Behavior of the Evening Bat Nycticeius humeralis at a Nursery Roost

Abstract
Roosting behavior was investigated in the evening bat N. humeralis during the summer of 1971 in northern Missouri [USA]. Adult females arrived at maternity colonies by early May. They gave birth by mid-June and had all begun their southern migration by mid-Sept. Females nursed their own offspring during the first 2 wk subsequent to birth; then they nursed any approaching young until weaning. Weaning and foraging flights by the young occurred simultaneously. Adults were found at higher temperatures during lactation than during pregnancy or postlactation. Following weaning, juveniles were found at higher temperatures than postlactating adults. Movement patterns appear to be related to thermoregulation and to water conservation.