美国国家公共电台 NPR To Decrease Bird Kills, Cat Lovers Team Up With Bird Lovers In D.C. Cat Count（在线收听）

LULU GARCIA-NAVARRO, HOST:

Herding cats - difficult. So how about counting cats? Researchers in Washington, D.C., have just begun work on a three-year, $1.5 million cat census to get a definitive count of how many cats there are in the city. But why do we even need a cat count? Jacob Fenston from member station WAMU has the answer.

JUSTIN BELSLEY: Hundred meters.

JACOB FENSTON, BYLINE: Justin Belsley is checking his GPS, navigating a densely forested part of Rock Creek Park right in the middle of Washington, D.C.

BELSLEY: It is southwest, so I guess we should take this trail.

UNIDENTIFIED PERSON #1: All right.

UNIDENTIFIED PERSON #2: OK.

FENSTON: Belsley is a field technician working on the D.C. Cat Count. He and Mike Cove are tracking outdoor cats - strays, ferals and pets - using the same methods scientists use to study much larger animals.

MIKE COVE: Tiger researchers have been doing this for two decades.

FENSTON: Setting up wildlife cameras, taking thousands of photos and using the photos to identify individual animals based on their markings.

COVE: We're doing the same thing. We're just working with much smaller tigers.

FENSTON: Cove and Belsley come from very different backgrounds, even opposing camps. Cove is a wildlife biologist who studied the negative impact feral cats can have on wildlife. And Belsley...

BELSLEY: I have fed a colony of feral cats myself for about three years now, and I just love cats.

FENSTON: For decades, there's been a passionate, often overheated debate amongst humans who love animals. It pits cat lovers, who want to help feral cats survive in the wild, against bird lovers, who say cats are causing bird populations to plummet. Dan Herrera is also working on the cat count.

DAN HERRERA: This project has kind of stoked the fire a little bit. It's, like, people who proclaim to be team cat and team bird.

FENSTON: It's not just the field techs who come from opposing teams. So do the organizations behind the project - the Humane Rescue Alliance - team cat - and the Smithsonian Conservation Biology Institute - team bird. For now, though...

HERRERA: We are team science.

FENSTON: It's a sort of truce.

(SOUNDBITE OF BIRD SQUAWKING)

FENSTON: To understand why the cat-bird debate is so heated, I head out on a bird walk with the DC Audubon Society.

DANA MCCOSKEY: So we have one of the first birds today - blue jay.

FENSTON: Dana McCoskey is one of the walk leaders. At one point between bird sightings, conversation turns to the threats facing native and migratory birds.

MCCOSKEY: A lot of people are only now understanding that their beloved cat (laughter) can be a...

UNIDENTIFIED PERSON #3: Killer.

MCCOSKEY: ...Cold-blooded killer. Yeah, and so...

FENSTON: McCoskey cites a 2013 study that found cats kill as many as 4 billion birds a year in the contiguous United States. But nobody knows how many cats are doing the killing.

BILL MCSHEA: Are there 1,000 cats out there, 10,000, 100,000?

FENSTON: The Smithsonian's Bill McShea, one of the lead researchers working on the cat count. For the past decade, D.C. has been neutering feral cats, then releasing them back into the city. The idea is that, over time, this population of sterilized cats will dwindle and disappear. Another reason we need a cat count - to see if that's actually happening.

COVE: Where do we cross?

HERRERA: So the bridge is that way.

COVE: Oh, it is that way.

FENSTON: Back in Rock Creek Park, the field technicians are heading to their next camera location.

HERRERA: I'm always really quick to show these off.

FENSTON: Dan Herrera pulls out his cellphone.

HERRERA: This is my little best-of collection - adorable, little fox there.

FENSTON: That's awesome.

COVE: Red fox.

HERRERA: There's a coyote. Yeah, a red fox.

FENSTON: In just a few weeks since they've started, they've gotten more than 40,000 images - foxes, coyotes, people walking dogs - but so far, only one cat photo - black and white, a large, well-fed feline slinking through the woods. It's way too early to draw any conclusions. Maybe the growing coyote population is keeping cats out of the wilder parts of the city, thereby protecting native birds. Or maybe D.C. cats are just extra-stealthy. For NPR News, I'm Jacob Fenston.