The Asian Koel is a member of the cuckoo order of birds, the Cuculiformes.It is found in South Asia, China and Southeast Asia. It forms a super species with the closely related Black billed and Pacific Koels which are sometimes treated as subspecies. The Asian Koel is a brood parasite that lays its eggs in the nests of crows and other hosts, who raise its young. They are unusual among the cuckoos in being largely frugivorous as adults. The name Koel is echoic in origin with several language variants. The bird is a widely used symbol in Indian poetry.
The Asian koel is a large, long-tailed, cuckoo measuring 39-46 cm(15-18 in) and weighing 190-327 g(6.7-11.05 oz). The male of the nominate race is glossy bluish-black, with a pale greenish grey bill, the iris is crimson, and it has grey legs and feet. The female of the nominate race is brownish on the crown and has rufous streaks on the head. The back, rump and wing coverts are dark brown with white and buff spots. The underparts are whitish, but is heavily striped. The other subspecies differ in colouration and size. The upper plumage of young birds is more like that of the male and they have a black beak. They are very vocal during the breeding season(March to August in South Asia), with a range of different calls. The familiar song of the male is a repeated Koo-Ooo. The Female makes a shrill kik-kik-kik... call. Calls vary across populations. The Asian Koel is a brood parasite, and lays its single egg in the nests of a variety of birds, including the Jungle Crow and House Crow. Host nests at low heights and nearer to fruit trees tended to preferred by koles.
Males may distract the hosts so that the female gets a chance to lay an egg in the nest. More often however, the female visits the nest of the host alone. The Koel is not known to lay eggs in an empty host nest and a study in Pakistan found that the first Koel eggs were laid, on average, within one and half days of the laying of the host's first egg. The chicks of the koel hatched about 3 days ahead of the host chicks. Koels usually lay only an egg or two in a single nest but as many as seven to eleven eggs have been reported from some host nests. A female may remove a host egg before laying .Eggs hatch in 12 to 14 days. The young Koel does not always push out eggs or evict the host chicks and intially calls like a crow. The young fledge in 20 to 28 days. Unlike as in some other cuckoos, the young do not attempt to kill the host chinks,a trait that is shared with the Channel-billed Cuckoos which are also largely chicks due presumably due to the higher cost of evicting nestmates. A small parasites may not be able to evict large hosts eggs or chicks from a deep Corvid nest without risking starvation and possibly accidental self-eviction.An alternate hypothesis that retaining host chicks might benefit the Koel chinks did not gain much support. Adult female parents have been known to feed young koels in the nests of the hosts, a behaviour seen in some other brrod parasitic species as well. Adult males have however not been noted to feed fledgings. The Aisan Koel is omnivorous, consuming a variety of insects, caterpillars, eggs and small vertebrates. Adults feed mainly on fruit. They will sometimes defend fruiting trees that the forage in and chase away other frugivores. They have been noted to be especially important in the dispersal of the sandalwood tree(Santalum Album) in India. Large seeded fruits are sometimes regurgitated near the parent tree while small seeded fruits are ingested and are likely to be deposited at greater distances from the parent tree. They have a large gape and are capable of swallowing large fruits including the hard fruit of palms such as Arenga and Livistona. They have been known to occasionally take eggs of small birds. They feed on the fruits of Thevetia peruviana which are known to be toxic to mammals.
The word "Koel" is onomatopoeic in origin. The Sanskrit root is " Kokila" and words in various Indian languages are similar. It is traditionally held in high regard for its song and held in reverence with the Manusmriti, an ancient decree protecting them form harm. The vedas, Sanskrit literature dated to about 2000 BC referred to it as Anya-Vapa which meant " that was raised by others"(or"sown for others to reap"). This has been interpreted as the earliest knowledge of brood parasitism. Being familiar birds with loud calls, references to them are common in folklore, myth and poetry. It has been chosen as the state bird by the southern Indian State of Puducherry.
These birds were once very popular in India as cagebirds. Feeding even on boiled rice, these hardy birds lived in captivity for as long as 14 years.
