Sea-run and resident cutthroat trout and sea-run Dolly Varden population status at Lake Eva, southeast Alaska, during 1995
By: by Richard J. Yanusz and Artwin E. Schmidt.
Contributors: Schmidt, Artwin E.; Alaska. Division of Sport Fish.
Series: Fishery data series -- no. 96-47.
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: 40
Subjects: Cutthroat trout -- Alaska -- Eva Lake -- Statistics.; Dolly Varden (Trout) -- Alaska -- Eva Lake -- Statistics.; Fish populations -- Alaska -- Eva Lake -- Measurement.
Description: Suspected declines in cutthroat trout Oncorhynchus clarki abundances in Southeast Alaska and a history of thorough research in the 1960s at the Lake Eva system (Baranof Island) prompted a re-examination of the system in 1995. All sea-run cutthroat trout and Dolly Varden Salvelinus malma exiting the Lake Eva system between 14 April and 31 July 1995 were counted at a weir on the lakes outlet. A total of 2,562 cutthroat trout and 117,821 Dolly Varden passed downstream through the weir, and were defined as sea-run. These numbers far exceeded the historical emigrations observed in the 1960s at Eva Creek. The mean fork lengths of 303 mm for sea-run cutthroat trout and 304 mm for sea-run Dolly Varden during 1995 were also greater than those recorded during the early 1960s, which were 284 mm and 253 mm fork length, respectively. Dolly Varden age 6 and less in 1995 tended to be larger at age than in 1963. Year-class and other effects contributed to these results. Cutthroat trout present in Lake Eva during July (when adult sea-run trout are essentially absent) were defined as residents, and a two-event, mark-recapture method was used to estimate that 2,154 (SE 274) cutthroat trout 180 mm fork length were present. Mean fork length of resident trout 180 mm was 240 mm. The density and the length distribution of resident cutthroat trout in Lake Eva did not appear substantially different from other cutthroat trout populations in Southeast Alaska.
Notes: "December 1996"

Includes bibliographical references (p. 26-29)

Also issued online.