Meeting Abstract
With rising temperatures due to climate change, we expect shifts in the geographic range of many species. Among the species most affected by these dramatic changes in temperatures are the lungless salamanders (family Plethodontidae). Because plethodontids are ectotherms, have permeable skin, are lungless and therefore need cold and wet temperatures to receive oxygen, we expect rising temperatures to cause a reduction in suitable habitat. Individuals that can tolerate a broader range of temperatures should be more successful when experiencing drastic changes in climate. To better understand species’ response to climate change, we determined thermal limits in two species with expansive, but varying geographic ranges: the Eastern red-backed salamander (Plethodon cinereus), and the northern slimy salamander (Plethodon glutinosus). Additionally, we measured CT limits for both species at high and low elevations to account for geographic variation in thermal physiology. After acclimating all individuals to a similar temperature for 7-10 days, we measured critical thermal minimum (CTmin), critical thermal maximum (CTmax), and calculated thermal breadth (CTmax – CTmin). We found that P. glutinosus has a broader thermal breadth than P. cinereus, and that CTmin and CTmax generally decreased with elevation. CTmax was higher for P. glutinosus, whereas CTmin depends on species and elevation. Based only on their CT limits, we expect P. glutinosus to tolerate a wider range of temperatures and, therefore, be more resilient to climate change. Quantifying species’ thermal limits will enhance our predictions of geographic range shifts in response to climate change.
