Abstract

The Highseas Salmon program of Fisheries and Oceans Canada conducted a survey of Pacific salmon in the Gulf of Alaska from October 4- 30, 2000. 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. Oceanographic, fish and zooplankton sampling was conducted at stations spanning the area from Laperouse Bank, off the westcoast of Vancouver Island (48.6°N) to Icy Strait, Southeast Alaska (58.3°N).

A total of 5815 Pacific salmon were caught on the survey. Of these, 5512 were juvenile pink (O. gorbuscha), chum (O. keta), coho salmon (O. kisutch), and sockeye (O. nerka) salmon in their first summer in the ocean and 280 were chinook salmon (O. tshawytscha) under 350mm in fork length.

Juvenile pink (age 0.0) and chum (age 0.0) were caught within the range of 1 – 1000 fish per tow, and juvenile sockeye (age X.0) were caught within the range of 1-100 fish per tow primarily along the juvenile salmon migration corridor through Queen Charlotte Sound, Hecate Strait, Dixon Entrance, and the shelf off Southeast Alaska.

Juvenile coho (age X.0) were caught within the range of 1-100 fish per tow throughout survey.

Chinook less than 350mm in fork length were caught within the range of 1-10 fish per tow in all the regions on the suvey except Icy Strait, Southeast Alaska. Here, they were caught within the range of 1-100 fish per tow.

Juvenile pink, chum, sockeye, and coho all progressively increased in size from the west coast of Vancouver Island, to central regions that include Queen Charlotte Sound and Hecate Strait, to northern regions that include Dixon Entrance, Southeast Alaska, and inside Southeast Alaska.