The cuscus, Phalanger orientalis, was probably the most important food source in New Ireland from its introduction 20,000 years ago until the introduction of the pig, Sus scrofa, 3500 years ago. Terrestrial, or land-based, fauna were an essential part of the prehistoric diet because they provided both protein and fat, which were often difficult to obtain from marine resources alone. P. orientalis was an important prey species because New Ireland had a relatively low range of prey taxa. Prior to 20,000 B.P., the New Ireland fauna were relatively meager: the potential terrestrial prey taxa for prehistoric hunters included bats, rats, birds, and reptiles. The introduction of the cuscus dramatically increased the number of individual animals and therefore expanded the island-based protein resource available to prehistoric hunters. This paper investigates the nature of the late Pleistocene to Holocene capture of P. orientalis based on data from Buang Merabak, a central New Ireland cave site, and investigates whether prehistoric hunters captured P. orientalis of a particular age and how this changed over time.