Identifying Vulnerabilities of Riverine Fishes to Climate Change in the Great Lakes Region

Projections of climate change in the Great Lakes Region indicate warmer and wetter trends, with the potential for altering hydrologic functions of surface and ground water resources including elevated water temperature, decreased minimum instream flow, and increased peak events. This investigation integrated regional downscaled climate projections with fish models to estimate the effects of climatic change on the occurrence of 14 thermally representative fish species in the U.S. portion of the Upper Midwest and Great Lakes Landscape Conservation Cooperative (UMGL LCC) area.

Using a statistical classification procedure (RandomForests), a suite of habitat variables and 13 Global Circulation Models (GCMs) developed by University of Wisconsin’s Center for Climatic Research (UWCCR) were used to predict fish distributions for the current and future (2046-2065 and 2081-2100) time-periods. Utilizing this data, a web-based decision support mapper was built to help stakeholders estimate and visualize the potential consequences of climate change for stream fisheries at a variety of landscape scales. As part of this effort and taking into account all of the variability from using 13 different GCMs, this investigation developed a vulnerability score to measure and visualize the overall loss (vulnerability) or gain (opportunity) of species at a particular stream reach.