Christman, T.M.*; Finkler, M.S.: Overwintering Energetics of the Red-backed Salamander, Plethodon cinereus.
Red-backed salamanders are known to actively forage during the winter. The present study examined the importance of successful foraging to the overall energy budget during overwintering. We measured oxygen consumption rate and whole-body triglyceride and glycogen contents before and after a five-month overwintering period in salamanders that were either unfed or fed 5 fruit flies 3x per week. Oxygen consumption increased markedly over the course of overwintering, with a nearly two-fold increase in fed animals. Unfed animals initially had greater rates of oxygen consumptio than did fed animals, but this difference disappeared by the end of overwintering. The triglyceride and glycogen contents of fed animals at the end of overwintering did not differ from those at the beginning of overwintering, whereas both values decreased significantly in unfed animals. Though preliminary, the data suggest that winter foraging may be an important component of the energy budgets of P. cinereus. Moreover, the data highlight changes in metabolic rate during the course of overwintering that may need consideration in estimates of overwintering energy budgets.