Spawning abundance of chinook salmon in the Taku River in 1995
By: by Scott A. McPherson....[et al.].
Contributors: McPherson, Scott A.; Alaska. Division of Sport Fish.
Series: Fishery data series -- no. 96-36.
Publisher: Alaska Dept. of Fish and Game, Division of Sport Fish, Research and Technical Services
Published: 1996
Place of publication: Anchorage
Language: eng
Number of pages: 25
Subjects: Chinook salmon -- Alaska -- Taku River -- Statistics.; Fish tagging -- Alaska -- Taku River -- Statistics.; Fish populations -- Alaska -- Taku River -- Statistics.; Chinook salmon -- Spawning.
Description: A cooperative study between the Alaska Department of Fish and Game, the Taku River Tlingit First Nation, and the Canadian Department of Fisheries and Oceans was conducted to estimate abundance of spawning of chinook salmon Oncorhynchus tshawytscha in the Taku River in 1995 with a mark-recapture experiment. Fish were captured at Canyon Island on the lower Taku river with fish wheels from May through August and were individually marked with metal jaw tags or back-sewn spaghetti tags and were batch marked as well with an opercle punch plus removal of the left axillary appendage. Sampling on the spawning grounds in tributaries was used to estimate the fraction of the population that had been marked. Abundance of chinook salmon 401659 mm long (mid-eye to fork of tail) was estimated directly from the mark-recapture experiment to be 32,246 (SE = 3,751). Abundance of fish larger than 659 mm was estimated by expanding the estimate for smaller fish by size composition of fish sampled on the spawning grounds. Estimated abundance of larger fish ( 660 mm) in 1995 was 33,805 (SE = 5,060). Estimated abundance of these larger fish from aerial surveys of parts of the Taku River was considerably smaller than estimates expanded from the mark-recapture experiment in 1995, a trend repeated from similar studies in 1989 and 1990. The 1991 brood year (mostly age 1.2) constituted 47% of the spawning population, followed by the 1989 brood year (mostly age 1.4), which constituted 31% of the population.
Notes: "November 1996"

Includes bibliographical references (p. 15-16)

Also issued online.