Drongos are 20 species of handsome birds that make up the family of perching birds known as Dicruridae. Drongos occur in Africa, southern and southeastern Asia, and Australasia. Their usual habitats are open forests, savannas, and some types of cultivated areas with trees.
Drongos are typically black colored with a beautiful, greenish or purplish iridescence. The wings of these elegant, jay-sized birds are relatively long and pointed, and the tail is deeply forked. The tail of some species is very long, with the outer feathers developing extremely long filaments with a "racket" at the end. The beak is stout and somewhat hooked, and is surrounded by short, stiff feathers known as rictal bristles, a common feature on many fly-catching birds other than drongos. The sexes are identical in color and size.
Drongos are excellent and maneuverable fliers, though not over long distances. They commonly feed by catching insects in flight, having discovered their prey from an exposed, aerial perch. Some species follow large mammals or monkeys, feeding on insects that are disturbed as these heavier animals move about.
Drongos sing melodiously to proclaim their territory, often imitating the songs of other species. They are aggressive in the defense of their territory against other drongos as well as potential predators. Some other small birds deliberately nest close to drongos because of the relative protection that is afforded against crows, hawks, and other predators.
Drongos lay three to four eggs in a cup-shaped nest located in the fork of a branch. The eggs are mostly incubated by the female, but both sexes share in the feeding and caring of the young.
The greater racket-tailed drongo (Dicrurus paradiseus) of India, Malaya, and Borneo has a very long tail, which is about twice the length of the body of the bird. More than one-half of the length of the tail is made up of the extended, wire-like shafts of the outer-two tail feathers, which end in an expanded, barbed surface—the racket. These seemingly ungainly tail-feathers flutter gracefully as these birds fly, but do not seem to unduly interfere with their maneuverability when hunting flying insects. The greater racket-tailed drongo is also famous for its superb mimicry of the songs of other species of birds.
Another well-known species is the king-crow (Dicrurus macrocercus) of India, so-named because of its aggressive dominance of any crows that venture too closely, and of other potential predators as well. Like other drongos, however, the king-crow is not a bully—it only chases away birds that are potentially dangerous.
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