Ecology of slimy sculpin (Cottus cognatus) in the Chena River, Alaska

• Main Author: Sonnichsen, Sandra K.
• Format: Thesis
• Language: English
• Published: 1981
• Subjects: Fairbanks; Cottus cognatus; Alaska; Slimy sculpin
• Online Access: http://hdl.handle.net/11122/7403

Thesis (M.S.) University of Alaska Fairbanks, 1981 The purpose of this study was to gather information on the ecology of slimy sculpin (Cottus cognatus) in the upper Chena River. Three major topics were examined: age and growth, food habits, and habitat preferences. Age of fish was analyzed by length frequency and otoliths. Chena River sculpin were slow growing, reaching a maximum length of 86 mm in 7 years. Stomach contents were examined to determine contribution of different prey to the diet. Chironomids and large mayflies were most important in the diet; electivity indices indicated positive selection for them. Habitat preferences were examined by capturing fish, and measuring habitat variables at the point of capture. These data were analyzed using multiple regressions on principal components. No significant correlation was found between number of sculpin caught and habitat variables of depth, velocity, and substrate type.