile Chinook salmon stock proportions in the northern shelf region (north of 60°N) were: 44 % Upper Yukon, 24 % Middle Yukon, 31 % Coastal Western Alaska, and 1 % other western Alaska stock groups. Juvenile Chinook salmon stock proportions present in the southern shelf region (south of 60°N) were: 95 % Coastal Western Alaska, 1 % Upper Yukon, and 4 % other western Alaska stock groups. It is believed that these stock mixtures do not support significant northward migration of stocks from the southern shelf, and reflect limited mixing of salmon from the two production regions during their first summer at sea. Spatial distribution patterns and coded-wire