Group size but not distance to cover influences agile wallaby (Macropus agilis) time allocation

Abstract

Despite their widespread distribution and relative abundance, little is known about the antipredator behavior of agile wallabies (Macropus agilis). The ability to modify time allocation as a function of group size is an antipredator behavior that has been reported in some, but not all, previous studies of members of the genus Macropus. We studied group-size effects and space use for agile wallabies foraging in the open to develop a better understanding of behavior of mid-sized macropods. We found that agile wallabies modified time allocated to foraging and vigilance as a function of group size but were insensitive to distance from cover. We contrast the group size results from agile wallabies with those from other macropodids and speculate that predation by saltwater crocodiles (Crocodylus porosus) may have a profound effect on how agile wallabies perceive and manage predation risk.