Grey Goshawk

The grey goshawk (''Accipiter novaehollandiae'') is a strongly built, medium-sized bird of prey in the family ''Accipitridae'' that is found in eastern and northern Australia. The white morph of this species is known as the white goshawk.

Taxonomy

The grey goshawk was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's ''Systema Naturae''. He placed it with the eagles, hawks and relatives in the genus '' Falco'' and coined the binomial name ''Falco novaehollandiae''. Gmelin based his description on the "New Holland white eagle" that had been described in 1781 by the English ornithologist John Latham. Latham in turn had based his short description on information provided by Johann Forster who had accompanied James Cook on his second voyage to the Pacific Ocean. Two specimens had been collected in March 1773 at Adventure Bay in Tasmania. The grey goshawk is now one of 49 species placed in the genus ''Accipiter'' that was introduced in 1760 by the French zoologist Mathurin Jacques Brisson. The genus name is Latin for "hawk", from ''accipere'', "to grasp". The specific epithet ''novaehollandiae'' is Modern Latin for " New Holland", the name given to western Australia by early Dutch explorers. In ornithology the name is used for eastern Australia, especially New South Wales. The grey goshawk has no recognised subspecies.

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.

Grey goshawks are the largest ''Accipiter''s on mainland Australia, at about long, with wingspans of . Females are much larger than males, weighing about on average (and sometimes scaling up to ) while males average .''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), . 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.

Behaviour and ecology

Food and feeding

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 (including megapodes) 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.

Conservation status

State of Victoria (Australia)
* The grey goshawk is listed as threatened on the Victorian Flora and Fauna Guarantee Act 1988

Under this Act, an ''Action Statement'' for the recovery and future management of this species has not been prepare

* On the 2007 advisory list of threatened vertebrate fauna in Victoria, this species is listed as Vulnerable species, vulnerable.

State of Queensland
* This species is listed as least concern in Queensland

Gallery

File:Grey goshawk 1 SF20361 01.jpg, Grey goshawk in Edge Hill, Queensland, Australia
File:Grey goshawk 2 SF20361.jpg, Grey goshawk in Edge Hill, Queensland, Australia
File:Grey Goshawk (Accipiter novaehollandiae) 2370.jpg
File:Grey goshawk 1 (21894521433).jpg
File:(1)Grey goshawk.jpg, Grey goshawk, white morph
White Goshawk.jpg, A white goshawk

References

*Marchant, S.; & Higgins, P.J. (Eds). (1993). ''Handbook of Australian, New Zealand and Antarctic Birds. Vol,2: Raptors to Lapwings''. Oxford University Press: Melbourne.

External links

Rainforest-Australia.com: grey goshawk

{{Taxonbar, from=Q938996

grey goshawk
Birds of prey
Birds of Australia
Birds of Tasmania
Diurnal raptors of Australia
Birds described in 1788
Taxa named by Johann Friedrich Gmelin