Breeding biology of the speckled warbler, Chthonicola sagittata

Abstract

I studied the breeding biology of the speckled warbler in a large (>1000 ha) remnant of eucalypt woodland in the Australian Capital Territory, monitoring 160 nesting attempts over three breeding seasons. In many aspects of breeding the species is a typical member of the Acanthizinae. It laid a small clutch (usually 3 eggs) with a laying interval of two days, and had long incubation and nestling periods, 17-20 days and 15-19 days respectively. There was biparental care of the altricial young and fledglings were dependent for a long period; fledglings were fed for about 5 weeks and all dispersed about 7 weeks after leaving the nest. Females were multi-brooded, fledging up to 3 broods in a season from a maximum of 6 clutches, but despite this had a low reproductive rate over a long breeding season. Low reproductive success, about 1.0 fledgling per female per season, resulted mainly from nest failure due to predation; all nests were built directly on the ground and were thereby exposed to a wide range of predators and other forms of mishap. The implications of this invariable nesting strategy are discussed for populations nesting in fragmented landscapes in small remnants of habitat. Show more