Short-Term Survival of Lake Trout Released from Commercial Gill Nets in Lake Superior

Abstract

We investigated the short-term survival of lake trout Salvelinus namaycush released from tribal commercial gill nets during 1993 and 1994. Survival was estimated by holding released fish in tanks for 48 h. Survival of released fish was estimated as 68% during winter, 77% during spring, and 70% during summer. Overall survival for all fish captured in the sampled gill-net lifts was estimated to be 21% (95% confidence interval, CI = 18–24%) during winter; 31% (CI = 26–36%) during spring; and 22% (CI = 18–27%) during summer. Lake trout larger than 25.0 in (total length) survived better than smaller lake trout. Fishing season, number of nights set, time between capture and holding, and manner of entanglement had no significant (P > 0.05) effect on survival. Our findings enhance the understanding of lake trout survival after release from commercial gill-net catches. Information from this study can be used to estimate postrelease survival of released fish.