This bird has a strong association with the Traditional New year celebrations of Sri Lanka. In the literature around the festival , the song of the bird is regarded as heralding the traditional new year. This bird is known as the koha in Sri Lanka by the Sinhala speaking community.
The Asian koel is a large, long-tailed, cuckoo measuring 39-46 cm(15-18 in) and weighing 190-327 g(6.7-11.05 oz). The male of the nominate race is glossy bluish-black, with a pale greenish grey bill, the iris is crimson, and it has grey legs and feet. The female of the nominate race is brownish on the crown and has rufous streaks on the head. The back, rump and wing coverts are dark brown with white and buff spots. The underparts are whitish, but is heavily striped. The other subspecies differ in colouration and size. The upper plumage of young birds is more like that of the male and they have a black beak. They are very vocal during the breeding season(March to August in South Asia), with a range of different calls. The familiar song of the male is a repeated Koo-Ooo. The Female makes a shrill kik-kik-kik... call. Calls vary across populations. The Asian Koel is a brood parasite, and lays its single egg in the nests of a variety of birds, including the Jungle Crow and House Crow. Host nests at low heights and nearer to fruit trees tended to preferred by koles.
Males may distract the hosts so that the female gets a chance to lay an egg in the nest. More often however, the female visits the nest of the host alone. The Koel is not known to lay eggs in an empty host nest and a study in Pakistan found that the first Koel eggs were laid, on average, within one and half days of the laying of the host's first egg. The chicks of the koel hatched about 3 days ahead of the host chicks. Koels usually lay only an egg or two in a single nest but as many as seven to eleven eggs have been reported from some host nests. A female may remove a host egg before laying .Eggs hatch in 12 to 14 days. The young Koel does not always push out eggs or evict the host chicks and intially calls like a crow. The young fledge in 20 to 28 days. Unlike as in some other cuckoos, the young do not attempt to kill the host chinks,a trait that is shared with the Channel-billed Cuckoos which are also largely chicks due presumably due to the higher cost of evicting nestmates. A small parasites may not be able to evict large hosts eggs or chicks from a deep Corvid nest without risking starvation and possibly accidental self-eviction.An alternate hypothesis that retaining host chicks might benefit the Koel chinks did not gain much support. Adult female parents have been known to feed young koels in the nests of the hosts, a behaviour seen in some other brrod parasitic species as well. Adult males have however not been noted to feed fledgings. The Aisan Koel is omnivorous, consuming a variety of insects, caterpillars, eggs and small vertebrates. Adults feed mainly on fruit. They will sometimes defend fruiting trees that the forage in and chase away other frugivores. They have been noted to be especially important in the dispersal of the sandalwood tree(Santalum Album) in India. Large seeded fruits are sometimes regurgitated near the parent tree while small seeded fruits are ingested and are likely to be deposited at greater distances from the parent tree. They have a large gape and are capable of swallowing large fruits including the hard fruit of palms such as Arenga and Livistona. They have been known to occasionally take eggs of small birds. They feed on the fruits of Thevetia peruviana which are known to be toxic to mammals.The word "Koel" is onomatopoeic in origin. The Sanskrit root is " Kokila" and words in various Indian languages are similar. It is traditionally held in high regard for its song and held in reverence with the Manusmriti, an ancient decree protecting them form harm. The vedas, Sanskrit literature dated to about 2000 BC referred to it as Anya-Vapa which meant " that was raised by others"(or"sown for others to reap"). This has been interpreted as the earliest knowledge of brood parasitism. Being familiar birds with loud calls, references to them are common in folklore, myth and poetry. It has been chosen as the state bird by the southern Indian State of Puducherry.
These birds were once very popular in India as cagebirds. Feeding even on boiled rice, these hardy birds lived in captivity for as long as 14 years.
This bird has a strong association with the Traditional New year celebrations of Sri Lanka. In the literature around the festival , the song of the bird is regarded as heralding the traditional new year. This bird is known as the koha in Sri Lanka by the Sinhala speaking community.
No comments:
Post a Comment