Thursday, April 10, 2008

Black Drongo

Black Drongo (Dicrurus macrocercus) is a small Asian bird. The drongos are passerines restricted to the Old World tropics. They were previously classed as the family Dicruridae, but that has been much enlarged to include a number of largely Australasian groups, such as the Australasian fantails and the monarchs and paradise flycatchers.
The Black Drongo is a common resident breeder in much of tropical southern Asia from southwest Iran through India and Sri Lanka east to southern China and Indonesia.
This species is usually found in open forests and similar lightly wooded habitats, including farmland and habitation. Three or four eggs are laid in a light cup nest placed in a fork often on the bare outer branches of trees.
These are aggressive and fearless birds, 28 cm in length, and will attack much larger species if their nest or young are threatened. There are also some cases of Drongos preying on small birds. They have also been on occasion seen feeding on dead fish.
The adult Black Drongo is mainly glossy blue-black, although the wings are duller. The tail is long and deeply forked, and there is a white spot in front of the eye. Young birds are dull dark brown.The Black Drongo has short legs and sits very upright whilst perched prominently, like a shrike. It eats insects and other small animals.
Description: The Spangled Drongo measures 28cm - 33cm. It has glossy black plumage, with iridescent blue-green spots (spangles) and blood red eyes. Sexes are similar, but the female is slightly smaller. Occasional white spotting can be seen on the upper wings of both sexes. The long, forked 'fish' tail is characteristic, and distinguishes the Spangled Drongo from other similar-sized black birds. Young birds are more sooty black without the spangles and the eye is brown.
The Spangled Drongo is noisy and conspicuous, usually active, and frequently aggressive to other species. The voice comprises a variety of sounds, including some distinctive metallic notes like a stretched wire being plucked, and occasional mimicry of other bird species.
Several other species are glossy black with red eyes. The Metallic Starling, Aplonis metallica, (21cm - 24cm) is found on the north-east coast, and has black plumage, brightly glossed with green and purple, a bright red eye and long tapered tail. The Trumpet Manucode, Manucodia keraundrenii, (28cm - 32cm) is restricted to northern Cape York Peninsula; it has slender plumes on the nape and throat. The adult male Common Koel, Eudynamys scolopacea, (40-46 cm) is larger and lacks the spangles and fish tail.
Distribution and Habitat: Spangled Drongos are found throughout northern and eastern Australia. They prefer the wetter forests, but can also be found in other woodlands, mangroves and parks. Birds tend to avoid more dense forest types and rainforest interiors. Birds are more common in the north, and are often seen either singly or in pairs.
Through its range, the Spangled Drongo shows different migratory habits. Northern populations tend to be more migratory than southern ones. The movements are somewhat mysterious. Individuals from the northern areas of Western Australia and the Northern Territory migrate northwards to Indonesia, while the eastern Australian birds migrate to New Guinea. Some drongos in the south-east and central-east, however, remain in the same area or head south, occasionally turning up in Tasmania.
The species is also found in New Guinea and eastern Indonesia. Closely related species occur through south-east Asia to India, China, and the Philippines and on some south-west Pacific islands.
Food and Feeding: The Spangled Drongo is usually observed perched on an open branch or telegraph wire, where it awaits a passing insect. Once seen, its prey is pursued in an acrobatic display, and is caught in the drongos slightly hooked bill. The Spangled Drongo then returns to its perch to eat its victim. The prey is guided into the bill with the assistance of sensitive, long, wire-like rictal bristles bordering the bill. Insects are also taken from foliage and from under bark; fruit and nectar also form part of its diet.
Breeding: Spangled Drongos breed from September to March, and normally have only one clutch per season. Both adults participate in building the nest, which is a simple, shallow cup of twigs, vine tendrils and grasses, held together with spider web. It is placed in a horizontal fork of tree, normally toward outer edges and up to 10m - 20m above the ground. Both sexes incubate the three to five eggs and care for the young. Spangled Drongos actively defend the nest against intruders.

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