Projected Vulnerability of Brook Trout to Climate and Land Use Changes in the Eastern U.S. (Regional Assessment)

Throughout its native range in the Eastern U.S., the brook trout is a culturally and economically important species that is sensitive to warming stream temperatures and habitat degradation. The purpose of this assessment was to determine the impacts that projected future land use and climate changes might have on the condition of stream habitat to support self-sustaining brook trout populations. The study region encompassed the historic native range of brook trout, which includes the northeastern states and follows the Appalachian Mountains south to Georgia, where the distribution is limited to higher elevation streams with suitable water temperatures. Relationships between recent observations of brook trout and predicted stream temperature, land use, and a number of potential habitat stressors were used to make predictions regarding the condition of the habitat in each stream reach for supporting self-sustaining brook trout populations now and under future climate and land use change scenarios. The objectives of this project were to (1) develop a stream temperature model and predict water temperature for all stream reaches in the Eastern Brook Trout Joint Venture (EBTJV) region under present conditions and future scenarios of climate and land use change; (2) predict the occurrence of brook trout in all stream reaches of the EBTJV region based on relationships with natural landscape predictors, predicted stream temperature, and land use under present conditions and future scenarios of climate and land use change; and (3) provide maps and characteristics of stream reaches where stream temperatures and suitability for brook trout are predicted to change under climate and land use change scenarios. Further, to help meet local and regional management needs, researchers aimed to (1) identify thresholds of land use that might preclude self-sustaining brook trout populations at a regional scale; (2) identify management practices that might help mitigate climate change impacts at a regional scale, and (3) use case studies to discuss properties associated with vulnerability in the region.