BILLINGS, Mont. (AP) - The Montana Department of Livestock announced plans Tuesday to study the possibility of vaccinating bison against brucellosis when they wander into the state from Yellowstone National Park.

The goal is to release an environmental assessment by late November and to have a decision by January, spokeswoman Karen Cooper said. If that timetable holds and a vaccination program is settled on, it could be implemented during the remaining winter, she said.

Public comments on such things as the efficacy and safety of available vaccines and the cost of a possible vaccination program will be accepted through July 23, the department said.

A vaccination program would be an "extension" of a joint federal-state bison management plan already in place, Cooper said. In this case, it would apply to bison that enter the state from the park's western edge and northern edge, she said.

This past winter, some bison were vaccinated near Yellowstone's northern boundary but within the park, where the National Park Service is the lead agency for management actions under the bison management plan, officials said.

The interagency bison management plan allows for hazing and capture of bison and for testing bison for brucellosis. State livestock industry officials and ranchers are concerned bison will transmit brucellosis to cattle. Bison testing positive are sent to slaughter.

The disease can cause domestic livestock to abort and infrequently causes undulant fever in humans.

"As agencies, we want to ensure we're doing everything we can do to reduce the risk of brucellosis and maintain Montana's brucellosis-free status," Cooper said.

Josh Osher of the Buffalo Field Campaign said he sees any vaccination program as a "feel good thing" for Montana officials.

"That way they can say they're doing something positive, other than killing all these bison," he said. "But if they're talking about eradicating brucellosis, vaccination is not going to get them there."

Osher also raised concerns with the efficacy of available vaccines and suggested more attention be placed on developing a more effective vaccine for cattle.

Separately, the Montana Department of Fish, Wildlife and Parks recently released a draft environmental assessment that would allow for limited hunting of bison that stray into the state. Officials have said they view a potential hunt as an extension of the bison management plan. Comments are being taken on that proposal. ---

On the Net:

Montana Department of Livestock: http://www.discoveringmontana.com/liv/

AP-WS-06-15-04 1819EDT