Asian koel birds (Eudynamys scolopaceus) are medium-sized, olive-green colored birds with black bills and white bars on their wings. A defining characteristic of this bird, which is in the same family as cuckoos, is the fact that it does not build its own nest and instead lays its eggs in the nests of other birds.
Asian koel birds are native to India, Sri Lanka, Malaysia, Indonesia, Thailand, and Australia. They can be found as far north as Japan and Russia and as far south as New Zealand and New Caledonia.
Eudynamys scolopaceus is a small passerine bird and one of the many species of birds that have distinctive calls that have been used in the development of the musical instrument known as the didgeridoo. Their plumage ranges from shiny green in males to duller olive green in females and non-breeding males.
Asian koel birds are non-migratory birds that belong to the cuckoo family, Cuculidae. The various subspecies are distinguished by their respective colors and body sizes, with females generally larger than males.
While their appearance may be somewhat similar to other cuckoos (especially in the area around the eyes), there are several physical characteristics that set Asian koels apart from other species in their genus.
Asian koel description
The Asian koel bird is a member of the cuckoo family and is found in wooded areas throughout South Asia. The bird is easily identified by its black plumage with white wing markings.
The male also has a distinctive call that is often heard early in the morning. Asian koel birds are not shy and will often stay very close to human habitation humans. The bird’s diet consists mostly of fruits, but they will also eat insects and small reptiles.
They build their nests on the ground or on tree branches and lay between four to six eggs each breeding season. They are monogamous which means they only have one mate at a time.
The scientific name of the Asian koel bird is Eudynamys scolopaceus
Habitat & distribution
The Asian koel is a tropical bird found in parts of South and Southeast Asia. In the wild, they typically inhabit forests and woodlands, but can also be found in urban areas. They are also sometimes kept as pets. Male birds sing beautiful songs to attract females during mating season, which peaks in December.
Towards the end of summer or early fall, they migrate southwards. Males typically have a song that signals their intention to mate; one variant is an imitation of a saw being sharpened on an oilstone, given repeatedly with increasing intensity as the male flies overhead for up to 20 minutes at dusk or night time looking for females.
Size and weight
The Asian Koel is a member of the cuckoo family. It is a large bird, measuring about 15 – 18 inches in length and weighing up to 190 – 327 g. The male bird is larger than the female, and both sexes have dark plumage with some lighter markings.
Feather and plumage
The Asian Koel is a strikingly plumaged bird. The adult male has a glossy black head, neck, and breast, with a white band around the lower breast. The back and wings are dark brown, and the tail is black with three white bars.
The female is similar in plumage, but with a brown head and neck, and lacks the white band around the lower breast. Both sexes have red eyes and long, curved bills. Juveniles are similar to adults, but with browner plumages.
One of the most interesting things about the Asian Koel bird is that it molts. This process can take up to six weeks, during which time the bird will lose all its feathers and grow new ones.
The molting process is believed to help the bird stay cool in hot weather and also protect it from predators. Birds have many enemies; some like hawks prey on them while others, such as rats, eat their eggs. In this way, molting helps birds to be less vulnerable when they are not fully protected by their feathers.
These days scientists think that koels may use molt cycles to prepare for migration. Some evidence suggests that they go through a molt before they head south, in order to better adapt themselves to climate change or because the food supply has dwindled.
As is true of many of its related cuckoo relatives, the Asian koel is a brood parasite that lays its eggs in crows’ nests and other hosts that raise its young. Unlike many of their cuckoo kin, they are mainly frugivorous as adults.
They typically nest in trees, often close to human habitation. The nest is a large platform of twigs, leaves, and grass, lined with soft materials such as feathers. Eggs are incubated for 18 days by both parents.
They will generally lay two eggs at a time, but if the first egg hatches before the second one has finished incubating, they will abandon the remaining egg. If food is plentiful then both eggs are likely to hatch successfully, but if food becomes scarce then only one chick will survive after hatching.
Asian koel food and foraging
The diet of the Asian Koel bird consists mainly of fruits, but they will also eat insects, frogs, lizards, and small snakes. They forage at ground level, in bushes and trees, looking for food on the ground or in low-lying vegetation. They are attracted to areas where there is water nearby and are often found foraging near streams or ponds.
Sounds and vocal behavior
The Asian Koel is a vocal bird, known for its loud and sometimes ear-piercing calls. The male has a distinctive two-note call, often heard early in the morning or late at night. The female has a higher-pitched call that sounds more like kee-yah. Both sexes also make other sounds, including grunts, chuckles, and hisses.
The Asian koel is a nest parasite, meaning that it deposits its eggs in the nests of other birds. Sometimes the male will distract the hosts to give the female a chance to lay an egg in the nest.
Instead, more often the female visits the nest of the host by herself.
The koel does not lay eggs in an empty host nest, and a study in Pakistan found that the first koel eggs were laid, on average, one and a half days after the host’s first egg. The koel chicks hatched 3 days ahead of the host chicks.
Typically, a koel lays only one or two eggs in one nest, but it has been reported that some hosts’ nests have up to seven or eleven. Before laying, a female koel will sometimes remove a host egg. Twelve to fourteen days is how long it takes for an egg to hatch.
The young koel does not always push out eggs or evict host chicks, and initially calls like a crow. Fledge occurs in 20 to 28 days. The young cuckoos do not kill the host chicks, as they do with other cuckoo species, but they are more frugivorous as adults, which is shared with the channel-billed cuckoo.
Koels tend not to evict chicks from their nests, like some other brood parasites, presumably due to the high cost of evicting rival nestmates. Large parasites cannot easily evict large host eggs or chicks from deep Corvid nests without risking starvation or accidental self-eviction.
Koel female parents have been known to feed young koels in the nests of their hosts, which is similar to the behavior seen in other brood parasitic species. However, it did not gain much support. Males have not been observed to feed fledglings.
The Asian Koel bird has a lifespan of about 10-15 years. In the wild, they typically live around 12 years, but in captivity, they can live up to 15 years. The oldest recorded Asian Koel was 19 years old.
Movements and migration
These birds are usually found in forests and woodlands, but can also be seen in urban areas. They are known for their loud call, which is often heard early in the morning. Asian Koel birds are not migratory, but they may make local movements in search of food or suitable nesting sites.
In China, the species has around 10,000-100,000 breeding pairs and approximately 1,000-10,000 individuals on migration, while Taiwan has less than 50 individuals on migration and around 100-10,000 breeding pairs.
Conservation and management
The Asian Koel is a large bird found in the tropical forests of South and Southeast Asia. The species is listed as the least concern by the IUCN due to its large range and population. However, the bird is considered a pest in many areas due to its loud call and crop-damaging habits.
In some places, such as Singapore, hunting of the Asian Koel is regulated in order to control numbers. Otherwise, there are no major conservation measures in place for this species.