Federal study says Yellowstone-area bison can be restored without disease risk to other livestock

The wild bison population in the area around Yellowstone National Park could be restored by using bison free of cattle disease to establish new herds without posing a risk to livestock, according to a Department of Agriculture study to be published in the next edition of the Journal of the American Veterinary Medical Association, Laura Zuckerman reports for Reuters. 

Hunting reduced the bison population in the early 20th century to "fewer than 50 that found refuge" in Yellowstone, Zuckerman writes. "Today, the more than 4,000 buffalo that roam Yellowstone are a top tourist attraction in the park, which occupies the northwestern corner of Wyoming and spills over into Idaho and Montana. But the iconic animals face capture and death when they wander beyond the park in Montana during winter in search of food."

But the Yellowstone bison face a new threat in the form of brucellosis, "an infection that can cause stillbirths in cows and was introduced to the park by domestic livestock," Zuckerman writes. "Montana's cattle industry, an influential political constituency in the state, fears that straying buffalo will transmit the illness to cows that graze near Yellowstone. That could cause Montana to lose its brucellosis-free status, which allows cattle to be shipped out of state without testing and preserves their market value." That led to a controversial federal-state management plan "that has allowed thousands to be shipped to slaughter when harsh winters lead them from the snow-covered high country to winter range in lower elevations outside the park in Montana."

For the past three years some bison have been quarantined on Native American lands in Montana and regularly tested for signs of brucellosis, Zuckerman writes. "Animal disease specialists with the USDA and a scientist from the nonprofit Wildlife Conservation Society show that culling out bison calves exposed to brucellosis can make for a disease-free herd." Keith Aune, co-author of the study, wrote, "The key conclusion is that it's feasible for us to take bison from Yellowstone and make them eligible to be used for restoration. They are a very important source of genes that harken back to the ancient DNA of North American bison." (Read more)