Millions of bison used to roam the west but by the early 1900's, only a couple dozen were left inside Yellowstone. That's because the animal was over-hunted by western settlers. Yellowstone Chris Geremia, the Yellowstone National Park bison coordinator, said decades were spent to recover the population.
"As the population grew through the 20th century, they relearned migration routes that were lost," he said.
During late winter when the snow piles up, bison follow two large rivers to lower elevation areas in Montana where several ranches are located which is a problem. That's because 50 percent of the general bison population is infected with brucellosis.
Montana State Veterinarian Martin Zulaski said brucellosis causes cattle, elk and bison to not be able to give birth. The disease can be passed within the herd and between other species, though not humans.
"When elk and cattle or when bison and cattle share the same landscape during the kind of late pregnancy stage there's a potential for an effective animal typically an elk but potentially a bison to abort," said Zulaski. "And then contaminate that ground on which a cow may feed."
If cattle are infected with brucellosis, Jay Bodner, the Montana Stockgrowers Association executive director, said it could be an economic disaster for the state. That's because people can get the disease by coming in contact with it, which means brucellosis contaminated meat can't be sold.
"If those borders were to be shut off, and nobody was to purchase those calves, people would have just went out of business," said Bodner. "Because there would have been nowhere for that livestock to go. It would have been very restricted. We would have got extremely low prices for the cows or the animals that were purchased."
That's why Montana sued Yellowstone National Park back in the 1990's to stop bison from migrating out of the park with the chance of transmitting brucellosis to their cattle. It's worth noting though that there have been documented cases of wild elk infecting cattle with the disease. While there has been no documented cases of wild bison infecting cattle.
Still an eventual compromise was reached with the creation of the Interagency Bison Management Plan (IBMP), which includes state, federal and tribal agencies. Yellowstone Bison coordinator Chris Geremia said the goal is to maintain a wild, free-ranging bison population of around 3,000 in the park and to reduce the risk of any possible brucellosis transmission from bison to cattle.
"That was largely done by rounding up animals as they tried to exit the park and sending them to slaughter," he said.
Geremia said, for many years, bison stakeholders had been asking the park to find an alternative to sending animals to slaughter. A major barrier to finding an alternative is that, due to trade restrictions, a brucellosis-infected animal cannot be transported across state and federal boundaries.
"Because of this disease, we needed to find a way to first certify them as brucellosis free and that is the purpose of the quarantine program," he said. "And then if you can certify them as brucellosis free, they can be transferred to new areas to new homes to start new populations."
The quarantine program was approved by all the parties involved but as with anything there were some hiccups. In March of 2018, some bison in the program were illegally released. They were eventually recaptured but it led to restarting their quarantine. In September of the same year, the former superintendent of Yellowstone was pushed out from his position — some say because of his support of the quarantine program.
For Geremia, it's all about the different stakeholders working together towards the same ultimate goal: bison conservation.
"It takes building and continuing this relationship with the Fort Peck Tribes who have really been the tribe to work with us from day one."
The Fort Peck Tribes were vital in making the quarantine program happen by finding homes for these bison - mostly to other tribes. Like the 16 tribes that just received bison from the first successful quarantine.
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