Assessment of coho salmon from the Kenai River, Alaska, 1995
By: by Jamie A. Carlon and James J. Hasbrouck.
Contributors: Hasbrouck, James J.; Alaska. Division of Sport Fish. Statewide Research and Technical Services Unit.
Series: Fishery data series -- no. 97-7.
Publisher: Alaska Dept. of Fish and Game, Division of Sport Fish, Research and Technical Services Unit
Published: 1997
Place of publication: Anchorage
Language: eng
Number of pages: 68
Subjects: Coho salmon -- Alaska -- Kenai River -- Statistics.; Fishery resources -- Alaska -- Kenai River.; Fish tagging -- Alaska -- Kenai River.
Description: The commercial harvest of wild coho salmon Oncorhynchus kisutch of Kenai River origin in selected Upper Cook Inlet fisheries was estimated in 1995 based on the recovery of harvested adults marked with coded wire tags and adipose finclips. The goal of the study was to estimate the harvest of these fish in the drift gillnet fishery and the eastside set gillnet fishery of the Central District of Upper Cook Inlet. An estimated 6,956 (SE = 347) coho salmon from the Kenai River were harvested in the drift gillnet fishery and 13,165 (SE = 586) were harvested by the eastside set gillnet fishery. These commercial harvest estimates are the third available for coho salmon from the Kenai River. The harvests represented 3% of the total drift gillnet harvest of 234,126 coho salmon and 29% of the total eastside set gillnet harvest of 44,750 coho salmon. Harvest estimates in 1995 were similar to those estimated in 1993 and 1994. Geographic and temporal trends in harvest were also similar. Most (97%) coho salmon from the Kenai River were harvested during the last week of July through the second week of August. Geographic trends in the drift gillnet fishery could not be discerned because harvests delivered to processing locations were usually a mix of fish from multiple statistical areas. In the eastside set gillnet fishery, there was a general decreasing trend in the portion of the total harvest comprised of coho salmon from the Kenai River from the southernmost statistical area to the northernmost. Coded wire tags recovered from the drift gillnet fishery were also examined to determine the effect of fishery restrictions on the harvest of coho salmon from the Kenai River. The harvest of coho salmon of Kenai River origin during restricted fishing periods did not increase even though the restriction concentrated fishing effort closer to the mouth of the Kenai River. About 170,000 coho salmon smolt were marked in 1994 at the Moose River, a tributary to the Kenai River. The marked portion of the 1995 adult inriver return, as measured from sport harvest samples, ranged from 0.18 to 0.32 among weekly periods during the sport fishery (August 1 through September 20, 1996). Although it is not known if the sport harvest was sampled in proportion to harvest over time, smolt emigrating from the Moose River mixed with unmarked fish from across the Kenai River drainage prior to sampling the adult return in 1995 to such an extent that a relatively unbiased estimate of the portion marked (0.27) was obtained for the purpose of estimating commercial harvest. Based on the number of smolt marked, the number of sport harvested adults examined for marks, and the number of marked adults observed, an estimated 628,909 (SE = 14,788) coho salmon smolt emigrated from the Kenai River in 1994. Precise placement of coded wire tags through proper selection of tag injector headmolds likely resulted in the low tag loss rate of 3% during the experiment.
Notes: "February 1997"

Includes bibliographical references (p. 42-45)

Also issued online.

Partially financed by the Federal Aid in Sport Fish Restoration Act (16 U.S.C. 777-777K) ... Project F-10-11, Job no. S-2-14.