SALMON, Idaho (Reuters) - Public outrage prompted a temporary stay of execution on Wednesday for 300 bison, including an estimated 100 calves, roaming in Montana outside the confines of Yellowstone National Park.

Three wild bison bulls are seen in Colorado March 17, 2007. Public outrage prompted a temporary stay of execution on Wednesday for 300 bison, including an estimated 100 calves, roaming in Montana outside the confines of Yellowstone National Park. REUTERS/Rick Wilking

The Montana Board of Livestock on Tuesday announced plans to capture and kill the bison, or buffalo, in the wake of news earlier this month that seven Montana cows had tested positive for brucellosis, a disease that can cause stillbirths in cows and infects some of the Yellowstone bison herd.

Bison advocates, including the Buffalo Field Campaign, launched an opposition campaign that caused an e-mail and telephone backlog at the state and federal agencies that manage Yellowstone’s 3,900 bison.

“We’ve been getting the calls,” said Christian Mackay, executive officer with the Montana Department of Livestock. But “capture and hauling to slaughter is by no means off the table.”

The department said it would delay plans to round up and kill the bison until early next week.

The proposal comes as the tourist season is under way at Yellowstone, where bison draw hundreds of thousands of admirers. Under a controversial state-federal agreement, bison that leave the protection of Yellowstone are subject to hazing and to slaughter. The department had recently tried to encourage the wayward buffalo to return to the park.

While officials have yet to pinpoint the source of the brucellosis infection in the seven cows, and there is no documented case of brucellosis transmission from bison to cows in the wild, Montana’s influential cattle industry is calling for a forced thinning of Yellowstone bison.

Cattle producers say the herd is an imminent threat to Montana’s brucellosis-free status, which allows ranchers to ship cows across state lines without testing. The state has a $1 billion livestock industry.

Animal activists say a historic prejudice against the buffalo, which were hunted and killed to near extinction by the late 19th century, continues to threaten the nation’s last wild herd of purebred bison.

Plans to forcibly thin the Yellowstone herd comes even as the U.S. Fish and Wildlife Service has proposed allowing hunters to kill more than half the bison in the National Elk Refuge in Wyoming -- reducing the herd from 1,100 to 500 animals -- because of overgrazing, concerns about brucellosis and federal budget cuts.