Meeting Abstract
Understanding the proximate factors that limit species geographic distributions is a fundamental aspect of ecology. Ecological niche modeling (ENM) is a tool that is used with increasing frequency to aid in understanding species distributions and conservation planning. Both survival and reproduction are essential for species’ persistence, but the set of environmental conditions that support each of these components may not be the same. In this study we used ENM to examine the climate envelope of the alligator snapping turtle and assess potentially limiting environmental variables on the distribution of this species. We also incorporated incubation temperature requirements with our modeled distributions to determine if embryonic development constrains the species’ northern limits. We discuss our results with respect to conservation management practices aimed at restoring this species at the northern edge of the species’ range. We found that low annual precipitation likely constrains the western distribution of alligator snapping turtles while the northern distribution is likely constrained by thermal requirements during incubation. Only a portion of the range predicted to have a high probability of suitability for survival was estimated to be capable of supporting successful embryonic development. If historic occurrence records are accurate, adult alligator snapping turtles appear to be able to survive colder climes than they would be able to consistently and successfully produce offspring in. Our study highlights the importance of considering survival and reproduction when estimating species’ ecological niches as well as the benefits of incorporating physiological data when evaluating species distributions.
