Mother–offspring recognition in the bat Carollia perspicillata

Abstract

Parental care is crucial for offspring survival in many taxa but its burden and costs are often not equally distributed between the sexes. In bats, the majority of parental care is provided by females, making examples of paternal support towards pups exceedingly rare. One exception to this general pattern seemed to be the polygynous Seba's short-tailed fruit bat Carollia perspicillata; two earlier studies suggested that paternal care occurs, i.e. that harem males prompt females to retrieve vocalizing pups. To corroborate this suggestion, we investigated the occurrence of maternal and paternal care in reaction to pup isolation calls in C. perspicillata. Acoustic measurements of 905 isolation calls from 17 pups revealed sufficient interindividual variation to encode an individual vocal signature. Correspondingly, mothers were capable of using this individual signature to discriminate between their own pups and age-matched pups from other females belonging to their colony. Maternal experience was positively correlated with the strength of response behaviour during playbacks. Thus, our results indicate that pup isolation calls were used to elicit maternal care and that mothers recognize their pups based on an individual signature in isolation calls. However, in contrast to the previous studies mentioned above, we found no evidence that harem males reacted to pup isolation calls by prompting the respective mothers to retrieve their vocalizing pups. Instead, our results demonstrate that harem males engaged in courtship activities that were unaffected by pup isolation calls.