The Black Drongo (Dicrurus macrocercus) is a small passerine bird from Asia that belongs to the Dicruridae family of drongos. It is a common breeder in a lot of tropical southern Asia, from southwest Iran east through India, Sri Lanka, southern China, and Indonesia. It has also been seen in Japan by accident. It is a black bird with a forked tail that makes it stand out. It is 28 cm (11 in) long. It eats insects and can be found all over its range in open farmland and light forest, perching in plain sight on a bare perch or along power or phone lines.
The species of bird is known for being aggressive toward much bigger birds, like crows, and will dive-bomb any bird of prey that comes into its territory. Because of this, people sometimes call it a “king crow.” Smaller birds often nest near a black drongo nest, which is a safe place to do so. Before, the Asian fork-tailed drongo (Dicrurus adsimilis) was grouped with the African fork-tailed drongo (Dicrurus adsimilis), but now it is seen as a separate species with several different populations.
Black Drongo Bird Species
The black drongo bird has been brought to some islands in the Pacific, where it has done well and become so common that it is threatening and killing off native and endemic bird species. Once, people thought that the black drongo was a subspecies of the fork-tailed drongo (Dicrurus adsimilis), which is a close relative that only recently became its own species. Both are now thought to be different species.
The fork-tailed drongo lives only in Africa, while the black drongo lives in Asia. There are seven subspecies, but most of the populations are close to each other and show clinal variation and intergrade. People from northern India are bigger than people from Sri Lanka, while people from peninsular India (nominate subspecies) are in the middle. Thailand, Hong Kong, and China are all places where race cathoecus lives.
This species has a much smaller spot on the back of its head, and its dark wings have a greenish sheen. A race of thai lives in southern Siam, but it overlaps with cathoecus that come there for the winter. Java and Bali are both home to the Javanese race, Javanus. In the Formosa race harterti, the tail is shorter than the wing. This bird is shiny black, and its tail has a wide fork. At the base of the gape, adults usually have a small white spot.
The dark brown iris (not crimson as in the similar ashy drongo). In the field, you can’t tell the men from the women. The young birds are brown and may have white bars or spots on their bellies and vents. They can be confused with the white-bellied drongo. First-year birds have white tips on their belly feathers, but second-year birds only have white tips on their vent feathers. They are aggressive and fearless birds.
Even though they are only 28 cm (11 in) long, they will attack crows and birds of prey that come into their nesting territory. Because of this, they used to be called “king crows.” They fly with powerful flaps of their wings and can move quickly, which helps them catch flying insects. They sit straight up on thorny bushes, bare perches, or electricity wires because their legs are short. They may also sit on animals that are eating grass. They can make many different sounds, but a common one is a two-note tee-hee call that sounds like the Shikra (Accipiter badius).
Distribution and Habitat
Most of the time, the black drongo bird lives in open country and hunts close to the ground. Most of the time, they hunt insects from the air, but they also eat things they find on the ground or on plants. They visit northeastern Afghanistan and northern Pakistan in the summer, but they live from the Indus Valley to Bangladesh, India, and Sri Lanka.
Some populations move seasonally in ways that are not well understood, while it is known that populations in Korea migrate. The black drongo lives in places like the savanna, fields, and cities. Before the Second World War, black drongos were brought from Taiwan to the island of Rota to help get rid of bugs. People think that in the 1950s, they moved across the sea to the island of Guam.
By 1967, they were the fourth most common bird seen along roads on Guam. Today, they are the most common bird on the island. Some people think that black drongos are a reason why endemic bird species like the Rota bridled white-eye and the Guam flycatcher are becoming less common.
Food and Foraging Behavior
The black drongo bird gets up before dawn and goes to sleep later than most other birds. They mostly eat bugs like grasshoppers, cicadas, termites, wasps, bees, ants, moths, beetles, dragonflies, and ants. They sometimes fly close to tree branches to try to scare away any bugs that might be there. They gather in fields that are being plowed, where they pick up caterpillars and beetle grubs that are exposed.
People have seen as many as 35 birds in these groups. They are also drawn to fires in scrublands and grasslands, which make insects move around. They don’t seem to like flies. They hang out with birds like common mynas, cattle egrets, and others that eat and live in the same places.
Drongos are more successful at finding food when they stick together. Mynas and drongos both eat insects, but they don’t eat the same ones. Sometimes, drongos will steal insects from mynas. People say that they imitate the Shikra’s call to scare away mynas and then steal their food. The fork-tailed drongo does something similar by making false alarm calls.
The black drongo has been known to eat small birds, reptiles, and maybe even bats. Some people think that when they migrate, they might eat more birds. On a stopover island for migrating birds in Korea, one person caught several birds one after the other. They killed the birds by hitting them in the back of the head and neck and then eating only certain parts of them, especially the brain. They have also been seen eating fish from time to time.
