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Letting the Buffalo Roam

How NRDC has fought for years to keep Yellowstone’s bison healthy—and free.

Bison grazing on Rose Creek, Lamar Valley, Yellowstone National Park Neal Herbert/NPS/Flickr

Like so many other species that we regard as iconic—from the bald eagle to the gray wolf, from the California grizzly to the Florida panther—the wild bison has had to learn the hard way that this status doesn’t automatically translate into safety.

At the dawn of the 19th century, an estimated 60 million wild bison (more commonly known as buffalo) roamed across the Great Plains, where they played an integral role in the ecology of the West and were central to the lives and religion of Native American tribes. By the end of that same century, however, fewer than two dozen remained in the wild.

Over the last hundred years, we’ve managed to bring wild bison back from the brink of extinction, but to say that these animals are now safe would be a profound overstatement. The vast majority of bison in North America have intermingled with cattle over the decades and carry their genes. However, the nearly 5,000 wild bison that currently make their home in Yellowstone National Park haven’t and don’t—which makes them some of the last living links to the original, genetically pure bison that once roamed the land. It also makes them critically important for the conservation of the species.

We’ve helped this population bounce back, but we haven’t always made it easy. And at times we’ve made it downright difficult. Every winter, for example, many of Yellowstone’s bison 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 newborn calves—get “hazed” back into park territory by government agents who swoop down on them in helicopters or chase after them on horseback or in ATVs. Some animals are killed in the process; others are sometimes captured and shipped to a slaughterhouse.

Such tactics are obviously disruptive and dangerous to the bison. But they also are unwarranted and unnecessary. As a rationale, those engaging in the hazing have cited concerns about brucellosis, a nonnative disease that some bison (as well as other animals) can carry. Some ranchers worry that if the bison leave Yellowstone’s boundaries and roam into Montana, they’ll transmit the disease to cattle.

But their worries are overblown. There are no documented cases—ever—of brucellosis having been transmitted from wild Yellowstone bison to cattle. What’s more, a number of areas outside the park that the bison typically favor, such as the lush Horse Butte peninsula, are completely free of cattle year-round. As for the small risk that does exist of bison-to-cattle transmission, scientists and wildlife managers have already come up with ways to minimize and mitigate it.

Despite these facts, state and wildlife officials killed more than 1,400 of Yellowstone’s wild bison in 2008. Along with the many more that were hunted, 2008 represented a one-year death toll that hadn’t been seen since the great slaughters of the 19th century. All told, about one-third of Yellowstone’s wild bison population perished that year.

A few years later, a diverse group of stakeholders, including NRDC, convened in search of common ground and a more sensible bison-management policy. A lot of changes in the bison-management world had occurred in the previous decade, which prompted the group to come together. The state, federal, and tribal entities that collectively manage Yellowstone’s bison population supported the coalition and provided a highly respected facilitator to help the group move forward. That group, which came to be known as the Yellowstone Bison Citizens Working Group, strove in 2011 and 2012 to provide citizen input on bison management in Montana.

One significant change, for example, came in 2010, when the federal government eased some of the stringent regulations regarding how ranchers and states should go about dealing with brucellosis. The relaxing of these rules considerably reduced the burden on cattle producers—and opened the door for more tolerance of the bison that annually make their way out of the park.

And then, two years later, came the announcement that NRDC had long been waiting for: The State of Montana was proposing that the wild bison population within Yellowstone be given significant year-round habitat outside of the park. Much debate, and numerous delays, ensued. Finally, though, Montana Governor Steve Bullock took executive action, announcing in late 2015 that the state was moving forward with establishing a year-round “tolerance” zone on the park’s western and northern edges. If the various state, federal, and Native American groups that make up the Interagency Bison Management Plan, or IBMP, formally approve the move, as they’re expected to, the results could be game changing.

“This was huge news, and it represented a major step forward both for bison management and for the state of Montana,” says NRDC’S Matt Skoglund, who directs NRDC’s Northern Rockies office. “A broad coalition of stakeholders—conservationists, hunters, landowners, bison advocates, business owners, and other concerned citizens—has been advocating for years that it was well past time to provide wild bison with year-round habitat outside the park.”

The decision, Skoglund notes, wasn’t perfect; wild bison are still at risk. In the first few days of 2016, the IBMP announced a plan to cull an outrageous 600 to 900 of the animals before the end of the winter. Their reason for doing so? A sorely outdated—and wholly unscientific—goal of getting the current population of about 4,900 down to 3,000, ostensibly for better and easier management of the herd.

“Could the state go even further with bison in Montana?” Skoglund asks. “Yes, absolutely. And we’d like them to. But that doesn’t take away from the fact that this is a watershed moment. We’ll no longer have to speculate about what bison may or may not do on this landscape that was once off-limits to them. They’ll be free to wander, year-round, on a big chunk of land. And I can’t wait to see it happen.”

The wild bison of Yellowstone are living, breathing history. To see these creatures, the largest land mammals on the North American continent, grazing on the wild and rugged Yellowstone landscape is to experience an important piece of our past — and, one hopes, our future.

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