The Role of Non-Native Lake Trout in Food Webs of Large Western Lakes

Non-native lake trout attract popular trophy fisheries in large western lakes and reservoirs, but have also fundamentally altered the structure and function of recipient systems, and have resulted in severe declines or extirpation of native salmonids in some cases.  Lake trout were introduced into many large western lakes in North America over the past century, but often remained at relatively low abundance for many years until a second non-native species Mysis diluviana became established in the basins as well. We quantified and compared the feeding ontogeny of lake trout among a selection of western lakes to examine their role in influencing these food webs.  We also examined biotic and abiotic factors that potentially mediate the abundance of non-native lake trout and their to regulate prey populations in different systems.