Infrared Thermal Cameras Can Target A Poacher — But So Can Old-Fashioned Legwork : Goats and Soda Infrared thermal cameras have revolutionized the way rangers can see into the dark. But sometimes, experience trumps technology.
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Stalking Poachers With High-Tech Cameras And Old-Fashioned Smarts

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Stalking Poachers With High-Tech Cameras And Old-Fashioned Smarts

Stalking Poachers With High-Tech Cameras And Old-Fashioned Smarts

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We're about to hear from a stealthy battlefield on the African savanna, where poachers stalk their prey and they, in turn, are stalked by rangers. Now, those rangers have the kind of technology pioneered by militaries. NPR's Gregory Warner takes us on a night patrol in the Kenyan Masai Mara.

GREGORY WARNER, BYLINE: It's dusk by the time we reach our spot on a grassy hill behind some acacia.

Is that thing heavy? It looks pretty heavy.

MARTINE CHERUIYOT: Yeah, it's heavy.

WARNER: Park ranger Martine Cheruiyot hoists a 20-pound grey tube and screws it on top of our jeep. It looks less like a camera-camera, more like an X-ray machine in a dentist office. But this giant can read thermal ways. It sees a person's body heat one mile away.

CHERUIYOT: So we have just set it.

WARNER: Another camouflaged ranger rolls canvas over the windshield to block any light from revealing our position. Cheruiyot and a colleague huddle in the front seat over a grey monitor.

Oh, my. That's amazing.

And scores of white dots suddenly appear on the screen, each dot smaller than the shoe on a Barbie.

UNIDENTIFIED RANGER #1: Yeah the white dots - so you're able to know that this is a zebra, this is what...

WARNER: Oh, is that an elephant?

CHERUIYOT: This is a zebra, yeah?

WARNER: Oh, that's a zebra.

CHERUIYOT: Yeah, because of the posture.

WARNER: By the posture, he can distinguish a set of pixels that's a Thompson's gazelle from another that's a Grant's gazelle. He pan the camera right, then left with a joystick and then suddenly stops and whispers into Swahili.

CHERUIYOT: (Speaking Swahili).

WARNER: "Do you see? Is that a person?" he says. He fingers a faint, grey dot moving purposely across the screen. It's the steady movement more than the shape that alerts him. Animals meander.

CHERUIYOT: (Speaking Swahili).

WARNER: He radios the rangers in the other jeep. The grey dot, though, is already moving quickly out of camera range.

CHERUIYOT: (Speaking Swahili).

WARNER: Poachers here in the Masai Mara are usually hunting for game meat to sell, not killing elephants for ivory. They carry knives, not guns, which means that they have to sneak up so quietly on a skittish impala in the dark that they can startle it with a flashlight and then stab it with a knife. Brian Heath, the director of the Mara Conservancy says his rangers have to be even stealthier to nab the poachers.

BRIAN HEATH: Yeah. I mean, you've got to be really, really, really close to them to be able catch them.

WARNER: Because they are faster than you?

HEATH: Yeah. I mean, they're not encumbered with boots and jackets and guns. And, you know, they just drop everything and run.

WARNER: The infrared thermal camera that Heath is testing here has revolutionized the way that rangers can see into the darkness. But after one hour of quiet stakeout and then a second hour and then a third and a fourth, our one-mile radius of enhanced vision starts to feel tiny in the 600-mile park. I should should mention that there is a smaller park in Kenya that's also part of this beta test, where multiple cameras have been fixed on poles. And a team at World Wildlife Fund has even designed an algorithm to distinguish the animals from humans - a kind of poacher alarm system. It's all funded, like this enterprise, by a grant from And yet, in our fifth hour of stakeout, the radio finally squawks to life. The dark savanna goes bright with headlights. And it turns out this other team, the team without our fancy camera - that's the one that brings in the two poachers without our help.

UNIDENTIFIED RANGER #2: (Speaking Swahili).

UNIDENTIFIED RANGER #3: (Speaking Swahili).

WARNER: What did they kill? Impalas - three of them - and a Thompson gazelle. The carcasses are placed as evidenced next to the two handcuffed men. They're young guys - both 20 years old.

UNIDENTIFIED RANGER #4: (Speaking Swahili).

WARNER: "What's your name," says the ranger.

JACKSON MAIRI: Jackson Mairi.

WARNER: Jackson Mairi is shivering. He's soaking wet. He tried to hide from the rangers in a hippo pool. Ranger Patrick Gilai says his team tracked them on foot, in the dark, in the woods for more than an hour.

PATRICK GILAI: We keenly hear them. Where are they? They're here. Then we go slowly by slowly until we attack and arrest them.

WARNER: Did you use any gadgets, any technology, or just your ears?

GILAI: Our technology is just on ambushing them. You know, we have a lot of experience.

WARNER: This night, it wasn't the camera technology that triumphed, but a lifetime of skills and a lot of patience. Gregory Warner, NPR News, Masai Mara, Kenya.

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