Factors Affecting the Resting and Postflight Body Temperature of Little Brown Bats, Myotis lucifugus

Abstract

The body temperature ( ) of freshly captured, adult female little brown bats (Myotis lucifugus) was investigated using two ambient temperature ( ) regimes. Exposure began with 12 C at 0600 hours and were gradually raised to either 22 or 32 C. Body temperatures were measured at 1600 hours. In general, lactating females did not attain as high a as did pregnant or postlactating bats. Bats caged in clusters of seven to 12 animals had significantly greater than bats caged singly. Seasonal acclimatization over the 3-mo reproductive period was evident at the lower test . The of M. lucifugus appeared to be a facultative and graded response to recent environmental conditions and the effect of those conditions on the foraging success of the bats. The of bats immediately after foraging flights was strongly correlated with , but feeding period (first or second), date, cloud cover, and age (adult vs. juvenile) also explained some of the variation in postflight .