A comparison of the diets of the Black-shouldered Kite 'Elanus axillaris' and Nankeen Kestrel 'Falco cenchroides' in the Canberra region

Abstract

We compare for the first time the diets of sympatric populations of the Black-shouldered Kite 'Elanus axillaris' and Nankeen Kestrel 'Falco cenchroides' in the Australian Capital Territory (ACT). Diets of the two species were documented by collecting prey remains (pellets, orts and remains) from nest sites between December 2002 and July 2008. The kite's diet comprised mostly small mammals (93% by mass); the kestrel consumed mainly invertebrates (86.1% by number), as well as some mammals, birds and reptiles (collectively 94.8% by mass). We discuss the observed limited dietary overlap, and possible factors that enable the two species to coexist in the ACT.