Observational studies of the effects of warming on vertebrate ectotherm populations have produced contradictory findings. Our study leverages an ongoing soil warming experiment and an abundant salamander with a small home range to achieve three research objectives: 1) Determine the effects of soil warming on salamander population characteristics such as density and mean body size; 2) Determine the effects of soil warming on the life history of individual salamanders, including summer and winter survival, growth rate, and fecundity; 3) Determine whether salamanders compensate for soil warming by altering their seasonal activity periods, their microhabitat use, or their foraging behavior. By bringing a rigorous experimental approach to these objectives, this project can significantly advance our understanding of how warming will affect populations of vertebrate ectotherms.