Monday, March 19, 2012

>Accipiter trivirgatus (Crested Goshawk)

Crested Goshawk


Crested Goshawk
Adult male
Conservation status
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Aves
Order:Falconiformes (but see there)
Family:Accipitridae
Genus:Accipiter
Species:A. trivirgatus
Binomial name
Accipiter trivirgatus
(Temminck, 1824)
The Crested Goshawk (Accipiter trivirgatus) is a bird of prey from tropical Asia. It is related to other diurnal raptors such as eaglesbuzzards (or buteos) and harriers, and thus placed in thefamily Accipitridae.

Adults are plain dark grey-brown above. Note the crest.

Description

This raptor has short broad wings and a long tail, bothadaptations to manoeuvring through trees. It is 30–46 cm in length, with the female much larger than the male. The larger size and a short crest, clearly visible in profile, are the best distinctions from its relative, theBesra (A. virgatus).
The male has a dark brown crown, grey head sides and black moustachial and throat stripes. The pale underparts are patterned with rufous streaks on the breast and bars on the belly. The larger female has a browner head and brown underpart streaks and bars. The juvenile has pale fringes to its head feathers, and the underpart background colour is buff rather than white.
The flight is a characteristic "slow flap, slow flap, straight glide", similar to other Accipiter species such as the Northern Goshawk (A. gentilis).

Range and ecology

The Crested Goshawk breeds in southern Asia, from India and Sri Lanka to southern China,Indonesia and the Philippines. It is primarily a lowland bird, and an all-year resident. Even in uplandhabitat it is resident in winter, for example in the Himalayas foothills of Bhutan or in Sal (Shorea robusta) forest in India's Dehradun district. In these lands at the northern end of its range, it is generally very rare however. Essentially it is limited to tropical and warm subtropical areas.
Like its relatives, this secretive forest bird hunts birds, mammals and reptiles in woodland, relying on surprise as it flies from a perch to catch its prey unaware. It builds a stick nest in a tree and lays two or three eggs.
The ischnoceran louse Degeeriella storeri is a parasite of this bird; it is not yet known from any other host species. On the other hand, Kurodaia fulvofasciata, an amblyceran louse parasitizing the Crested Goshawk, is widely found on birds of prey throughout the Holarctic.
In Hong KongA. trivirgatus is a protected species under Wild Animals Protection Ordinance Cap 170. It can be found in Kam Shan Country Park.

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