By Laura Zuckerman
SALMON, Idaho (Reuters) - For the first time in a century, buffalo from the nation's last purebred herd will be able to roam from Yellowstone National Park into parts of Montana without facing capture and likely slaughter, based on a government agreement approved on Tuesday.
Officials with the government and tribal agencies that manage the bison said the deal ushers in a new era for the 3,700 bison that have come to symbolize the American West and which draw millions of visitors to Yellowstone - and Montana - every year.
"This is the most significant advance in recent times in tolerating bison outside Yellowstone," said Mike Lopez, attorney for the Nez Perce Tribe, one of the nine partners that manage the buffalo.
The Idaho-based American Indian tribe holds treaty rights dating from 1855 to hunt bison on public lands near the park.
The plan crafted by the federal, state and American Indian tribal governments that oversee the famed herd opens 75,000 acres of mostly public lands in Montana to buffalo whose drive for food in winter can cause them to stray from the park.
The bison have for decades been barred from Montana because they can harbor brucellosis, a bacterial infection that makes cows miscarry.
The powerful ranching industry has worried bison would endanger Montana's brucellosis-free status, which protects the market value of cattle.
But less restrictive federal rules recently adopted for brucellosis and cattle mean bison are less likely to threaten the state's disease-free standing, a key reason the Montana Department of Livestock signed off on the new agreement, officials said.
The deal comes after roughly 600 Yellowstone buffalo, or bison, were captured and corralled since February for roaming into nearby Montana.
Pat Flowers, regional supervisor with Montana Fish, Wildlife and Parks, said the extreme winter conditions in the Yellowstone area had made bison management more challenging than ever.
But a furor erupted over plans to send to slaughter bison which tested positive for exposure to brucellosis.
Amid legal wrangling and a growing divide between livestock and tourism industries, Montana Governor Brian Schweitzer in February granted some 200 buffalo a stay of execution.
But the plan to allow bison into Montana still raises concerns among ranchers, who fear the one-ton animals will damage fencing and other property.
Wildlife advocates also object to provisions of the deal that will expand hunting of some buffalo.
Systematic hunting of buffalo west of Mississippi cut their numbers from tens of millions to the fewer than 50 in the early 20th century that found refuge at Yellowstone.
(Editing by Alex Dobuzinskis and Peter Bohan)