Common Myna, an all-season bird with an aggressive streak


The Common Myna (Acridotheres tristis) is an all-season and common resident bird in the Tricity — Chandigarh, Mohali and Panchkula – area.

The Common Myna is identified by its black head and breast, which merges into an overall brownish plumage, and a prominent yellow orbital skin patch and bill. Easily found in bursting-to-the-seams urban areas and faraway rural areas, its overall length is 25 cm. The male and female are alike.

The Common Myna is believed to pair for life. It breeds through much of the year, depending on the location, building its nest in a hole in a tree or wall. The normal clutch size is 4-6 eggs. The incubation period is 17 to 18 days and fledging period is 22 to 24 days. While common mynas normally use twigs, roots, tow and rubbish as nesting material, they have also been known to use tissue paper, tin foil and sloughed-off snake skin.

The Common Myna uses the nests of woodpeckers, parakeets etc. and easily takes to nest boxes. It has been recorded evicting chicks by holding them in its beak, and sometimes, does not even use the emptied nest box later. This aggressive behaviour contributes to its success as an invasive species.

These days, in a worrying trend, several instances of deformities have been reported in the Common Myna in Chandigarh. Observers, including birders and ornithologists, say deformities among bird species are common but more such cases have been found in Common Myna. The most common deformity is a bald head and neck, with the fur and feathers on its head disappearing. Experts believe that genetics and hormonal imbalance are the reasons causing this baldness.

Like most starlings, the Common Myna is omnivorous. It feeds on insects, arachnids, crustaceans, reptiles, seeds, grains and discarded waste from human habitation.

I got a chance to observe a pair of Common Myna, including one with a completely bald head and neck, at Panjab University (PU) recently. The pair were picking and feeding on insects in a small flower bed freshly filled with cow/buffalo dung compost. The pair were working in tandem and no awkward behaviour was seen on the part of the healthy bird towards the myna with deformities.

In an online interview with The Indian Express in September 2019, Dr Vibhu Prakash Mathur, a principal scientist with Bombay Natural History Society (BNHS), had said that there were many reasons for deformities among birds like mal-positioning of embryo in the egg during incubation, or injury on the skull or due to poor nutrition in food.

“It could also be due to bacterial, viral or parasitic infections. The studies done in the US have, however, indicated that wherever a large number of birds in an area were found with deformity, it was due to a novel virus They used the latest techniques in molecular biology called deep sequencing and isolated a novel virus related to a group of virus called avian picornaviruses. They, however, ruled out other viral, bacterial or parasitic infections or malnutrition as causes of deformity,” he had said.


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