With the mango season at its peak, songs of the cuckoo bird are at an all time high filling the air. It is the wooing season for the male cuckoo which lasts from April to September. The male bird sings songs to woo the female bird.
The shy nature of cuckoo bird or koel, as it is commonly called, has kept this bird away from eyes of researchers and often led to the myth that it is the female koel whose songs lure us.
Professor Dinesh Bhatt, a noted bird scientist of Gurukul Kangri Vishwavidyalaya in Haridwar who is Asia representative in bird communication research says, “Koel is very vocal during the breeding season and more often its presence is known by its calls rather than by seeing it. Female koel merely produces shrill kik-kik-kik, a call which is neither melodious nor continuous. It is the male that sings the familiar song kooo-ooo.”
Heading a team of researchers, Bhatt has studied the vocalisation behaviour of Asian koel for the past few years. Speaking to The Pioneer, he said, “People usually think of the koel as a melodious and complex singer, though there are many other avian species such as magpie robin, brahmini myna and pied bush whose voice is much more melodious that koel and produce a large variety of acoustic signals.
This has been revealed by spectrographic analysis in laboratory.” Notably the avian diversity and bioacoustics laboratory developed by Dinesh Bhatt at the university is the one and only laboratory in India that is dedicated to the bird communication research.
After monitoring 126 nests of the house crow, scientists observed that the breeding period of the koel depends on the breeding cycle of its host- the house crow. It has only a single breeding season of about four months from late April to early August.
It forms the pair during third or fourth week of April and pair once formed remains together for the duration of the breeding season. The pair of koel performs secret courtship behaviour mostly inside the dense bushes.
Bhatt who has taken several video shots of these remarkably secret moments, reveals,that the courtship in koel consists of the male chasing the female and the chase often ends up in the female surrendering to him in the branch of a tree. Thereafter she is fed with the fruit by the male before the act of copulation.