Great Lakes Laboratory for Fisheries and Aquatic Sciences, Fisheries and Oceans Canada, 867 Lakeshore Road, Burlington, ON L7R 4A6

Summary

         Lake Superior has the most depauperate fish fauna of all of the Great Lakes as a result of historical and environmental factors. Seventy-one native species, including three species endemic to the Great Lakes (Bloater, Kiyi, Shortjaw Cisco), and 15 non-native species are established in the Lake Superior basin. Historically, the fish fauna was exposed to threats related to overexploitation, habitat degradation and aquatic invasive species. Recently, habitat degradation and aquatic invasive species appear to be increasing threats, which may be exacerbated by climate change. In the future, non-native species will likely be added to the Lake Superior fish fauna through natural dispersal, and deliberate and accidental introduction through various pathways, and some of these species will likely become invasive. The successful establishment, spread and impact of these species will ultimately depend on the magnitude and extent of human-related vectors (e.g. ballast water, bait fish), dispersal capability, propagule pressure, extent of climate change and subsequent habitat change, and the nature of their interactions with species native to the lake.