SUN VALLEY, Idaho — Coming across a dead cow in the herd with no outward signs of what killed her often leaves cattlemen guessing about the cause.
But they shouldn’t assume it was poison, bloat, a broken neck or that she got stuck on her back. Her death could have been caused by a wolf, Todd Grimm, Idaho state director of USDA Wildlife Services, said during the Idaho Cattle Association annual convention.
A wolf’s teeth are blunt and not meant to rip, puncture or tear; they’re meant to crush muscle. Because of their thick hides, a significant majority of dead adult cattle killed by wolves show no outward sign. But they do show subcutaneous hemorrhaging and bite marks under the hide, he said.
Those clues can help investigators confirm a wolf depredation — but only if cattlemen report the death. The agency is urging cattlemen to report all deaths and to leave the carcass undisturbed to preserve the evidence.
In the past 22 years, the agency has confirmed 750 wolf depredations in cattle, affecting 400 producers in 32 counties in Idaho. But deaths from wolves are likely much higher, he said, adding that the science says that for every kill confirmed, there are probably six or seven more.
The agency needs additional data to take to the predator control board to show the problem is bigger than estimated to ease the restrictions it faces on wolf removal.
And it’s had success in doing that in the McCall zone, a chronic depredation area, where ranchers have responded to the agency’s request to report all livestock deaths.
This year, the agency has confirmed 70 wolf depredations of cattle in the region, compared to 32 in 2016. The increase in confirmed deaths is not just from more wolf activity, but also from the agency paying more attention and ranchers calling the agency to look at every carcass, Grimm said.
“We realize there are a lot more kills that cattleman aren’t identifying,” said Greg Jones, a trapper-gunner with USDA Wildlife Services.
The agency has found many of those mysterious deaths show signs of exertional myopathy, which could be caused by the stress of being chased by a wolf.
It’s found dead cows with grass or dirt pushed up in their nostrils, indicating a face plant. Other signs are animals with nose in legs out, buckled hoofs, legs straight out and no ground disturbances around the carcass, which would signify a struggle — such as being stuck in the mud or trying to get up.
“She’s dead on her feet before she hits the ground,” he said.
While there might be no external signs of a wolf attack, investigators can skin the carcass to look for subcutaneous hemorrhaging with associated bite marks that can confirm wolf depredation.
If ranchers find a dead animal, the agency wants to look at it, he said.
“We need to look at it so we can confirm. If you see something, don’t just run on by,” he said.
The only way to reduce wolf depredation is to remove more wolves, and the agency needs the data to do that, he said.
Increased depredations in chronic areas have led the agency to look at more animals it can confirm, and myopathy is playing a part, Grimm said.
“The bottom line is it doesn’t cost anybody any time or money to have us come out and look at it at the least,” he said.
Even if it’s in backcountry, cattlemen can report the death and GPS coordinates of a dead animal and the agency will investigate. It has also been able to confirm wolf depredation on scavenged carcasses, he said.