FEW city dwellers notice the cacophony of sirens, horns, and roaring jets that punctuates urban life. But today, more than ever, this accidental orchestra has an ear-catching new member.
Targeted by hunters and uprooted by rural development, record numbers of cawing crows are popping up in American cities, discovering such delicacies as day-old french fries.
With this change of lifestyle, these coal-black passerines join deer, bats, coyotes, and raccoons on a growing list of wild creatures that have learned to thrive amid humans.
As is usually the case, city folk are sharply divided on the merits of their new neighbors: While some consider the birds an invading army, others spend hours tossing them peanuts.
According to the North American Breeding Bird Survey, the overall crow population is rising by less than 1 percent every year. But Audubon Society estimates suggest that the number of crows in some cities has quadrupled in the last decade.
Sam Droege, an ornithologist at the National Biological Survey, says crows thrive in cities, because they have a varied diet, flexible nesting practices, and a knack for avoiding people and their bird-eating pets.
``Crows seem to fare best when they can nest in tall trees adjacent to open areas where they can forage,'' says Cynthia Parr, a doctoral student at the University of Michigan who studies crow behavior. Ms. Parr says city parks and tree-lined neighborhoods not only fill this bill, but they also provide a haven from hunters and other crow predators like hawks and great horned owls.
As urban sprawl continues, she says, ``I suspect nesting sites in the countryside are becoming a problem.''
YET some urbanites liken the influx of crows to an invasion. Homeowners complain that the birds tear up their lawns in search of grubs, ransack garbage bags and compost piles, swoop down on pedestrians, cover cars with droppings, and make an awful racket in the wee hours of the morning.
Backyard bird-watchers often condemn crows, because they prey on young songbirds like warblers and cardinals, and alter the ecological balance.
Still, some city folk have taken a shine to these distant cousins of the blue jay. Long described by scientists as one of the most intelligent of all birds, crows were once common house pets and can be taught to speak, solve puzzles, and perform tricks.
Parr says the birds can never be caught the same way twice and can count as high as six. ``If six hunters go into a blind and five come out, the crow won't be fooled,'' she says. ``It's pretty amazing.''
In fact, crow-watching has become something of a weekend pastime.
Richard Banks, a zoologist with the National Biological Survey, says he and his family spent hours at a time in Arlington, Va., last spring observing a family of American crows nesting in their backyard.
Mr. Banks says he noticed that if a crow finds a chunk of hard, dry food it cannot swallow, it will drop it in a puddle of water to soak until it becomes soft enough to chew.
``Crows respond to the environment the way we do,'' says Kevin McGowan, an ecologist at Cornell University in Ithaca, N.Y.. ``They look and ponder before doing something; they assess the situation. They're smart for a bird, I suppose. Some people feel a connection with them.'' According to Mr. McGowan, people warm to crows when they learn the birds mate for life and live together in family groups.
Many parents (especially those of recent college graduates) are interested to learn that some crows hang around for years after adolescence and often have to be thrown out of the nest, he adds.
Scientists note that the birds are remarkably social. Those who study crows during their winter roosts describe the atmosphere as ``something akin to Mardi Gras.''
Yet these cold-weather gatherings, which can include hundreds of thousands of birds, have driven some towns to take action. Kearney, Neb., sits smack in the middle of Buffalo County, an area that some ornithologists say hosts one of the largest crow roosts in North America.
The birds arrived in town in such overwhelming numbers five years ago, says John Prescott, assistant to the city manager, that the city had to scrape their droppings off sidewalks with snow removal equipment.
In an effort to persuade the birds to roost elsewhere, the city has installed in trees noisemakers and yellow balloons that resemble owls designed to discourage crows from roosting.
Mr. Prescott says the city has also issued about two dozen permits for the discharge of firearms within city limits under a city ordinance covering ``nuisance animals.''
Although groups like People for the Ethical Treatment of Animals have protested the ordinance, Prescott says it's hard to find anyone in Kearney who feels sympathetic.
Even so, Prescott says the town has no plans to resort to the most effective, if macabre, method of dispersing crows. In Cedar Rapids, Iowa, during a recent crow deluge, city officials there mounted dead crows on boards and hung them in trees to deter the birds.
``Our people in the parks and recreation department aren't real enthusiastic about that option,'' Prescott says.
Scientists are unsure whether the crows are migrating to cities or just reproducing faster in urban environs. McGowan says that, in some ways, the city is becoming less hospitable every year, as garbage collection improves. Although crow populations have increased steadily in cities for 30 years, he says urban life takes a toll on the birds.
``Crows that nest in the city tend to have smaller offspring and less of them,'' he says, ``because the food in town is not as good.''
As for the birds' enduring image problem, scientists agree that much of it stems from centuries of literary vilification at the hands of countless poets, novelists, and filmmakers.
Even Shakespeare made a few cracks about crows, including this one in ``The Merchant of Venice'': ``The crow doth sing as sweetly as the lark,'' Portia says, ``when neither is attended.''
``People don't like big black birds because they're evil looking,'' says McGowan, a frustrated fan of the birds, ``but they don't understand that without them, we'd be up to our necks in cardinals.''