Pasting Behaviour Suggests Cryptic Sociality in the Striped Hyaena, Hyaena hyaena

Abstract

Social evolution in the order Carnivora may be investigated through comparative studies of behaviourally diverse extant carnivores. The family Hyaenidae serves as a useful model in such interspecies comparisons, as its member species display various degrees of sociality. However, the behaviour of one of the hyaenids, the striped hyaena, Hyaena hyaena, is poorly understood. Further research into its social ecology will enhance the utility of the family Hyaenidae in elucidating the origins of sociality in carnivores. This research is also critical in conserving this rare and globally declining species. To better understand social behaviour in striped hyaenas, we examined chemical signaling in a population of striped hyaenas in southern Kenya. Although often overlooked in behavioural studies, chemical communication plays a central role in the sensory world of many carnivores, including hyaenids. We tested three non-mutually exclusive hypotheses about the function of “pasting,” a scent-marking behaviour unique to hyaenids, in striped hyaenas. We found that pasting did not function to control food or den resources. We found no evidence that females pasted to demarcate territories. Females pasted at higher rates where their home ranges overlapped with multiple conspecific home ranges; that is, females deposited paste where it was most likely to be detected by multiple conspecifics, suggesting that pasting plays a role in self advertisement. We have yet to find evidence of territoriality among females in this population, leading us to believe that this population may exhibit emergent social tolerance, highlighting its potential utility in studies of social evolution in the order Carnivora.