Breeding Parameters of the Brown Goshawk Accipiter fasciatus in South-eastern Australia

Abstract

Sixty-seven breeding attempts of the Brown Goshawk Accipiter fasciatus were investigated on 26 temtories. Incubation generally commenced in October, although as early as mid-September and as late as early December. Incubation took 30- 35 days, most young hatching in November. The nestling period was usually 28-35 days; males generally fledged earlier than females. No breeding occurred outside the springlsummer period. Nests were placed high in mature Eucalyptus trees in woodland within 200 m of pasture. Nest trees were commonly on sheltered slopes of southerly or easterly aspect. Approximately 30% of nests were beside the trunk of the nest tree, the remainder being in branch forks 1-12 m from the trunk. Active nests were never closer than 1.6 km apart. Breeding density and success declined from 31.3 active nests1100 km², 2.31 young fledgedlactive nest in 1981 to 20.3 active nests1100 km², 1.54 young fledgedlactive nest in 1983. From 50-77% of territories held active nests in any one year during 1981-83. Particular nests were used for several years in succession on some territories, however there was no correlation between nest re-use and prior breeding success. Limited evidence was found for territory fidelity from year-to-year.