Climate change vulnerability assessment is a method for estimating the extent to which species are exposed to changes in climate across different parts of their range, as well as their ecological sensitivities to those changes. With this information, researchers can assess the consequences of past climate variability and future climate change for species of conservation concern and can study how these consequences may vary across a specie’s range. In collaboration with the Climate Change Ecology Lab at the University of Wisconsin-Madison and the Wisconsin Department of Natural Resources, an ecologist at the Forest Service’s Eastern Forest Environmental Threat Assessment Center developed full life cycle, spatial population models to perform vulnerability assessments for Eastern Massasauga Rattlesnake (Sistrurus catenatus), Ruffed Grouse (Bonasa umbellus), and Henslow's Sparrow (Ammodramus henslowi). Findings, while surprising in some cases, have helped researchers develop management recommendations by identifying climate refugia as well as high-risk regions. For example, it is commonly assumed that as the climate warms, optimal conditions for northerly species will shift farther north. However, the team found that Henslow's Sparrow was more sensitive to precipitation across its midwestern grassland habitat, and that shifts in precipitation patterns are expected to result in more southerly climate refugia for this species.