Physical characteristics

Resembling stream-lined, long-tailed starlings, drongos are a picture in black—black in plumage, bill, and feet—except for the gray ashy drongo (D. leucophaeus) in Southeast Asia; immatures are duller and sootier, and in some species faintly scalloped, barred, or spotted paler. Eyes, brilliant red in most species (though whitish or brown in some forms), provide the only color contrast; immatures are brown-eyed without exception. Plumage is extensively glossed in green, blue, or purplish sheens, the gloss sometimes spangling hackles on head and breast. Some species are also crested. Crests vary, according to species, from a short tuft of erect feathers on the forehead to bare hair-like plumes or a mane of broadened curled feathers curving back over the head.

Bills are stout, deep, and rather aquiline, well-notched for grasping prey, and clothed with dense, forward-directed bristles at the base. The bristles, which hide slit-like nostrils, are thought to protect the face from retaliation by captured prey; in Chaetorhynchus they extend to the bill tip. Feet are short but

Black drongo (Dicrurus macrocercus) chicks at their nest. (Photo by T.D. Singh/VIREO. Reproduced by permission.)

strong, and with the toes about as long as the scutellate "leg," are better fitted for perching than movement. Adapted for aerial maneuvers, wings are rather long and pointed, with 10 primaries (tenth well-developed) and nine secondaries plus a remicle. It is the tail that sets drongos apart from other songbirds. Sometimes square-tipped but usually long and forked, it comprises 12 feathers in Chaetorhynchus and only 10 in Dicrurus, and is often diversely modified by a great lengthening and curling of the outermost pair of feathers. In two species, these plumes are largely bare of webbing except for spatula-like tips; but the function of such modification is not clear. Tails in all species are at least as long as the body, and up to three times as long, even more, in some. Because of this, drongos vary enormously in length, from 7 in to over 23.5 in (18-60 cm).

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