Roosting Ecology of Bats

Abstract

Bats spend over half their lives subjected to the selective pressures of their roost environment; thus it is not surprising that the conditions and events associated with roosting have played a prominent role in their ecology and evolution. Roosts provide sites for mating, hibernation, and rearing young; they promote social interactions and the digestion of food; and they offer protection from adverse weather and predators. Conditions that balance natality and mortality and enhance survivorship are intimately linked to roost characteristics and are paramount to the success of a species. The roosting ecology of bats can be viewed as a complex interaction of physiological, behavioral, and morphological adaptations and demographic response. The roosting habits of bats may be influenced by roost abundance and availability, risks of predation, the distribution and abundance of food resources, social organization, and an energy economy imposed by body size and the physical environment. For many bats the availability and physical capacity of roosts can set limits on the number and dispersion of roosting bats, and this in turn can influence the type of social organization and foraging strategy employed. For example, some bats as refuging animals (see Hamilton and Watt, 1970) may benefit from improved metabolic economy and information transfer but may be subjected to the added costs associated with increased commuting time, competition for food, and risks of predation.