Feral Cities (8 page)

The sparrows stumbled briefly at the one hundredth meridian, the line that divides the moist East of the United States from the arid West and runs along the western border of Oklahoma (excluding the panhandle). But as with the starlings facing the Great Plains, the plucky birds soon overcame that natural obstacle. By 1910 house sparrows had colonized North America. They could be found in northern Mexico, in the cities along the Pacific coast, and in much of southern Canada, where they survived harsh winters by nesting in railroad houses and grain elevators. Come 1917 they had even turned up on the ranches of Death Valley.

The same was happening in South America. Following introductions in Buenos Aires, Rio de Janeiro and Santiago, the sparrow conquered Argentina, Brazil, Chile, Peru and Uruguay. The birds even reached Ushuaia, the world's southernmost city on the Argentine portion of the Tierra del Fuego archipelago. The Amazon rainforest blocked the sparrow's northward advance, but when Brazil began building the Trans-Amazonian Highway in the 1970s, the birds followed the construction workers, making nests in the new buildings and trees lining the 2,485-mile road.

These introductions have made the house sparrow one of the world's most widespread birds, yet wherever it is found it congregates in cities and towns. Half of the UK's sparrows live in urban areas, even though these account for less than one-seventh of the land in Britain. And although they may struggle in the innermost core of cities, sparrow numbers tend to rise rather than fall with urbanization.

One reason for the house sparrow's urban success is its lack of fear. Sparrows may be small but they are brave. While many animals shy away from the unusual, sparrows investigate. This lack of fear makes them well adapted to city life. They are more willing to try unfamiliar food and are less frightened by changes to their environment. It's a characteristic that has seen house sparrows adapt to modern life in surprising ways.

Take the story of Nigel. Nigel was a New Zealand house sparrow and the most frequent visitor to the Dowse Art Museum in the late 1990s. Several times a day, Nigel—as the employees named him—would fly over the streets of Lower Hutt, a suburb of the capital city Wellington, to reach the museum's flat-roofed and white-tiled building.

The automated doors that guarded the entrance would have proved an insurmountable barrier for most birds, but not for Nigel. On reaching the entrance, Nigel would flutter in front of the electronic sensor to trigger the opening of the glass doors. Having fooled the outer doors, he would nip through the entrance
and perform the same trick again to cause the second set of doors to part.

After entering the foyer, Nigel would veer right, past the ticket kiosk and artwork, to reach the indoor cafeteria, where he would hop under chairs and pogo along the tabletops eating scraps left behind by clumsy customers. After filling up on breadcrumbs, potato chips, and other morsels, Nigel would exit the cafeteria, going back past the foyer and the sliding doors to reach the outside world, only to return for another raid shortly after.

Nigel was no one-off. Six hundred miles north of Wellington in Auckland, sparrows had cracked the automated door conundrum in a different way. Instead of hovering in front of the doors, they would land on the rectangular sensor and duck their heads to cause the doorway to open so they could reach the Hamilton InterCity bus station eatery.

More than four thousands miles northeast of Auckland, on the Hawaiian island of Maui, the local house sparrows figured out another way to fill their beaks with people's leftovers. Each morning the birds would hang precariously from the rooftops of the largest beachfront hotels so they could spy on the tourists eating breakfast on the balconies below and swoop down to grab the remains as soon as the vacationers retreated to their rooms.

After breakfast the sparrows would go and feed elsewhere, but come midday they were back in position for the lunchtime service. Maui's other birds would only cotton onto these balcony buffets when they spotted the sparrows flittering to and fro from the hotel facade.

Some urban sparrows have even become night owls. In Bangkok sparrows have been seen late at night, eating moths drawn to the bright lights of the city airport. Likewise in Manhattan, sparrows have been spotted close to midnight feeding on insects near the lights of the Empire State Building's observation deck.

But the house sparrow's presence in cities is now under threat. Across the world urban sparrow numbers are dropping fast. In
UK cities their numbers have fallen 60 percent in the past three decades. It's a similar story in Amsterdam, Brussels, Delhi, Hamburg and many eastern US cities. Today the oldest bird on the city block is fading so fast it is now on Britain's Red List of endangered species, a situation unthinkable just a couple of decades ago. The pattern isn't universal—numbers are stable in the English city of Manchester, for example—but the declines are alarming and the cause unknown.

Will Peach of the Britain's Royal Society for the Protection of Birds is one of the people trying to solve the Great Sparrow Mystery. “Quite often if a familiar bird declines, there's a glut of research projects and you will come up with a plausible explanation fairly quickly,” he tells me from the organization's headquarters, a lodge house nestled within a nature reserve deep in the Bedfordshire countryside. “It's fair to say that with urban sparrows we've had that initial buzz of activity and, so far, it's still a bit of a mystery.”

There is no shortage of theories. Although they eat bread, dog food, and other scraps, sparrows are seed eaters at heart, so some suggested a lack of seed was the problem. But when the theory was tested by supplying seed to the birds year-round, it made no difference.

A lack of the invertebrates that young sparrows are reared on was another explanation. “Where sparrows don't have enough insects they tend to feed their young with bread and peanuts and rubbish like that, and usually you'll see high rates of chick mortality in situations like that,” says Will. But when Will and his team tried dishing out juicy mealworms to London's sparrows, it only helped the smaller colonies and did little to aid larger gatherings of the birds.

Others pointed the finger at pet cats and sparrowhawks. Yet cat ownership in London has changed little in the past twenty years, and studies suggest that cats kill more blackbirds than sparrows anyhow.

