Production of coho salmon from the Taku River, 1997-1998
By: by Richard J. Yanusz, Scott A. McPherson, and David R. Bernard.
Contributors: McPherson, Scott A.; Bernard, David R.; Alaska. Division of Sport Fish.
Series: Fishery data series -- no. 99-34.
Publisher: Alaska Dept. of Fish and Game, Division of Sport Fish
Published: 1999
Place of publication: Douglas, AK
Language: eng
Number of pages: 42
Subjects: Coho salmon -- Alaska -- Taku River -- Statistics.; Fish populations -- Alaska -- Taku River -- Measurement.; Fishes -- Alaska -- Taku River -- Statistics.
Genres: Statistics.
Other titles: Federal aid in sport fish restoration (Alaska)
Description: Recovery of coded wire tags from adults in 1998 tagged as smolts in 1996 and 1997 and an inriver abundance program were used to estimate smolt abundance, harvest, exploitation rate, and production of coho salmon Oncorhynchus kisutch from the Taku River, near Juneau, Alaska. From 15 April through 23 June 1997, 23200 baited G-40 minnow traps were fished daily near Canyon Island on the Taku River. During this period, 15,364 coho salmon smolt 70 mm fork length were marked with an adipose fin clip and a coded wire tag of code 04-46-40 or 04-46-41, and released alive. Smolt averaged 86mm in fork length (SE = 0.52) and 6.6 g (SE = 0.14) in weight. In 1998, 232 adult coho salmon bearing coded wire tags of Taku River origin were recovered in random sampling of marine fisheries, and correspond to an estimated harvest of 53,368 (SE=7,435) in U. S. marine waters. Of this harvest, the troll fishery took an estimated 54%, drift gillnet fisheries took 36%, recreational fisheries 8%, and seine fisheries 1%. An estimated 66,472 (SE = 5,394) adults passed by Canyon Island, as determined by a separate mark-recapture experiment. Of this inriver run, 5,090 were harvested by inriver fishers above the U.S./Canada border, leaving an estimated escapement past all fisheries of 61,382 (SE = 5,394). The estimated run (escapement plus harvest) in 1998 for coho salmon originating above Canyon Island was 119,840 (SE = 9,186); marine exploitation rate on this run was an estimated 44.5% (SE=4.0%). The estimated run in 1998 for coho salmon from the entire Taku River drainage was 153,641 (SE 11,776), accounting for those fish originating below Canyon Island. The contribution of all Taku River coho salmon to the Juneau marine sport fishery was estimated at 5,108 fish (SE = 1,390), or 32% of the estimated harvest in that fishery. Estimated smolt abundance in 1997 from above Canyon Island was 853,662 (SE = 147,260), obtained by using a modified Petersen estimator, and marine survival rate of coho salmon smolt from above Canyon Island was estimated at 14% (SE = 2.6%).
Notes: "December 1999."

Includes bibliographical references (p. 21-22).

Also issued online.

Partially financed by the Federal Aid in Sport Fish Restoration Act ... under Projects F-10-12 and F-10-14, Job No. S-1-3(a).