Abstract

The Highseas Salmon program of Fisheries and Oceans Canada conducted a survey of Pacific salmon in the Gulf of Alaska during February 14-26, 2003. 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 Barkley Sound on the west coast of Vancouver Island in southern British Columbia (48.8°N) to the southern end of Chatham Strait in Southeast Alaska (56.7°N).

Unfortunately, the CCGS W. E. Ricker’s diesel engine broke down on February 26 forcing the cancellation of the remainder of the survey. We were unable then to carry out the plan to conduct more extensive sampling along the inside passageways in Southeast Alaska.

A total of 1113 Pacific salmon were caught on the survey. Of these, 380 were juvenile pink (O. gorbuscha) (age 0.1), 465 were juvenile chum (O. keta) (age 0.1), 39 were juvenile sockeye (O. nerka) (age X.1), and 70 were juvenile coho salmon (O. kisutch) (age X.1) in their first winter in the ocean, and 155 were chinook salmon (O. tshawytscha) under 300 mm in fork length.

Juvenile pink, chum, and sockeye were caught on the shelf on the west coast of Vancouver Island, and along McIntyre Bay in Dixon Entrance. All the juvenile sockeye caught in Dixon Entrance were Fraser River stocks based on a subsequent analysis of genetic markers. Juvenile coho were caught primarily on the shelf and within the inlets on the west coast of Vancouver Island. One juvenile coho was caught in Dixon Entrance, which was the only one caught north of Vancouver Island on four end-of-winter surveys conducted by the Highseas Salmon program since year 2000. Juvenile chinook under 300 mm in fork length were caught primarily on the shelf and within the inlets on the west coast of Vancouver Island.