Hibernation of the Big Brown Bat

Abstract

Relatively few of the some 1300 species of bats live in the temperate regions of the world. Many of the species found in this northern region live through the winter by hibernating. But hibernating bats, in contrast to other hibernating mammals such as the hedgehog and ground squirrels, are essentially poikilothermous (Kayser, 1940). Their metabolism is proportional to their body temperature, and in the inactive state they show no evidence of a thermoregulatory mechanism (Hock, 1951). Hence in bats there appears to be no real distinction between sleep and hibernation. The state of hibernation for bats can be defined, then, only as a relatively long period or series of periods when the animals are subjected to low environmental temperatures, become inactive, and have a very low metabolic rate correlated with a low body temperature.