Abstract

The Highseas Salmon program of Fisheries and Oceans Canada conducted a survey of Pacific salmon in the Gulf of Alaska during June 14-24, 2001. The objectives of the surveys were to (1) evaluate the distribution and ecology of juvenile Pacific salmon (Oncorhynchus spp.) during their first year in the ocean, (2) describe the ambient oceanographic conditions, and (3) quantify the biomass of zooplankton, an important prey for Pacific salmon at sea. Fish, oceanographic, and zooplankton sampling was conducted at stations spanning the area from the west coast of Vancouver Island (48.5°N) to Southeast Alaska (56°N).

A total of 1587 Pacific salmon were caught on the survey. Of these, 398 were juvenile pink (O. gorbuscha), chum (O. keta), coho (O. kisutch), and sockeye (O. nerka) salmon in their first summer in the ocean and 81 were chinook salmon (O. tshawytscha) under 300mm in fork length.

Juvenile sockeye and coho, and chinook under 300mm in forklength, were caught on the continental shelf within the 1000 m isobath along the entire coastal length of the survey from Washington State to Southeast Alaska. Juvenile pink and chum were scarce, which indicates that they were probably just beginning to move onto the shelf.

Adult pink, chum, sockeye, coho, and chinook over 300mm in fork length were caught both on the shelf and offshore throughout the range of the survey, and catches for all five species were particularly consistent off Southeast Alaska.