They can get water and food from the flowers of trees like Erythrina and Bombax, and they have also been known to eat grains. In contrast, larger arthropods like scorpions and centipedes are rarely seen in their diet. They eat milkweed butterflies, which most other predators try to avoid. They are also known to feed late at night or during the night, often on insects drawn to lights.
Nesting And Breeding
In southern India, most black Drongos have their young in February and March. In other parts of the country, they don’t have their first crop until August. During the breeding season, both men and women sing in the morning. During courtship, they may chase each other in the air and lock their wings and beaks together, which can cause them to fall to the ground. Shows can be set up on the ground.
The bonds between a male and a female last for the whole season. The nest is a cup made of a thin layer of sticks put in the fork of a branch. It takes the males and females a week to build it. Around the first rain in April, the birds lay their eggs. Most of the time, three or sometimes four eggs are laid in a cup-shaped nest in the fork of a tree branch on the outside. Large trees with a lot of leaves, like the jackfruit, are best.
The eggs are 26 mm (1.0 in) long and 19 mm (0.75 in) wide. They rnge in color from pale cream to red and have spots and other marks on them. Both parents take care of the eggs until they hatch after 14 to 15 days. The parents take care of the babies for the first five days. After that, the babies can keep their body temperature pretty steady on their own. If the first one is killed, the bird may lay a second one. Some birds build their nests on telephone poles.
There is a nesting territory that is kept that is 0.003 to 0.012 km2 (0.3 to 1.2 hectares) in size. The helpers, who are offspring from the previous brood, have been seen helping the parents feed their young at the nest. There have been reports of the Asian koel taking care of other birds’ young. On average, only 44% of eggs were fertilized. The main reason young birds died was because they didn’t have enough insects to eat, which depended on the weather.
Mobbing and Proximity Nesting
It is thought that the way they scare away predators from their nests makes it more likely for other birds, like orioles, doves, pigeons, babblers, and especially bulbuls, to nest nearby. In one study, red-vented bulbuls were found nesting near 18 of 40 nests (33 ft). A red-vented bulbul was seen feeding the chicks of a black drongo at their nest, which is a strange thing to see. They are so aggressive that when they are mobbing, they may sometimes land on big birds of prey and peck at them.
Some people think that the Asian drongo-cuckoo (Surniculus lugubris) has changed over time to look like this species. On Java, the intensity of mobbing predators was studied, and it was found that some predators, like the Javan hawk-eagle, were mobbed a lot more during the nesting season. However, the black eagle, which is also a nest predator, was mobbed the same amount in all seasons. It has been said that this might keep people from finding out where nests are during the breeding season.
Increasing in Size and Sophistication
The gape of young birds is yellowish-red. On the fourth day, the feather follicles show up, and after a week, the pin feathers come out. The weight of nestlings stays the same until they are 12 days old. On the eighth day, the eyes open, and the iris is reddish-black and the gape is red. The babies leave the nest between 16 and 20 days after they hatch. Before three weeks, they didn’t have the fork in the tail.
For a month, the parents continue to feed and protect them. Young birds may beg for food for longer, but adults usually don’t pay attention or chase them away. Birds are ready to have babies after about two years. Birds have been seen playing by throwing a leaf into the air and catching it in midair. This may help young birds learn how to do tricks in the air. From June to October, they lose their feathers in southern India.
The wing moult starts with the first primary in July and goes on until the tenth. When the primary leaves reach the third quill in August, the secondaries are changed. The secondary moult doesn’t happen in a straight line; the 8th and 7th are lost before the rest. The tail feathers fall out in a circular motion. Changes in how much melanin is made cause the testicles to change color with the seasons. During the breeding season, the dark pigment is lost.
Relation to Human Culture
In central India, people believe that a cow’s horn will fall off if a young bird lands on it. Some people in Punjab respect it because they think it brought water to Husayn ibn Ali, who is respected by Shi’a Muslims. Beekeepers don’t like them because they eat bees, but farmers bring them to their fields so they can eat pest insects. They do this by putting artificial perches in the fields. Since they are common, they have many local names. The old name for the genus, Buchanga, came from the Hindi word Bhujanga.
Other local names include “srigunting hitam” in Indonesia, Thampal in Pakistan, Gohalo/Kolaho in Baluchistan, Kalkalachi in Sindhi, Kotwal (=policeman) in Hindi; Finga in Bengali; Phenshu in Assamese; Cheiroi in Manipuri; Kosita/ Kalo koshi in Gujarati; Ghosia in Marathi; Kajalapati in Oriya; Kari kuruvi (charcoal bird), Erettai valan (two tail) in Tamil; Passala poli gadu in Telugu; Kaaka tampuratti (queen of crows) in Malayalam; Kari bhujanga in Kannada and Kalu Kawuda in Sinhalese.