Development and Use of High-Resolution, Crowd-Sourced Stream Temperature Scenarios to Delineate Climate Refugia for Preserving Native Trout

Native trout are culturally and ecologically important but likely to continue declining this century as some of the cold-water environments they require are invaded by non-native species and shrink in association with global warming. Much can be done to preserve these fish but efficient planning and targeting of conservation resources requires precise information about which streams are most likely to support native populations later this century. Because native trout species like bull trout and cutthroat trout can persist in especially cold streams that are resistant to invasions, identifying those areas that are also capable of withstanding climate change would highlight refugia important for conservation planning. We demonstrate how high-resolution NorWeST stream temperature scenarios (website: http://www.fs.fed.us/rm/boise/AWAE/projects/NorWeST.shtml) can be used with crowd-sourced biological datasets to develop accurate species distribution models and forecasts about stream refuge locations across all streams in the Northern Rocky Mountains (Climate Shield website: http://www.fs.fed.us/rm/boise/AWAE/projects/ClimateShield.html). Knowledge about refuge locations may enable their protection, be used to rally support among multiple stakeholders, and provide a basis for climate-smart planning of conservation networks. The “climate shield” approach is generalizable to other areas because it has a strong physiological basis, relies on nationally available geospatial data, and mines existing datasets.