The sparrows at Bengaluru’s international airport almost made Mohammed Dilawar miss his flight. Early one morning, he was waiting to board a connecting flight to Mengaluru, but as he watched the birds flitting in and out of shops and feeding on crumbs left on the grey tiled floor, he nearly forgot there was a plane to catch.

Dilawar, who is the president of the Nature Forever Society, a nonprofit dedicated to the conservation of house sparrows, tries to get to the airport at least two hours before his flight to watch house sparrows living in their glass-and-steel habitat. A pair of binoculars and a pen in hand, he has even had to ask airport security for permission to watch the birds, lest he seem suspicious.

To Dilawar, and others like him, the seemingly large population of the house sparrow or Passer domesticus at the Kempegowda International Airport is beguiling, not least because of reports that the bird’s population has dwindled in the city centre over the past several years.

“All their ecological needs are met at Bangalore airport,” he said.

The Sparrow Airport

Driving up to Bengaluru’s international airport, you’ll first notice its curved glass façade, interrupted by angled pillars that keep the structure grounded. Inside the airport, small crevices are formed on top of beams, around pillars and between slats of skylights that bring natural light into the cavernous space. These nooks, experts say, are ideal for birds like house sparrows, or even crows, to build nests. And although the sparrow population may not be immediately apparent when you walk into the airport, take a moment to listen carefully. Over the low thrum of passengers talking and luggage wheels scraping against the floor, the sound of birds chirping has become an unmistakeable part of the airport’s ambient soundtrack.

Kempegowda International Airport. Credit: Pixabay/Wikimedia Commons [Licensed under Creative Commons Zero]

In 2013, Harish Bhat, a research scientist at the Indian Institute of Science’s Centre for Ecological Sciences, estimated there were roughly 400 sparrows at what he called the “Sparrow Airport”. In an article in The Hindu, he said that this stable population was unlike any other he had encountered. For one, the house sparrows are bolder and often feed on food scraps left on tables in restaurants and lounges before they can be cleared away. “They get five-star food,” Dilawar said.

Crumbs however aren’t enough for these birds to survive. Large tracts of natural grasslands outside the airport offer both vegetation and insects for the birds to forage on. Nestlings require a steady diet of insects during the first few days of their life in order to grow and thrive. This access to food works out for the house sparrow, a parochial bird that tends to stay in the area where it was born in. It also benefits from the lack of competition for resources from larger birds, like mynas, or danger from predatory animals.

It is another story forty kilometres away, in Bengaluru city.

Flying the coop

House sparrows were once ubiquitous in Bengaluru. They could be found nesting in thatched roofs, behind geysers, between roof tiles, or feeding on fallen grain and seeds on street corners. In keeping with the name, the little bird tended to stick around human settlements, turning nooks and crevices into its comfortable home. This ability to cohabitate with humans is why ornithologist MB Krishna described the bird as “commensal”.

Over the past many years, though, several experts and local birdwatchers have noticed their retreat further and further away from the city into specific, often rural, pockets. News headlines lament this loss to the city – “Where have the sparrows gone?” one article in The Hindu asked in 2014.

Credit: Mike Pennington [Licensed under CC BY-SA 2.0]

The absence of agriculture space in Bengaluru’s city centre could be one reason that house sparrows appear to have mostly disappeared. Roads, flyovers, malls, apartment and office buildings have effectively wiped out the natural vegetation that these high-energy birds need for their survival.

In their working paper, Of Sparrows and Human Settlements, Gubbi Labs, a private research collective, speculates that the decline of the rural house sparrow is “thought to be linked to changes in agricultural practices, particularly the loss of winter stubbles and improved hygiene measures around grain stores”.

Another possible reason is the rise in automobile traffic. “Changes in urban transport have been phenomenal in Bangalore, posing significant challenges for the environment and general well-being [of house sparrows],” according to the paper published in 2013.

“The decline of sparrows in Bangalore is a manmade problem,” said noted ornithologist S Subramanya. Back in the 1980s, he recalled a time when sparrows would feed on broken rice left outside homes or green caterpillars plucked from vegetables. “All those old practices are gone.”

An aerial view of Bengaluru. Image credit: Amol Gaitonde/Wikimedia Commons [Licensed under CC Attribution-Share Alike 3.0]

Too small to care

Despite widespread reports that these birds are fleeing Bengaluru city, little has been done to collect data recording their numbers in recent years, several experts noted. So far, the apparent dwindling population has been primarily supported by anecdotal evidence – people who have grown up in the city just aren’t seeing the little birds in the same way they used to.

Sudhira HS, a researcher at Gubbi Labs and an author of the paper, said that house sparrows could still be found in less developed parts of the city, including KR Market and the railway station at Yeshwanthpur. But without long-term studies into the bird’s distribution or numbers, it is difficult to pinpoint the reason people are seeing these changes. The question remains: is the population declining or are the birds simply leaving their former city habitat?

When Nature Forever Society started its work more than 15 years ago, the house sparrow wasn’t even considered “conservation material”.

“It was all about tigers, it was all about elephants,” Dilawar said.

In March, the society organised a sparrow count to record its distribution around the world, but the number of participants was too small to come up with any solid data. A similar count will be organised during World Sparrow Day on March 20 next year and Dilawar is hopeful that they will have more success in 2018.

Though some national institutions, such as the Indian Institute of Science and the Wildlife Institute of India, are working on long-term monitoring efforts, these projects rarely engage local citizens, Sudhira said. For a real shot at keeping sparrows part of our urban landscape, the public needs to be involved in their conservation.

“We never realise that we’ll be coming to the situation we are in today 40 years back,” Subramanya said. The ornithologist recalled a similar situation involving vultures in Ramanagara, a town about 50 kilometres southwest of Bengaluru which has seen its population decline by 90% in the last two decades.

“We took for granted that these birds are going to be there forever,” he said.