Implications of the thermal environment for terrestrial wildlife management

How organisms respond to and are influenced by temperature is one of the most fundamental aspects of ecology. Temperature affects animal physiology, behavior, survival, and reproduction. At broader spatial and temporal scales, temperature affects animal distributions, speciation, and evolution. Although entire textbooks have been devoted to how temperature is related to various aspects of basic animal ecology, applied ecologists have only recently begun to address thermal ecology in wildlife research. New investigations of thermal conditions relative to specific wildlife species have generally found tremendous variation within landscapes. Consequently, multiple species have been shown to respond in predictive ways to thermal variation. Variation in temperature can be due to both topoedaphic features inherent in the landscape as well as differences in vegetation structure and composition resulting from management actions. Although consideration of the thermal environment has received consideration for exothermic species, new evidence indicates that it has major implications to endotherms and may become even more critical under novel climate conditions. Rarely does management consider thermal cover explicitly or in a spatiotemporally dynamic way; in our view, this is a major short-coming of current conservation planning and management actions. We argue that thermal environments should be foundational in the understanding of the habitat concept. Furthermore, restoration and management efforts should specifically consider thermal refuge and pinch points—the discrete time or event when thermal conditions experienced by an organism deviate to extreme values relative to average conditions and limit vital rates and space use of that organism. We suggest that future research on thermal environments work at scales relevant to organisms so that management can adequately address the full extent of a species’ habitat.