NEW DELHI // In 1984, when Sheetal Vyas was a young girl living in Hyderabad, her family built a house that seemed to fill immediately with sparrows. "They'd come in through the ventilation shafts. They'd be sitting around inside the house, or on the window sills," Ms Vyas, an amateur birder, recalled. "I'd be worried that the ceiling fans would hurt them."
Then, gradually, the sparrows started to dwindle. Ms Vyas would see them only when she went to the grocery store, where they fought over the grain that had spilt out of sacks. Last year, on her street, she spotted sparrows once. "They're so rare now that you remember them when you see them, and you get really thrilled," said the freelance journalist.
As India's cities have expanded, getting rid of trees and open space while adding concrete and buildings, their populations of sparrows have plummeted.
The common house sparrow is an indicator species, Atul Sathe from the Bombay Natural History Society (BNHS), said last week.
"If you can find trends in the sparrow population, you can deduce trends about the health of the entire urban ecosystem."
But there exists no reliable count of the sparrows in India's cities, Mr Sathe said. However alarming the drop in the numbers of the bird, all evidence has been anecdotal. "And it's such a small bird and it's found everywhere. So researchers cannot really hope to reach out to every party of India to count it," he said.
Citizen Sparrow, launched on April 1 by the BNHS and several other Indian natural history organisations, and funded by the government's ministry of environment and forests, now hopes to fill in this large data gap.
The project, which runs through the months of April and May, invites people to register sparrow sightings on its website, providing numbers, geographical locations, and details of past sightings. In the first two days, Mr Sathe said, 2,000 people signed up to start posting. That number has now risen to nearly 3,200. "The data we get won't be exact," he said. "But we can get an idea of recent trends and of the present status from various parts of India."
Just as the sparrow itself can be found all over the world, so can evidence of its decline. In the United Kingdom, a campaign run by The Independent newspaper a decade ago was motivated by findings that sparrow numbers had dropped by 90 per cent in 15 years.
In about the same time span, French ornithologists calculated that Paris had lost 200,000 sparrows. A 1999 study showed that Hamburg, Germany had lost 50 per cent of its sparrows in 30 years. In January, researchers in Japan concluded that the sparrow population in the country had fallen by 60 per cent in 21 years.
No reason has been proven to have caused this decline. Denis Summers-Smith, one of the world's leading experts on sparrows, has called it "one of the most remarkable wildlife mysteries of the last 50 years," and a £5,000 (Dh29,209) prize, offered in 2000 by The Independent for scientific proof explaining the sparrow's disappearance, still remains unclaimed.
Aasheesh Pittie, a Hyderabad-based birder and the author of Birds in Books: Three Hundred Years of South Asian Ornithology, has some theories, all of which point to the ways in which the Indian city has evolved. Houses in the city no longer have courtyards or gardens or quiet nesting spaces in which sparrows can come to rest, he said. Instead, cities now have apartment buildings bunched close together, interspersed with stretches of concrete.
Mr Sathe, of the BNHS, believes the radiation from telecommunications towers could be keeping smaller birds away from cities.
Mr Pittie noted also that people hardly stored loose grain in large quantities at home any more. "Now we buy it all at the supermarket."
The rare green spaces within the city are also sprayed with insecticides and herbicides, further depriving sparrows of food.
"A worrying aspect is that young sparrows in nests are surviving less and less," he said. "That is the stage when sparrows hunt for insects to feed their young."
Even now, however, as soon as Mr Pittie gets out of the city on one of his birding trips, he starts to see the sparrow again.
He recently reported to Citizen Sparrow a sighting of 40 to 50 of the birds in a small village just a kilometre from the main highway between Hyderabad and Mumbai.
"In the olden days, they used to send a canary down a coal mine to see if the air was good enough to breathe or not," Mr Pittie said. "Likewise, the health of the sparrow is an indicator of the quality of life that we have given ourselves or the quality of life that we are blindly being led into."