The foraging behaviour and ecology of animal-eating bats

Abstract

The results of recent studies of the foraging behaviour of animal-eating bats are considered in this review. The advent of small (< 1 g) radio transmitters has made it possible to collect data on individual variations in foraging behaviour for species with body mass over 15 g. These data can be combined with those from wing morphology and echolocation call design to assess the flexibility achieved by some bats. The information concerning bats can be placed in a broader perspective by considering it in the light of current ideas about foraging theory. In this review, information about bat foraging is considered in the context of structural and functional features, the former relating to bats' access to habitats of different complexity and the latter to their behavioural responses. Mechanical features involving wing morphology and perceptual features, such as the ability of echolocating bats to deal with clutter, combine to influence the behavioural flexibility of individuals. This, in turn, affects access to prey and patterns of community structure. Bats relying on airborne prey appear to be limited to small prey items, whereas those hunting nonairborne targets may take much larger prey. Variation in individual behaviour means that terms such as gleaning, perch hunting, piscivory, and carnivory do not accurately define the foraging of animal-eating bats. Morphological and behavioural data suggest that sympatric animal-eating bats of similar size will show considerable overlap in prey taken and in patterns of habitat use.