The spring hazing of bison on the west side of Yellowstone National Park aimed at minimizing the potential spread of brucellosis from bison to cattle. But it has caused some humans to lock horns.Conservation groups decry the federally-funded hazing, but the Montana Stockgrowers Association says hazing is necessary to thwart potential brucellosis infection in cattle.

The Interagency Bison Management Plan is administered through a partnership between the National Park Service, U.S. Department of Agriculture, Montana Department of Livestock and Montana Fish, Wildlife and Parks Department. The plan's stated objective is to maintain a free-roaming bison herd while reducing the risk of brucellosis transmission from bison to cattle.

Bison migrate out of the park in search of grass and calving grounds.

There are two or three cattle grazing allotments in the Hebgen Lake area. Those in the Horse Butte area, near Hebgen and west of Yellowstone, were retired by the U.S. Forest Service because it wasn't used to run cattle, said Matthew Skoglund, Natural Resources Defense Council wildlife advocate.

“In the Hebgen Basin, you're talking about very few cattle,” Skoglund said.

On May 14, Harlan LaFontaine, tribal member of Sisseton Wahpeto Sioux of South Dakota, sat in front of the Buffalo Field Campaign headquarters a few miles west of Yellowstone National Park. Straddling a tree stump, LaFontaine had a breathtaking view of Hebgen Lake and the gleaming, snow-clad mountains.

LaFontaine is a liaison between tribes and Campaign, a bison advocacy group.

By pressuring Congress, Native American tribes now are at the forefront of the Interagency Bison Management Plan, LaFontaine said.

Bison may be greatly diminished, but at least the tribes can influence the animal's future, LaFontaine said.

Although buffalo roamed from central Alaska to Mexico, they were nearly wiped out by the early 1900s. Bison hampered Manifest Destiny — the belief that people of western European descent had a God-given right to tame the American West, said Keith Aune, senior conservation scientist for the Wildlife Conservation Society May 12.

By 1905, with only 1,000 bison left, President Theodore Roosevelt and George Bird Grinnell founded the American Bison Society, Aune said.

Today there are roughly 20,500 bison in conservation herds managed by the government or non-governmental groups, Aune said.

Most of the conservation herds run around 1,000 head, which makes it difficult to preserve a sturdy gene pool.

“That's solid science,” Aune said.

In fact, some of the conservation bison share genes with domestic cattle, Aune said.

In 2006, there were around 5,000 bison in Yellowstone, Aune said.

“They're more or less ecologically extinct,” Aune said. “We've not recovered the species.”

Today Yellowstone Park has around 3,000 bison, said Stephany Seay, media and outreach for the Campaign.

Yellowstone bison are genetically pure. They have no cattle genes, Skoglund said.

“These are the cream of the crop,” he said.

Bison have been migrating for thousands of years, but now they are hemmed in by Yellowstone or pushed back when they depart the park in search of grass, LaFontaine said.

The livestock industry in Montana is powerful, he said.

“If money drives things, then they're the drivers ... It's the DOL (Montana Department of Livestock) that are calling the shots,” LaFontaine said.

A change in the bison management plan is needed, he said.

The Department of Livestock emphasizes sustaining the generations of ranchers in Montana, but LaFontaine wants Native Americans sustained too.

“We're talking about the life of a people,” LaFontaine said.

Ranchers have been raising cattle in Montana since the 1870s, said Errol Rice, executive vice president of the Montana Stockgrowers Association.

Reared by a ranching family himself, Rice said he is not a bison expert, but a proponent of ranch families. His goal is to market healthy, environmentally-friendly beef and preserve viable family ranch operations.

Although there have been no documented cases of bison transmitting brucellosis to cattle in the natural environment, it did occur in 1973 under a controlled setting. Research and science proves it could happen in a natural setting, Rice said. Ranching families don't hate bison; they simply believe the animals should be managed, he said.

May 15 was the deadline to drive the bison back to Yellowstone.

“There is no reason for the DOL to haze the buffalo out of here,” said Stan Cook of Horse Butte Neighbors of Buffalo, a neighborhood bison-watch group.

The Horse Butte Neighbors of Buffalo love their bison.

“Today, my heart was breaking, said group member Karrie Taggert.