Distribution and abundance of herring and other pelagic fish off the west coast of Vancouver Island in September, November, 1980, and March, 1981, and in the Strait of Georgia in November, 1980 / by F.H.C.... : Fs97-4/1682E-PDF

"Hydroacoustic cruises were carried out in September, November, 1980, and March, 1981, to determine the distribution and abundance of herring off the west coast of Vancouver Island. There were additional surveys in November in the Strait of Georgia to assess that spawning stock (which summers off the west coast), and in March in Barkley and Clayoquot Sounds to determine the abundance of west coast spawners. The timing of the cruises in relation to migration proved critical and was not satisfactorily attained. In September, 67,740 t of herring were found off the west coast, in November 53,700 t, and in March 33,465 t. In September an additional 10,480 t were located off Victoria. In all months most of the herring occurred south of Amphitrite Point, mainly along the outer edge of the shelf. In September almost half was south of the U.S./Canadian fishing boundary; however, the quantity in this area decreased sharply in November. Smaller concentrations occurred on La Perouse and Swiftsure Banks in September and November but in March the largest concentration was found in the latter area. Faulty equipment negated the results of the November Strait of Georgia survey. The surveys of Barkley and Clayoquot Sounds unfortunately occurred mainly after spawning, when most of the herring had left. In September 67,230 t of hake and 31,880 t of pollock were found in a broad band from Cape Beale Spit to the Juan de Fuca Trench. In November the quantity of hake had decreased to 33,870 t, presumably due to migration south. The quantity of pollock was essentially unchanged. In March, no hake were identified offshore although small amounts were found in the inlets. Dogfish increased from 10,120 t in September to 33,455 t in November and 38,590 t in March. In September the dogfish were mainly on the outer edge of the shelf, but by March were concentrated along the inner edge of the Prairie Grounds. Yellowtail and redstripe rockfish occurred in small quantities in September and November. The March estimates of rockfish are unreliable"--Abstract, page v.

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