Diet of the Australian Hobby Falco longipennis breeding in Canberra, Australian Capital Territory, in 2002–2004 and 2005–2008

Abstract

The diet of the Australian Hobby Falco longipennis was studied in Canberra (ACT), in the summers of 2002–2003 to 2004–2005 and 2005–2006 to 2008–2009 by analysis of prey remains and pellets (28 and 40 collections for a total of 229 and 132 prey items from six and four nests, respectively). The Hobbies’ breeding diet in the first period consisted of 73% birds, 1% microbats and 26% insects by number, and 98% birds, <1% microbats and 1% insects by biomass, mainly parrots (Psittaculidae), Common Starlings Sturnus vulgaris and sparrows Passer sp. In the second period, it consisted of 94% birds, 3% mammals (mostly microbats), 2% lizards and <1% insects by number, and was more dominated by Starlings and other introduced birds, with the change perhaps reflecting a recent decline in local insect abundance. The Hobby’s dietary metrics correspondingly shifted to a greater Geometric Mean Prey Weight and narrower food niche. The Hobby’s diet overlapped moderately (42%) with that of the similarly sized Collared Sparrowhawk Accipiter cirrocephalus in the ACT over the same timeframe, although the two are separated by foraging habitats and methods.