Technology enabling virtual fences for pets is now being adapted for livestock. Ranchers near Yellowstone National Park are testing its ability to keep cows safe from grizzly bear attacks.
JUANA SUMMERS, HOST:
As the number of grizzly bears in and around Yellowstone National Park has grown, ranchers say the bears are killing a lot more of their livestock. Some are adopting a technological solution – GPS collars for their cattle. The Mountain West News Bureau’s Hanna Merzbach explains.
(SOUNDBITE OF COWS MOOING)
HANNA MERZBACH, BYLINE: Ben Anson manages the historic Pitchfork Ranch, an hour and a half east of Yellowstone National Park.
(SOUNDBITE OF COW MOOING)
MERZBACH: He says he’s used to being able to keep track of all the grizzly bears that pass through his ranch.
BEN ANSON: I was seeing, you know, 12 individual bears in a year, and then 16 and then 20.
MERZBACH: Anson paints a picture of bears spilling out of the towering snow-dotted mountains and gobbling up calves like cheeseburgers.
ANSON: Finally, within, like, probably the last three years, I can’t really even keep track of individual bears that I see in a year.
MERZBACH: Grizzlies have been protected by the Endangered Species Act since the 1970s, meaning they can’t be hunted.
ANSON: I’ve watched bears try to eat calves out of cows as they were being born. You know, the way the rules are right now, I really can’t do anything about it besides try to haze that bear.
(SOUNDBITE OF METAL FENCING CLATTERING)
MERZBACH: Until now. Today, Anson funnels hundreds of cattle through a head gate and wrestles solar powered GPS collars from New Zealand onto them. The collars allow ranchers to track every single cow in real time on a phone app and quickly draw virtual fences to keep them away from where predators have been seen or reported.
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MERZBACH: Similar to electric dog collars, the cows will hear a beep and feel vibrations when they approach the invisible fence line. If they don’t turn back, they’ll get a small shock, which some animal welfare groups are concerned about. Those studies show cattle can adapt quickly to avoid the shock.
ANSON: If I see a cow off by herself and she’s been there for three days, there’s something that went wrong there, and that’s something I can go then investigate.
MERZBACH: In grizzly country, it’s important to remove dead livestock quickly because carcasses can attract bears. Ranchers here can also be reimbursed by the state for confirmed predator kills. And the collars help with that, too. To Amaroq Weiss, with the Center for Biological Diversity, the collars make sense.
AMAROQ WEISS: I think it has a lot of positives.
MERZBACH: Her conservation group often has different ideas than ranchers about livestock coexisting with grizzly bears. The collars are a new tactic.
WEISS: We’re so often trying to change predator behavior. If what we can do is change human behavior, how we’re managing our lives, our livestock, our pets, our footprint on the land, we’re actually going to have a lot greater success in coexisting.
MERZBACH: When grizzlies attack livestock, they can legally be killed by wildlife managers. That means, Weiss says, that while only a fraction of cattle deaths nationwide are because of predators, a lot of grizzlies around Yellowstone end up dead.
(SOUNDBITE OF COWS MOOING)
MERZBACH: In a corral at Pitchfork Ranch, the once riled-up cows are now huddled together with the collars dangling from their necks. Each pops up as a blue dot on Anson’s iPhone.
ANSON: And then if you zoom in on them, you can click on them, see which animal it is.
MERZBACH: GPS collars can be expensive. At Anson’s ranch, they cost about $50,000 to get going, plus tens of thousands more in subscriptions each year. But conservation groups are helping pay for them and funding research on their effectiveness in reducing conflicts with predators.
For NPR News, I’m Hanna Merzbach in northwest Wyoming.
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