Black drongo

Dicrurus macrocercus taxonomy

Dicrurus macrocercus Vieillot, 1817, "Afrique" = Madras, India. About seven subspecies, differing in size, tone of gloss and wing lining, tail function, and presence of a white facial spot.

other common names

English: King crow; French: Drongo royal; German: Konigs-drongol; Spanish: Drogo Real.

physical characteristics

11-13 in (26-32 cm); 1.5-2.2 oz (40-60 gm). The archetypal drongo, slender bodied, jet black with blue or green gloss, red eye, uncrested and without hackles but well bristled around bill, and tail deeply forked; sexes are similar, and immatures dull, shorter-tailed, and brown-eyed.

distribution

Southeast Iran and south Afghanistan through south Himalayas to all India, Sri Lanka and mainland Southeast Asia north through central and east China to Formosa and south Manchuria, at altitudes from sea level to 6,600 ft (2,000 m); also an outlying population on Java and Bali.

habitat

Savannas, fields, and urban habitats outside forest, in more open environments than occupied by other drongos; over much of its range the black drongo has become a commensal of man.

behavior

Thrives in open habitat, seeking exposed vantage perches in isolated trees, fence posts, tops of banks, buildings, and electric wires and poles, and sallying out from them on wing in buoyant, acrobatic evolutions. Tropical populations are resident but opportunistically nomadic out of breeding, and more temperate populations north through China are strongly migratory. This species is more social than other drongos, particularly out of breeding and may roost in flocks, dispersing at dawn to respective feeding territories. It is also especially pugnacious and fearless in defending feeding and breeding territory from larger, predatorial birds. Calls comprise a variety of harsh metallic chatterings; in apparent courtship, pairs or competitive trios perch close or face to face duetting or counter-singing in harsh scolding notes accompanied by violent up-and-down head-bowing and wing fluttering aerial chases.

feeding ecology and diet

An opportunistic aerial insectivore, congregating loosely at concentrations of food and environmental disturbances that flush it, such as fire, grazing domestic stock, field clearing, and ploughing. Black drongos even chase other birds piratically for captured prey, and will sometimes settle on the ground to pick up ants and emerging termites. Their staple diet comprises a range of large, hard-cased field insects—locusts and crickets, beetles, and bees— and also some moths and butterflies and, infrequently, small reptiles, birds, and bats. Nectar is an important supplement, and the drongos may play a useful role in plant pollination.

reproductive biology

Breeds from February to August, earlier in the tropics and later in more temperate regions, coincident with peaks in insect activity. Nest a flimsy saucer of twigs, grass, and fiber, cemented and bound with cobweb to a horizontal fork at end of a branch about 13-39 ft (4-12 m) above the ground, commonly in an isolated tree with clear view of surroundings. Eggs, in clutches of 2-5, are 0.8-1.1 x 0.7-0.8 in (20-28 x 18-20 mm), whitish to pinkish cream and spotted and blotched with reddish brown and black. Nests are often parasitized by cuckoos, e.g., Surniculus lugubris and Eudynamys scolopacea.

conservation status

Not threatened.

significance to humans None known. ♦

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