Black-shouldered kite, Black-winged Kite

Description:

The black-winged kite (Elanus caeruleus), also known as the black-shouldered kite (not to be confused with the closely related Australian species with the same name), is a small diurnal bird of prey in the family Accipitridae best known for its habit of hovering over open grasslands in the manner of the much smaller kestrels. This Palearctic and Afrotropical species was sometimes combined with the Australian black-shouldered kite (Elanus axillaris) and the white-tailed kite (Elanus leucurus) of North and South America which together form a superspecies. This kite is distinctive, with long wings; white, grey and black plumage; and owl-like forward-facing eyes with red irises. The owl-like behaviour is even more pronounced in the letter-winged kite (Elanus scriptus), a nocturnal relative in Australia. Although mainly seen on plains, they are sometimes seen on grassy slopes of hills in the higher elevation regions of Asia. They are not migratory, but show nomadism in response to weather and food availability. They are well adapted to utilize periodic upsurges in rodent populations and can raise multiple broods in a single year unlike most birds of prey. Populations in southern Europe have grown in response to human activities, particularly agriculture and livestock rearing. This long-winged raptor is predominantly grey or white with black shoulder patches, wing tips and eye stripe. The long falcon-like wings extend beyond the tail when the bird is perched. In flight, the short and square tail is visible and it is not forked as in the typical kites of the genus Milvus. When perched, often on roadside wires, it often adjusts its wings and jerks its tail up and down as if to balance itself. The sexes are alike in plumage. Their large forward-facing eyes placed under a bony shelf that shades them is distinctive; their velvety plumage and zygodactyl feet are characters shared with owls and the genus has been considered as a basal group within the Accipitridae. They are thought to have been adapted for living in savanna habitats where seasonal rodent population peaks occur. Such food resources are also favoured by the owls. The inner vanes of the feathers have velvety barbules. They have a diploid chromosome number of 68 (some older studies claimed 64 for E.c.caeruleus and 66 for E.c.vociferus) with a distinct karyotype with resemblances to the kites and honey buzzards and suggesting a basal position within the diurnal birds of prey

Habitat:

Udawalawe National Park. The national park was created to provide a sanctuary for wild animals displaced by the construction of the Udawalawe Reservoir on the Walawe River, as well as to protect the catchment of the reservoir. The reserve covers 30,821 hectares (119.00 sq mi) of land area and was established on 30 June 1972. Udawalawe is an important habitat for water birds and Sri Lankan elephants. Udawalawe lies on the boundary of Sri Lanka's wet and dry zones. Plains dominate the topography, though there are also some mountainous areas. The Kalthota Range and Diyawini Falls are in the north of the park and the outcrops of Bambaragala and Reminikotha lie within it. The park has an annual rainfall of 1,500 millimetres (59 in), most of which falls during the months of October to January and March to May. The average annual temperature is about 27–28 °C (81–82 °F), while relative humidity varies from 70% to 83%. Well-drained reddish-brown soil is the predominant soil type, with poorly drained low humic grey soils found in the valley bottoms. Mainly alluvial soils form the beds of water courses. The habitat surrounding at the reservoir includes marshes, the Walawe river and its tributaries, forests and grasslands. Dead trees standing in the reservoir are visual reminders of the extent of forest cover before the construction of the Udawalawe Dam. Areas of open grassland are abundant as a result of former chena farming practices.