The Bioenergetics of Hibernation in the Eastern Garter Snake Thamnophis sirtalis sirtalis

Abstract

Body composition changes during hibernation were measured for garter snakes maintained in a laboratory hibernaculum and snakes from a natural hibernaculum in Wisconsin. Laboratory animals were maintained at 4 C, 24-h darkness (DD), for 165 days, the period of natural hibernation. Twelve randomly selected individuals were assayed at the beginning and end of natural hibernation and for every 6 wk of simulated hibernation. The final laboratory assay was performed concurrently with field emergence. Glycogen and proteins from liver and muscle tissues were utilized by both laboratory and field snakes during hibernation. Muscle catabolism of these substrates accounted for 76.5%-78.7% of the total winter energy budget. No change was observed in total body weight, liver weight, tissue lipid content, fat-body weights, organic matter, inorganics, or water content. The similarity between energy budgets for field (0.45 cal/ g/day) and laboratory (0.42 cal/g/day) hibernating snakes indicates that natural hibernation was closely simulated.