The Asian Koel is one of our most familiar birds because of its loud rising and seemingly manic “ko-el ko-el” call (which is, rather annoyingly, sometimes uttered in the middle of the night). In addition, it parasitises House Crows so it is often seen around human habitation and in urban areas. It is mostly a summer visitor to our area although a few may over-winter, subsisting on berries. Most birds arrive in March and have gone by November. It is assumed that they move into warmer climes further south in India where they also occur as residents.

Since their hosts are House Crows, they tend to occur wherever this species is found. They are wide-spread and gaps in the maps almost certainly reflect observer coverage. They feed on berries, particularly of the various fig (Ficus) trees and also rob small birds’ nests.

Koels are a similar size to their hosts and the males are black, suggesting that they mimic crows  for some reason. Of course it is the brown and white females that deposit the eggs so the males’ mimicry (if that is what it is) cannot be for disguise. In addition male Koels make no effort to avoid their hosts and often seem to be actively consorting with them. Is it possible they do this to distract the crows and thus enable the female to approach the crow’s nest?

Although the newly hatched Koel does not eject the eggs and/or young of its host, the egg has a shorter incubation period and the young Koel can therefore monopolise the food and in the process starve its nest mates. The juveniles actually caw like crows and spend an extended period following their foster parents around and noisily begging for food.