Plethodontid salamanders are the most diverse group of amphibians in North America and there are over 30 species found in the Southern Appalachians alone. However, these amphibians are vulnerable to anthropogenic climate change and habitat alteration because of their lungless anatomy, requiring respiration to occur through their skin. For such ‘skin-breathing’ to occur, plethodontids must live in cool and moist habitats, making any change in that habitat potentially catastrophic to their survival. While these salamanders are found across most elevations of Southern Appalachians, they inhabit specific microhabitats across the landscape to meet their physiological requirements.
My research centers on understanding how fine-scale abiotic gradients, namely temperature and moisture, drive the distribution, abundance, and demography of salamanders. We have found that salamanders have variable distribution and abundance across a montane landscape whereby at low elevations, where regional climates tend to be warm and dry, salamanders are restricted to stream-side habitats which offer cooler and wetter habitats. At higher elevations, where the regional climate is cool and moist, salamanders are less restricted to streams, and are more uniformly distributed across the landscape. I am pursuing numerous other questions using the foundational knowledge of these spatial patterns. For example, I have an ongoing Mark-Recapture study to determine whether life history and demography vary along temperature and moisture gradients and have conducted experiments to asses variation in stress physiology in response to various abiotic conditions (see Physiology page).
Thermal Image Analyses
Plethodontid salamanders have incredibly small home ranges and low vagility, often living their entire lives in a single 3 square meters. Thus the 'landscapes' salamanders interact with are much smaller than what we traditionally think of with 'landscapes'. Further, salamanders are very sensitive to thermal and hydric conditions at fine-scales. We have been using thermal images to capture the fine-scale thermal and hydric landscapes of the Eastern Red-backed salamander (Plethodon cinereus) and characterizing them using traditional landscape metrics. We are interested in understanding to what extent salamanders select from their available thermal habitat, how this might change across space and time, and the relationships between thermal metrics and physiological and demographic rates. I have been working on this project in collaboration with Dr. Eric Gangloff at Ohio Wesleyan University.