Meeting Abstract
73.1 Wednesday, Jan. 6 Unraveling the mystery of koala vocalisations: acoustic sensor network and GPS technology reveals males bellow to serenade females. ELLIS, WA*; FITZGIBBON, SI; ROE, P; BERCOVITCH, FB; WILSON, R; University of Queensland, Australia; University of Queensland, Australia; Queensland University of Technology, Australia; San Diego Zoo’s Institute for Conservation Research, CA; University of Queensland, Australia w.ellis@uq.edu.au
How animals respond to the vocalizations of conspecifics can provide insights into both the context and content of their acoustic communication. In this way, responsive behaviors can act as biological translators of animal vocalizations. Little is known about the content or biological function of the vocalizations made by koalas, due to their solitary, cryptic and nocturnal behavior. The spatio-temporal and social arrangement of koalas has been the subject of much conjecture, but the acoustic structure and seasonality of natural calls have been poorly described. We constructed a novel acoustic sensor network using cell phone technology and successfully applied this to monitor the vocal behaviour of free-ranging koalas in central Queensland. We paired these recordings with simultaneously acquired location data from collar-mounted GPS units to examine the relationship between their vocal communication and spatial arrangement. We found clear seasonal variations in bellow dynamics that were associated with environmental conditions, indicating a role for koala bellowing as a cue for mating in this species. Male travel distance was unaffected by season, but females travelled more during the breeding season than at other times of the year. Daily travel and bellows were concentrated around midnight and female, but not male, travel distance during the breeding season was positively correlated with bellow occurrence. We conclude that male bellowing may be mediated by seasonal environmental conditions and represents a probable trigger for oestrus in females, which may respond to the dynamics of male vocalisations in order to select a mate.
