Published in HBW Volume 14 on page 185.
Original HBW caption:
Black Drongos are often found accompanying livestock, the object being to capture insects displaced by them, or attracted by them. The same association has been reported in Pakistan for the Ashy Drongo (Dicrurus leucophaeus). These two drongo species will occasionally perch on the animals as they move, and in Sri Lanka, Black Drongos have been observed to eat ticks (Ixodoidea) directly from the backs of mammals. Black Drongos also join parties of Yellow-billed (Turdoides affinis) and Jungle Babblers (T. striata), and Jungle (Acridotheres fuscus) and Common Mynas (A. tristis), hawking insects flushed by these near-ground foragers, and in exchange, providing warning of predators. The Black Drongo is a bird of open country and farmland, rarely entering closed tree cover during the daytime, and often foraging far from any trees. It perches on wires, fence posts, bare treetops, earth banks or other vantage points, sallying to catch prey on the wing or among the leaves, or to snatch insects from the ground. Large items, such as locusts or cicadas, are held down with one foot and progressively torn to pieces with the bill. The wings are generally removed before the prey is swallowed. One Black Drongo, observed while eating a large locust, first made a small jump, while still holding its prey, in order to detach one leg, which it then tore up and swallowed. It repeated the operation with the other legs, and finally removed the head and, after some mastication, swallowed what remained of the body. Black Drongos will also follow human farm workers, pouncing on invertebrates disturbed or exposed by the plough. They are regularly reported pirating worms and other prey from Hoopoes (Upupa epops), mynas and wagtails (Motacilla).