by Alaska Dept. of Fish and Game, Division of Sport Fish, Research and Technical Services in Anchorage .
Written in English
Suspected declines in cutthroat trout Oncorhynchus clarki abundances in Southeast Alaska and a lack of research at the Sitkoh system (Chichagof Island) prompted an examination in 1996. A weir was operated on Sitkoh Creek just above salt water from 31 March to 29 June 1996, and a total of 3,955 sea-run cutthroat trout and 48,252 sea-run Dolly Varden Salvelinus malma emigrated. All cutthroat and steelhead trout Oncorhynchus mykiss and a sample of the Dolly Varden were measured for length. The mean fork length for sea-run cutthroat trout was 284 mm and for Dolly Varden was 266 mm (SE 1.8). The abundance and length distribution of sea-run cutthroat trout and Dolly Varden in the Sitkoh system appears similar to other sea-run populations in Southeast Alaska. A total of 926 steelhead trout was passed upstream, which exceeded all but one of the five years of historical data (range 520-1,108). Scars on steelhead thought to be due to fishing gear occurred one-third as frequently in 1996 as in 1993. The length distribution of steelhead in 1996 appears similar to that in the historical data. The proportion of steelhead observed during foot surveys in 1996 (0.22) was over twice the proportions observed in 1982 and 1993 (0.086 and 0.085, respectively), likely due to ideal conditions in 1996, and snorkel surveys observed about twice the proportion (0.48) as did foot surveys conducted at the same time.
|Statement||by Richard J. Yanusz.|
|Series||Fishery data series -- no. 97-23.|
|Contributions||Alaska. Division of Sport Fish.|
|The Physical Object|
|Pagination||ii, 33 p. :|
|Number of Pages||33|