It sounds like a horror story: Every few years, usually in the winter months, residents of the town of Leesburg, Va., come home from work to find their backyards overrun with turkey vultures. Not just a few birds, but hundreds of them. Everywhere.
Lt. Jeff Dube is with the town's police department. For a whole week, he spent every evening driving around town, looking for the latest vulture hotspots.
"They like Leesburg. There's really no rhyme or reason. Every three to five years they come back en mass, like this year, 2- to 300," Dube says.
They can cause a big disturbance to daily life, but not because the ugly birds make noise or claw things.
Since vultures eat rotting meat, they need very strong stomach acid to kill all that bacteria they ingest with their meal. The final digested product has to go somewhere, like your garden, car or house, where family pets or small children can get into it.
"And it smells really bad, too," Dube says.
But the Leesburg residents and police can't get rid of the vultures on their own. The raptors are covered under the Migratory Bird Treaty Act, which means that Dube has to call in the United States Department of Agriculture to do the job.
USDA wildlife specialist Chad Forehand drives around town in his white truck with Dube, implementing the official harassment techniques. They have a two-pronged attack plan for Leesburg: scare the vultures out of the trees with fireworks and then encourage them to stay away by hanging a dead vulture in the roosting area.
"It's a pretty strong visual statement when they fly back and see one of their own hanging there. They're not going to want to stick around," Dube says.
For Leesburg resident John Camp, that's a good thing. The house where he's lived for 21 years also happens to be home base for the vulture swarm.
Luckily, Camp doesn't have any vultures in his backyard anymore. At least, not any live vultures. A tall tree in Camp's backyard now hosts one of the vulture effigies.
The methods apparently work. Toward the end of the week, only one solitary vulture circled in the rainy, grey sky.
As it circles lower and lower over the rooftops, searching for a landing spot, Forehand pulls out a little starter pistol and loads in a little firecracker. The loud noise scares the vulture. It flaps away and is gone even before streak of smoke from the screamer dissipates.
With 200 vultures in one Virginia town, it's easy to think that the birds are thriving. But scientist Yula Kapetanakos, who studies vultures at the Cornell Lab of Ornithology, isn't so sure.
"There's really a lot we don't know about these birds," she says. "There have been varying estimates of how many individuals there are of black vultures and turkey vultures, which are only two of the seven species found in the new world."
Kapetanakos says part of the problem is that vultures are just really difficult to keep track of. Vulture feeding sites are too frenzied to get a reliable count of individual birds, and they are hard to catch and tag with tracking devices.
They may be ugly and smelly, but Forehand of the USDA says they are important players in a healthy ecosystem.
"They're the scavengers that are cleaning up a lot, and that's very important," he says. "They just need to sleep elsewhere, instead of here, and everything would be perfect."
Perfectly vulture-free. That is, until next time.
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