JACKI LYDEN, HOST:
Thanks for tuning in. This is WEEKENDS on ALL THINGS CONSIDERED from NPR News. I'm Jacki Lyden.
It sounds like a horror story. Every few years, usually in the winter months, residents of the town of Leesburg, Virginia, come home from work to find their backyards overrun with turkey vultures. Not just a few birds, but hundreds of them. Everywhere.
NPR's Liz Baker went to Leesburg to check it out.
LIZ BAKER, BYLINE: Lieutenant Jeff Dube is with the town of Leesburg's police department. Tonight, like every night this week, he's dispatched on a special project, driving out to the huge flock of vultures that has taken over town.
LIEUTENANT JEFF DUBE: They like Leesburg. There's really no rhyme or reason. Every three to five years, they come back en mass like they did this year, two to 300.
BAKER: As you can imagine, two to 300 vultures cause a lot of damage.
DUBE: They defecate on the houses, cars. And it's very acidic. It can strip paint.
BAKER: It also kills grass and yard plants and sickens dogs, cats and young children who get into it.
DUBE: And it smells really bad too.
BAKER: But Leesburg's residents can't just go out and get rid of the vultures on their own. The raptors are covered under the Migratory Bird Treaty Act. So bothering the birds is illegal unless you're with the U.S. Department of Agriculture. Dube explains.
DUBE: That's when we have to call in the professionals, the USDA, to come in because they're authorized to perform the harassment techniques.
BAKER: That's right, harassment techniques. There are two tried-and-true methods for getting rid of vultures. One is shooting loud fireworks at them, and the other - and this will sound a little strange - is hanging a dead vulture from a tree. Tonight, USDA Wildlife Specialist Chad Forehand is on vulture duty.
CHAD FOREHAND: And this is the place that had over about 200 birds roosting in it each night.
BAKER: Forehand brings me to a house in a quiet suburban neighborhood, home base for the vultures, and for John Camp, who has lived here for 21 years.
JOHN CAMP: I'm like in a sort of an Alfred Hitchcock movie.
CAMP: They just made a big mess back there in the backyard. And I don't want them. I don't want them.
BAKER: Tonight, there's only one vulture in Camp's yard - a dead one - put there by Forehand.
FOREHAND: It's a vulture hanging upside down. That's all it is. And that's the main reason they're not here anymore. It's a pretty strong visual statement when they fly back and they see one of their own hanging there. They're not going to want to stick around.
BAKER: Firecrackers also drive the vultures away. The loud noise scares them out of the trees. These methods clearly work. Talking with Dube out in the rain, I keep scanning the sky for the apocalyptic swarm of vultures I'd been expecting. They seem to be a no-show, but then...
I see one, I see one, I see one.
DUBE: Yup. He's trying to sneak in.
BAKER: Just a solitary vulture, but still a big, hulking presence against the grey sky. It circles lower and lower over the rooftops, searching for a landing spot.
DUBE: Yeah. They're very crafty.
(SOUNDBITE OF FIREWORKS)
BAKER: The vulture flaps away in the rain and is gone even before the smoke from the screamer dissipates.
DUBE: You can imagine if that tree was full of about 200 birds and he did that. It's an impressive sight to watch them leave.
BAKER: With 200 vultures in one Virginia town, it's easy to think that the birds are thriving. But scientists aren't so sure.
YULA KAPETANAKOS: There's really a lot that we just don't know about these birds.
BAKER: Yula Kapetanakos studies vultures at the Cornell Lab of Ornithology.
KAPETANAKOS: There's been varying estimates even as to how many individuals there are of turkey vultures and black vultures, which are only two of the seven species that are found in the new world.
BAKER: Kapetanakos says part of the problem is that vultures are just really difficult to keep track of. And they have much better eyesight than humans, so they're very hard to catch and tag with tracking devices.
KAPETANAKOS: And so when their populations start to decline, it can often take us by surprise.
BAKER: Kapetanakos has a project to track vultures by collecting feathers left behind at feeding sites. She uses the DNA to tell which individual bird has been where. But with so little information out there about turkey vultures, it's good that USDA specialists like Chad Forehand are the only ones allowed to drive them out of town. For Forehand, the birds are important players in the ecosystem.
FOREHAND: They're the scavengers that are cleaning up a lot. That's very important. They just need to sleep elsewhere, instead of in here, and everything would be perfect.
BAKER: Perfectly vulture-free, at least for now. For NPR News, I'm Liz Baker.
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