A group of bison graze in Yellowstone National Park near Gardiner, Mont. The park is trying to reduce the number of animals that migrate annually into Montana.Ted S. Warren/The Associated Press
The Blackfoot word "Eeneewah" is usually translated as bison in English. But to James St. Goddard, spiritual leader of the Blackfoot Confederacy, it means much more.
"It means everything in our language. It goes back 40,000 years, that single word," he said. "The buffalo were everything to our people: our shelter, our food, they were our spiritual brothers."
One of the last genetically pure bison herds, whose direct ancestors once thundered across the Western plains in the millions, has been reduced to a small group tucked away in the confines of Yellowstone National Park. On Monday, the herd was set to become smaller still, with the start of a controversial cull that seeks to eliminate 900 animals – 18 per cent of the population in the park – by April.
"Every time a buffalo goes down, I feel it," Mr. St. Goddard says.
The cull is part of the Interagency Bison Management Plan, which was introduced in 2000 to deal with escalating bison numbers and the threat of a disease called brucellosis. The plan calls for the number of bison in the park to be capped at 3,000; there were 4,900 in Yellowstone in the summer of 2015.
For centuries, the animals have come down from the mountains in Yellowstone National Park and travelled north from Wyoming nearly 100 kilometres into Montana to graze, especially during hard winters when food is scarce.
It's this migration that's at the heart of a conflict that pits a coalition of conservationists and indigenous people against ranchers. The National Park Service, which oversees the management of bison populations and is legally mandated to control its growth, is caught in the middle.
On the one side are those who argue the bison pose competition to cattle – valuable livestock in Montana. They also fear bison could transfer brucellosis to cows, which can trigger spontaneous abortions.
Stephany Seay, from animal advocacy group Buffalo Field Campaign, believes disease is just a convenient argument and the fight is really about money.
"It's not about brucellosis, it's about grass and who gets to eat it," Ms. Seay said. "The livestock industry views bison as a direct competitor."
Ms. Seay's group wants the animals to be federally protected and the slaughter to stop.
She said there's never been a documented occurrence of the transmission of brucellosis to cattle outside a laboratory setting. Rick Wallen, Yellowstone's wildlife biologist for the bison management program, says while that's true, there's still a potential risk of transmission.
One hundred years ago, there were only about two dozen bison left in Yellowstone, which led to conservation plans to rehabilitate the population. Today, they're one of the last remaining herds on the continent to have a pure gene pool; most bison are inter-bred with cattle.
"This is probably the most important bison population on the continent," Mr. Wallen said, "but we don't totally recognize that it's the last and best place for wild bison."
Bill Hoppe, whose 10,000-acre ranch in the Gardiner Basin sits in the path of the bison migration, says the animals' erratic behaviour has cost him personally. He got rid of his cattle stock three years ago, believing the risks of them catching the brucellosis from bison were too high.
"When they come across the park line and live in my yard, we're supposed to be more tolerant, we're supposed to live with them," he said. "On winters that are tough, I've had 200 to 300 at a time in my place here; they tear down the fences, tear up the trees. I lost three horses that were gored years ago – that's not fair. Somebody should be liable for the damages."
Already this year, about 350 bison have been culled by hunters. Another 500 animals will be rounded up by park rangers and placed in holding pens, then restrained in a "squeeze chute." Blood samples are taken to test for the prevalence of brucellosis in the herds – roughly half of all Yellowstone bison are infected – and then both healthy and diseased animals are sent to slaughterhouses and turned into food.
The plan is based off a Montana law which places the department of livestock in charge of wild migratory bison when they enter the state, said Ms. Seay. She believes the law must be repealed.
"We shouldn't have the department of livestock in charge of any wildlife species," she said, "and we need to scrap the Interagency Bison Management Plan and simply manage wild bison like any other wildlife species."
She believes there's enough land in Montana to sustain migrating herds. "The habitat's there," she said. "We just need to change the politics."
Montana has taken strides to better accommodate bison. While Governor Steve Bullock doesn't oppose the aims of the cull, he opted to allow migrating bison to "occupy suitable habitat in Montana outside of the park," according to a press release in December. This area, known as Horse Butte, will be accessible year-round to bison. On Thursday, Mr. Bullock will be celebrated for his efforts by indigenous leaders and wild-bison advocates.
Yellowstone wants to develop a "quarantine program" that could spare uninfected bison from being shipped to the slaughterhouse.
"All the animals that test negative for brucellosis exposure would stay at Stephens Creek and they would not go to the slaughter plant," said Mr. Wallen. Stephens Creek is a capture facility located in Yellowstone.
The BFC is currently advocating against such a program, believing the plan will "domesticate" the bison rather than reintroduce them into the wild.
"It's more buffalo behind fences," Ms. Seay said. "Trucking them, raising them like livestock is not wildlife restoration – that's a toxic mimic of restoration."