Wedge-tailed Eagle Aquila audax Predation on Endangered Mammals and Rabbits at Shark Bay, Western Australia

Abstract

The diet of Wedge-tailed Eagles Aquila audax was assessed from a single nest on Bernier Island and two nests on Heirisson Prong at Shark Bay, Western Australia. The nests and their immediate surrounds were searched for mammalian skulls and the numbers of each species recorded. The nest at Bernier Island was examined annually between July 1992 and October 1995 and the two nests on eirisson Prong in October 1995. Banded Hare-wallabies were the most abundant prey item found in the Bernier Island nest over the four year period comprising 53.0% of all skulls, followed by Rufous Hare-wallabies at 35.9%, Burrowing Bettongs at 8.5% and fish at 2.6%. On Heirisson Prong, one bettong skull and 91 rabbit skulls were collected. Wedge-tailed Eagles displayed a preference for larger prey items on both Bernier Island and Heirisson Prong. They are diurnal predators but on Bernier Island their prey species are largely nocturnal. Possible hunting techniques are discussed.