The grey goshawk the white morph of which is known as the white goshawk, is a strongly built, medium-sized bird of prey in the family Accipitridae.
Description
The grey morph has a pale grey head and back, dark wingtips, barred grey breast and tail, and white underparts. The white morph is the only bird of prey in the world to be entirely white, although there is the Gyr falcon and Siberian goshawks which are white. Grey goshawks are the largest Accipiters on mainland Australia, at about long, with wingspans of. Females are much larger than males, weighing about on average while males average. The population on the Solomon islands is much smaller however, with a female found to have weighed and two males averaging.
Distribution and habitat
The grey goshawk is found along the coasts of northern, eastern and south-eastern Australia, Tasmania and rarely Western Australia. The variable goshawk was previously considered a subspecies. Their preferred habitats are forests, tall woodlands, and timbered watercourses.
Grey goshawks often seem to vary their prey selection opportunistically. For an Accipiter, they relatively often select mammals such as rabbits, possums, and bats. Other prey can include small reptiles, and insects. However, the most frequent prey type are most often birds. Evidence from different parts of the range shows females select larger prey than males, with males largely keeping to small to mid-sized passerines while females often prey on larger prey such as currawongs, gamebirds and even herons. Pigeons and parrots are a popular prey item for grey goshawks. Evidence indicates that this species is less agile in the air and less skilled at twisting pursuits over the ground than co-occurring brown goshawks but, on the other hand, the grey species is more powerful and so select typically larger prey. Hunting is often done by stealth, but grey goshawks are willing to pursue their prey before catching it with their talons.
Breeding
Grey and white goshawks interbreed freely. They partner for life, breeding from July to December. They nest in tall trees on a platform of sticks and twigs with a central depression lined with green leaves. The female lays a clutch containing 2 or 3 eggs, which are incubated for about 35 days. Chicks fledge 35–40 days after hatching. The female is usually responsible for incubating the eggs and feeding the young. The male does most of the hunting.
