Thursday, March 8, 2012

>Aquila hastata (Indian Spotted Eagle)

Indian Spotted Eagle


Indian Spotted Eagle
Adult
Note wide mouth and dark eyes
Conservation status
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Aves
Order:Falconiformes
(or Accipitriformes, q.v.)
Family:Accipitridae
Subfamily:Buteoninae (disputed)
Genus:Aquila
Species:A. hastata
Binomial name
Aquila hastata
(Lesson, 1834)
Range of A. hastata in dark green
The Indian Spotted Eagle (Aquila hastata) is a large South Asian bird of prey. Like all typicaleagles, it belongs to the family Accipitridae. The typical eagles are often united with the buteossea eagles and other more heavyset Accipitridae, but more recently it appears as if they are less distinct from the more slender accipitrine hawks.

Description

The Indian Spotted Eagle is a stocky, mid-sized eagle at about 60 cm in length and has a wingspan of 150 cm. It is broad-headed, with the widest mouth of all spotted eagles. This species has a lighter coloration overall compared to its relatives, with a darker iris that makes the eyes appear darker than the plumage (rather than the other way around as in the northern spotted eagles). Adults can be told apart from the Greater Spotted Eagle by its lighter color, darker eyes, and habitat preferences (see below). After about three or four months the young birds are glossy brown with the tips of the head and neck feathers being creamy and giving a spotted appearance. The upper tail coverts are light brown with white giving a barred appearance. The median coverts have large creamy spots. After about eighteen months the bird moults and becomes a darker shade and has less spots. Some older juveniles, unlike the Lesser and Greater species, are not strongly spotted at all, making the common name somewhat misleading, and also lack the creamy buff nape patch of the juvenile Lesser Spotted Eagle.

Distribution and habitat

The Indian Spotted Eagle is native in BangladeshIndiaMyanmar and Nepal, where it prefers subtropical and tropical dry forests to plantations and arable land. It is vagrant in Pakistan. In Nepal, it is resident and breeding in Chitwan and Bardia National Parks, in Sukla Phanta and Koshi Tappu Wildlife Reserves and in some unprotected areas in the Terai.In India, it is distributed sparingly over the Gangetic plains, in the east up to Manipur, in Madhya Pradesh and southernOrissa, but in the south limited to Kotagiri and MudumalaiNilgiris districtTamil Nadu andTumakuruKarnataka.
This species can often be approached quite closely for a large raptor. Unlike the Greater Spotted Eagle, which is a winter visitor to Indian wetlands, this species does not show any special affinity for wetland habitats.

Systematics, taxonomy and evolution


Illustration of an adult and a juvenile byJoseph Smit (1875)
The Indian Spotted Eagle was earlier considered as the resident of eastern subspecies of the Lesser Spotted Eagle but has proven quite distinct and readily separable by morphologicalbehavioralecological and DNA sequence data. The Indian lineage seems to have diverged around the middle Pliocene, perhaps some 3.6 million years ago, from the common ancestor of the Lesser and Greater Spotted Eagles. The "proto-Spotted Eagle" probably lived in the general region of Afghanistan, being split into a northern and a southern lineage when both glaciers and deserts advanced in Central Asia as the last ice age began.
The spotted eagles as a group are quite distinct from the typical members of Aquila, the "true eagles". They will probably be separated in LophaetusIctinaetus or a genus of their own in the near future.

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