Evaluation of a thermal habitat volume model for estimation of sustained yield for lake trout in selected lakes of southwest Alaska, 1994-95
By: by Michael Jaenicke, ... [et al.].
Contributors: Jaenicke, Michael Jon.; Alaska. Division of Sport Fish.
Series: Fishery data series -- no. 96-40.
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: 49
Subjects: Lake trout -- Habitat.; Lake trout -- Alaska, Southwestern.
Description: This was a 2-year study to evaluate the thermal habitat volume (THV) model for estimating sustained yield for lake trout Salvelinus namaycush in 15 lakes in Southwest Alaska. During 1994 bathymetric profiles were taken at three study lakes where no bathymetric maps existed. Temperature profiles were collected from 14 study lakes in 1994 and 10 study lakes in 1995. Bathymetric maps of the 15 study lakes were digitized into electronic files, and provided a useful method for estimating THV based upon the temperature data. The THV for lake trout is defined as the volume of water found between 12C and 8C. In previous studies a strong relationship has been found between the July THV and the sustained yield of lake trout in Ontario, Canada and Southcentral Alaska. THVs in this study resulted in estimates of sustained yield of lake trout ranging from 0.6 kg/ha/yr in lower Ugashik Lake to 6.4 kg/ha/yr in Lower Twin Lake. On average, the THVs from Southwest Alaska lakes are higher than the THVs found for similar sized lakes in Ontario, Canada, and Southcentral Alaska, and are most likely the result of lack of lake stratification in the Southwest Alaska lakes while the Ontario and Southcentral lakes do stratify during the summer months. The Southwest Alaska lakes currently receive little or no fishing pressure, so the accuracy of the sustained yield estimates could not be substantiated through historic harvest records. Recommendations were made to reduce the study to only those lakes with reliable harvest information based on the Statewide Harvest Survey and where temperature data can be collected in a cost efficient manner.
Notes: "November 1996"

Includes bibliographical references (p. 15-17)

Also issued online.