Crisis for Yellowstone's Buffalo

Bison often graze outside the boundaries of Yellowstone during the winter but are forced back in the spring with sometimes deadly tactics. Credit: John Good

Every winter, many of the bison that live in Yellowstone National Park -- the nation's last wild, free-roaming herd -- leave the park's boundaries to find food and better places to give birth and raise their young. In the spring, some of these bison, along with their newborns, get "hazed" back into park territory by rangers and wildlife agents swooping down in helicopters, on horseback and riding ATVs.

Hazing is disruptive and devastating to the bison -- more commonly called buffalo -- and to other wildlife and humans in the area. Some bison, including newborns, are needlessly killed in the process. Others are captured and slaughtered.

Why is it happening?

Buffalo can carry a disease called brucellosis. Ranchers in Montana worry that if the buffalo leave Yellowstone's boundaries, they might pass the disease to their cattle. 

But their worries have no basis in reality. There are no documented cases of brucellosis ever being transmitted from wild buffalo to cattle -- and furthermore, some areas outside of the park that bison favor, such as the lush Horse Butte peninsula, are free of cattle year-round.

Why does it matter?

Wild bison have played an integral role in the ecology, culture and history of the American West. The iconic animals were central to the lives and religion of Native American tribes. In the early 19th century, 60 million buffalo roamed the Great Plains, but by the mid-1890s, fewer than two dozen remained.

Today, the herd that makes its home in Yellowstone National Park comprises the largest remaining population of genetically pure bison. The vast majority of bison left in North American have intermingled with cattle and carry their genes. Yellowstone's bison do not, making them critically important for the conversation of the species.

Despite that, state and wildlife officials killed about 1,600 of Yellowstone's bison herd in 2008, leaving more dead in one year than at any time since the great slaughters of the 19th century. Severe winter conditions and a late spring resulted in the death of hundreds more animals. All told, about a third of Yellowstone's buffalo population perished in 2008.

Despite the massive death toll and the potential for another senseless slaughter, the government began hazing again in 2009 and has shown no signs of stopping.

What can be done?

The Department of Agriculture could put a stop to the hazing and senseless deaths of Yellowstone's buffalo herd. Take action at NRDC's Save BioGems site by sending a message to the Secretary of Agriculture and urging him to protect these threatened wild animals.