BILLINGS, Mont. — For the first time in decades, the federal government is considering moving bison captured leaving Yellowstone National Park to public lands in Colorado, South Dakota and elsewhere as part of efforts to curb periodic slaughters of the animals.
However, Montana Gov. Brian Schweitzer said Wednesday the animals belong to his state and he will block any attempt to move them.
In a Tuesday letter obtained by The Associated Press, Interior Secretary Ken Salazar told Schweitzer his agency is looking at relocation sites including Badlands National Park on South Dakota's Pine Ridge Indian Reservation and Great Sand Dunes National Park in Colorado.
Salazar also mentioned Wyoming's Wind River Reservation, where a prior attempt to place Yellowstone bison collapsed two years ago.
The proposal came as state and federal officials have been trying to come up with alternatives to the periodic slaughter of bison leaving the park in search of food. Cattle ranchers say those migrations raise the chance of livestock being infected by diseased bison.
Many of Yellowstone's 3,700 bison have been exposed to the disease brucellosis, yet the animals remain prized for their pure genetics. The bison to be transferred have been tested and are considered disease-free.
"I want to work with you to manage bison numbers and reduce disease prevalence in the Yellowstone herd," Salazar wrote to Schweitzer. "While the Department of Interior alone cannot resolve this issue, I am willing to look at options of moving Yellowstone bison onto other DOI properties."
After receiving the letter, Schweitzer issued an order blocking any fish and wildlife shipments by the Interior Department in Montana. The governor wants the bison to go to the National Bison Range near Moiese in western Montana.
He said he was concerned in part that the Interior Department's past actions have allowed animal diseases such as brucellosis and chronic wasting disease to spread across the region.
"These aren't Interior's bison to decide where they go. They belong to the state of Montana," Schweitzer said Wednesday.
Wildlife officials said Wednesday the prohibition ordered by Schweitzer could effect federal trout hatcheries that produce more than a million fish annually.
No other wildlife shipments are currently planned, although Yellowstone administrators have proposed shipping brucellosis-positive bison to slaughter this year if hunting outside the park does not keep the population from outgrowing the park.
The prohibition comes after Interior officials earlier this month rebuffed Schweitzer's proposal for the bison range. They said having Yellowstone animals on the Montana range would stigmatize the bison already there and make it harder to eventually transfer the Yellowstone animals to other states that are worried about the spread of the disease.
Salazar said in his letter that the transfer of bison to Moiese had not been ruled out, but an evaluation of such a move would not be completed during the upcoming winter season.
A relocation of animals to the Great Sand Dunes could be done in partnership with a conservation group, The Nature Conservancy, that owns the Zapata Ranch adjacent to the park, Salazar said. Bison relocated to the Badlands would be managed in cooperation with the Oglala Sioux Tribe.
Yellowstone biologists have predicted that more than 1,000 bison could exit the park this winter seeking food at lower elevations.
Millions of bison once roamed North America. Most of those herds were wiped out by the late 1800s, and by 1902 only about two dozen of the animals remained in Yellowstone.
After the park's herd gained new protections and gradually rebounded, Yellowstone administrators sought to keep bison numbers in check by slaughtering the animals or shipping them elsewhere, said Keith Aune a bison biologist with the Wildlife Conservation Society.
Those shipments continued into the 1960s, ending after the park adopted a policy of regulation in which bison numbers would be controlled by natural deaths.
But the park's herds soon began spilling over its border, and thousands of those migrating animals have been captured and shipped to slaughter over the past decade to guard against livestock being infected by brucellosis. The disease can cause pregnant animals to miscarry. Ranches that suffer infections are subject to lengthy quarantines.
Schweitzer has said he will allow the state to transfer 66 disease-free Yellowstone bison to eastern Montana's Fort Peck and Fort Belknap Indian reservations.
Another 143 Yellowstone bison are being held at a ranch near Bozeman. Those are the animals that Salazar is suggesting could be sent to federal lands elsewhere. Before being put on the Turner ranch for temporary holding, the bison spent several years in a government-run quarantine near the park to ensure they were brucellosis-free.
The quarantine compound is expected to be used beginning next year to study the effectiveness of chemical contraceptives on bison. Salazar said in his letter that he has asked the National Park Service to evaluate whether a new quarantine facility should be built.
Aune said the relocation of disease-free bison captured from Yellowstone has potential to help the species recover in other parts of the country.
Garrit Voggesser, director of tribal partnerships for the National Wildlife Federation, said that could take several years to arrange, and that his organization would not endorse specific proposals.
Associated Press writer Steven Paulson contributed to this story from Denver.