Considering management context when investigating behavioral profiles in a group of captive Javan gibbons (Hylobates moloch)

Abstract

Effective animal husbandry aims to produce behavioral profiles consistent with those observed in wild counterparts. However, few studies have examined the impacts of management history on sociality. We investigate social dynamics in a group of Javan gibbons (Hylobates moloch) at Perth Zoo using behavioral and proximity data. The group consists of an aging adult female and her two offspring–a maturing sub-adult female and a juvenile male. This composition diverges from commonly observed groupings in the wild. The study group’s social relationships generally align with species-typical behaviors, with the exception of the patterning of play behavior and resting-in-contact. These results indicate an uncharacteristically close bond between the mother and her maturing same sex-offspring, as well as an unexpectedly distant mother-juvenile bond. These relationships are best explained by the group’s management history and resulting atypical group composition including: the absence of an adult male, the mother’s advanced age, and the hand-rearing of the juvenile male. This study gives insight into the effects of a captive setting on social development and provides further evidence of social flexibility in gibbons.