Social behavior of the little brown bat, Myotis lucifugus

Abstract

1. As part of an overall study of the social behavior of the little brown bat, Myotis lucifugus, we compiled the vocal repertoire of this gregarious species in its natural habitat. Ten vocalizations were identified and associated with certain behavioral contexts. 2. Echolocation pulses, although primarily used for or entation, are also available as interindividual communication signals and modified forms are used in several situations such as during near-collisions in flight and the first flights of newly volant young. 3. Nonecholocation calls are used in three main contexts. Agonistic vocalizations appear to take the place of physical aggression and may be used to protect an individual's position within a roost. Two vocalizations emitted in maternal-infant situations appear to contain vocal signatures which are important for individual recognition. During mating, a distinct copulation call given by males likely conveys a male's sexual motivation to a female in the absence of precopulatory displays. 4. The size of the vocal repertoire is comparable to those of some solitary mammals. Behavioral observations indicate that despite the gregarious nature of the species, a simple social system exists and the small repertoire is therefore not surprising.