The little bird that used to be a common sight till a few years ago is dwindling in numbers. It is a welcome surprise to see it flitting about, chirping merrily away: that is no longer a commonplace occurrence now.
Believed to be one of the oldest companions of human beings, the sparrow (Passer domesticus) is disappearing from much of its natural range, both in the urban and rural habitats both as a result of and leading to degradation of the environment. Due to a decrease in numbers, a bird as common as the sparrow was included by the IUCN in its Red List of threatened species in 2002 alongside the glamorous snow leopard, tiger, and red panda.
This day, March 20, is observed as the World Sparrow Day, to draw attention to the need to remove threats to the bird and its habitat and conserve urban biodiversity. World Sparrow Day was first celebrated in 2010 when members of the Nature Forever Society started communicating the need to save these birds with the help of national and international organisations.
In Delhi, the sparrow was adopted as the State bird in 2012.
We need to know the detrimental effects of pollution which have caused the slow death of this avian that once co-existed with us. A media report said the population of house sparrows has seen a slight increase in the slums of Delhi, according to a survey by ecologists who also found that the birds’ numbers have increased in some pockets of slums of the city as against the planned areas.
The study said sparrows were rarely sighted in the planned areas because they have lost their natural habitat for nesting. Other factors behind the decline in their numbers include non-availability of food, use of pesticides in farmlands, electro-magnetic radiation from mobile towers, noise and air pollution.
Big birds like pigeons that multiply fast and occupy the small number of places and holes for building nests also edge out the much smaller sparrows. The blue rock pigeon is the main culprit in taking over the sparrows’ nesting areas.
A report in The Hindu, quoting ecologist and ornithologist MB Krishna, said urbanisation and loss of agricultural fields was an important factor. He said the chicks of sparrows are very tiny and feed on insects. But, the insect populations itself is going down either because there are fewer plants which attract insects or the over use of pesticides, which kills them.
“Another problem is the lack of nesting and roosting sites. What we need is incorporating greenery in modern planning,” he said.
The sparrows have adopted new sites for nesting in Delhi, according to ecologist TK Roy, as quoted by The Asian Age. “As per the study, house sparrow population has partially increased in some pockets of slum areas of the capital because of adoption of alternative nesting sites — shop shutter tops, inverted lamp sheds, ventilators, modern flyover wall holes and used hard paper board open boxes on the roof rooftops,” he said.
Most sparrows have shifted to the outskirts of Delhi, said a report in TOI, quoting birder Nikhil Devasar. “The sparrow concentration has shifted to forests and urban villages outside Delhi. The fact is urban areas now have fewer trees and greenery where the sparrows can nest. Of course, the blue rock pigeons have also colonised places where sparrows can make nests.”
Faiyaz Khudsar, scientist in charge at the Yamuna Biodiversity Park, said that non-availability of nesting space was one of the biggest reasons for the flight to the outskirts. “Today’s urban constructions are not sparrow-friendly — the bird cannot find resting space and finding food is also difficult because availability of insects and worms has reduced due to the use of insecticides and pesticides,” said Khudsar.
Experts agree that the birds could be brought back to the city if feeders and nest-boxes were provided in large numbers.