The case against sparrowhawks seems more convincing. These small birds of prey, which feed on a variety of birds (not just
sparrows), are making a comeback in British cities after being almost wiped out by the notorious pesticide DDT. But although sparrow numbers are lower in urban gardens where sparrowhawks are active, that could simply be because sparrows avoid the area or evade capture by hiding in dense vegetation. Equally, there are plenty of places where sparrows and sparrowhawks live side by side, suggesting that sparrowhawks simply don't eat enough sparrows to be the sole cause of the decline.

Wilder theories have also been floated. Some suggested that electromagnetic radiation from cell phone masts could be affecting the birds since there are fewer sparrows in places where there are more masts. But, says Will, these are “also the highly urbanized places where you might expect to see fewer sparrows anyway.”

Maybe it's genetic, others suggested. Since sparrows don't travel far, there's little mixing of urban and rural populations of the birds, and city sparrows do have slightly less genetic variation than their country cousins. Trouble is no one knows what, if any, difference that makes.

Architectural changes are a better culprit. Buildings define the urban landscape and have a major bearing on what can and cannot thrive within cities. This theory is supported by a study that looked at how sparrows fare in different areas within English cities. It found that poorer neighborhoods offered more suitable habitat for the birds than the better-off areas. So in Golborne, one of the most deprived wards in London, where the brutalist concrete of Trellick Tower looms over high-crime streets, sparrows should do well. Yet three miles south in Queen's Gate, home to Harrods and the city's super-rich, the sparrow should be a rarer sight.

Like starlings, sparrows have their own architectural preferences. They like houses built before 1945 best—and the more run-down they are the better, because that means there are more holes to nest in. Newer buildings are less welcoming, offering fewer nooks and crannies for nesting. Richer areas also have housing in a better state of repair, and house sparrows are less common
in areas where houses have been renovated in the past decade. “If you replace your rotting, wooden soffit boards with PVC, which a lot of people do, the sparrows are excluded,” says Will, adding that as property prices have risen, more and more Londoners are paving over their front gardens to turn them into parking spaces, which means there are also fewer sources for the seed and insects sparrows eat.

In short, as our cities improve, the house sparrow loses out.

Few places are undergoing as much development as Nashik in Maharashtra, India. This metropolis of one and a half million people is the sixteenth fastest-growing city in the world. Space is tight and the noise of construction is never far away. New high rises are springing up, and so many people are moving in from the countryside that the city is struggling to build the infrastructure needed to cope with them fast enough.

It's a pattern being replicated across India. The country is urbanizing at breakneck speed, and as ramshackle streets with ramshackle houses give way to office blocks and shopping malls, the sparrow is in retreat.

“In my childhood the sparrows were so numerous,” recalls Mohammed Dilawar, who grew up in Nashik in the 1980s. Back then less than half a million people lived there. “At that time in Indian homes you could have sparrows making nests behind the window panes, on top of the cupboards, between suitcases. Even in the homes there were sparrow nests.” Mohammed's own family home had sparrows nesting in the canopy of their ceiling fan. “If it was summer and the sparrow nest was there, you would stop using the fan,” he tells me.

Did people not object to birds living in their homes? I ask. “We were brought up not to disturb the sparrow nest. In those times hygiene and these issues were not so much of a care. That was the kind of culture of we had in India, a very open culture. A culture
where your neighbor could regularly just walk into your home unannounced.”

Sparrows were not the only bird that imprinted itself on Mohammed's childhood. “I used to see hundreds of vultures foraging every day and that used to fascinate me—to see these vultures sitting there. Since we did not have access to a lot of other things, my entire childhood was spent seeing sparrows, birds, and vultures.”

Today, he rarely sees vultures. The few that are left live on the outskirts of Nashik in tiny groups. The fate of the vultures haunts Mohammed: “The Indian species of vulture went from being the most common raptor in the world to being the most critically endangered bird. It only took ten years, which is faster than the extinction of the dodos.”

What he finds saddest is that no one even noticed. “Because of a society that was deprived, we didn't have access to things like television or the mobiles, so when these things came in people got so engrossed in the television and their mobiles they didn't even realize what they were losing around them.”

Mohammed figured that if the vulture could go from abundance to near extinction in a few years then so too could his beloved sparrows. So he decided to act. He founded the conservation group Nature Forever Society and launched World Sparrow Day, an international event designed to raise awareness of the sparrow's plight. He persuaded the government of Delhi to make the sparrow the official bird of the Indian capital and started selling tens of thousands of cheap bird feeders and nest boxes to Indian city dwellers who wanted to give the sparrow a helping hand.

Mohammed says the sparrow is like the tiger—a gauge of ecological health. It is the canary in the coal mine, “the ambassador for urban conservation,” and its success—or lack of it—reflects how suitable our cities are for wildlife.

“India is one of the most rapidly growing countries in the world,” he says. “Most of the population in the coming years is going to be concentrated in urban locations or cities. Now imagine cities of
tomorrow that are devoid of nature, devoid of sparrows and other birds.

“A common man in India, from when he is born to the time he dies, might not go outside the city. There are a lot of people in India who find it difficult to get two square meals a day, so you can't expect those people to spend a fortune to go to a national park to see a tiger. For such a population, the sparrow and other birds that stay in urban locations are the only connection between humanity and wildlife.”

Mohammed's campaign has made waves.
Time
magazine even named him one of the world's foremost environmental heroes. But many challenges remain.