Elevated rates of predation on artificial nests in linear strips of habitat

Artificial nests monitored with automatically triggered cameras were used t o determine the intensity of nest predation and the identity of nest predat ors in linear remnants and large remnants of woodland in the wheatbelt of N ew South Wales, Australia. Nests were constructed from wire, grass, and bar k to mimic those of the Red-capped Robin (Petroica goodenovii) and were sto cked with eggs made from modelling clay. The incidence of predation was sig nificantly higher in linear remnants (62% predation) than in large remnants (34%). Forty-seven independent photographic events were recorded, and nine species of bird accounted for all predation. Two species of predator, the Grey Shrike-thrush (Colluricincla harmonica) and the Grey Butcherbird (Crac ticus torquatus), were responsible for 70% of predation and were detected a t nests in both linear and large remnants. The remaining seven species of p redator were detected only at nests in linear remnants. Bird surveys conduc ted in the same sites revealed that of the species of predator identified f rom photographs all, with two exceptions, were present in both linear remna nts and large remnants. However, the abundance of identified predators was significantly higher in linear remnants. This study suggests that linear st rips of vegetation, despite providing habitat in which birds can live, or a conduit through which they can move, may have limited value as breeding ha bitat. The current enthusiasm for protection and creation of corridors shou ld not be at the expense of restoration and sympathetic management of large areas of native vegetation.