Birders notice decrease in koel population

The Asian koel (called kogile in Kannada) has become hard to spot in the city, says K Sankara Rao, a visiting professor at the Indian Institute of Science (IISc).

A distinguished fellow at the Centre for Ecological Sciences at IISc, Rao is also the author of ‘Trees of Bangalore’ — a book on the city’s rich botanical history. “While Bengaluru doesn’t really have a spring season, many consider the months of March and April as spring, when it is actually early summer. It is around this time that you see colourful blooms across the city, and along with that, you’d also get to hear the sweet sound of the koel singing,” he shares. However, in the past few weeks, he has only heard their melodious call once.

“While along with other bird species, the koel has also been dwindling in numbers, such low visibility is unheard of,” adds Sanjaynagar resident.

Metrolife asked birders how often they had spotted the koel in recent months. While most birders who reside in central Bengaluru said they’d either heard or seen the koel multiple times this year, residents of north and south Bengaluru shared a different experience. Koels tend to inhabit areas where crows abound, shares M B Krishna, a resident of Basavanagudi. He has been birdwatching for over five decades.

“The koel is a deceitful con artist. It is a brood parasite that manipulates other birds to raise its young,” he shares. It lays its eggs in the nests of other bird species, such as crows. The unsuspecting host birds incubate the eggs and raise the koel chicks as their own. This helps the koel avoid the energy costs of parenting and increases survival chances. He believes the drop in the population of crows is impacting the koels.

“Loss of nesting sites is one of the main causes for the declining number of crows. Crows need dense patches of trees to build their nests. A lone tree in an apartment complex won’t do. Adding to this is the pollution and reduced availability of food, such as dead rats,” adds Rao.

Currently, Prasad J N, a birdwatcher based in J P Nagar, has a pair of koels visiting him every morning. “But, in previous years, by the time April rolls around, I’d get to hear at least five pairs of koels singing every morning. But that’s not surprising because the number of house crows in my area has dramatically decreased,” he says. Sabiha M, a birdwatcher from R T Nagar, has also noticed similar patterns.