Where tourists visiting Yellowstone National Park see a wildlife haven for free-roaming buffalo, a cadre of federal and state scientists see a reservoir of disease that threatens to spill into the outside world.


"Yellowstone National Park is a cloud hanging over us," says Dick Rath, a veterinarian from Bozeman, Mont.


Rath and his colleagues, including state veterinarians and the federal Animal and Plant Health Inspection Service (APHIS), want to inspect Yellowstone bison herds they say could spread brucellosis, the disease that causes livestock to abort their fetuses. They are backed by Montana Sen. Conrad Burns, R, who has introduced a bill that would require the Park Service to kill disease-carrying bison in Yellowstone.


APHIS and the state veterinarians have set l998 as the target year for completely eradicating brucellosis, a virus the federal agency has been battling since l954, when European cattle introduced the disease. That's ambitious, but reachable, according to Clarence Siroky, Montana state veterinarian. "You've got to decide that you're going to solve the problem and go in there and do that," he says.


Environmentalists and park advocates are not so optimistic. "It's time that they step back and revisit that l998 goal," says Tory Taylor of the Jackson Hole Alliance For Responsible Planning. "We're all working toward it, but this idea that we can totally eradicate brucellosis is a pipe dream."


Park Service spokesman Stuart Coleman says the virus is widespread and shows up in elk, moose and a few grizzly bears. "It's in the ecosystem," he says. "It's ridiculous to address bison and not elk." He's resentful of the way the scientists have bullied the issue. "Clarence Siroky singlehandedly pushed a rock off a cliff with this brucellosis issue," says Coleman. "He's set this whole process back several years."


To Siroky, the notion that elk could carry brucellosis is nonsense: "Somebody has yet to prove if the other animals are a problem," he says. But there are no known cases of bison transferring the disease to domestic cattle, either, according to the National Park Service.


Ranchers are caught in the middle. They recognize that APHIS holds tremendous power in its ability to give states a "brucellosis-free" designation. Ranchers in states with this status, such as Montana and Wyoming, can export their cattle and avoid an expensive battery of tests and possible slaughter of infected cattle. However, on recommendation from the state veterinarians, those two states could lose their APHIS designation.


"That would be unacceptable," says Mary Mead, an area rancher. Mead says ranchers regularly vaccinate their cattle with Strain-l9, a weakened form of the virus that protects cattle from average exposure to the disease. And ranchers already cooperate with the Park Service to keep their cattle away from the roving bison herds. "We've never had problems with brucellosis," says Mead. "It would be nice to have brucellosis-free wildlife but I think that's unrealistic."


The issue has taken on added fervor with Burns' bill, which would require testing of every bison in the park, and the neutering or destruction of every animal that tested positive for the virus. The rest would be quarantined for further testing. "The National Park Service has let this problem get out of control," says Dick Wathams of Burns' staff. "Nothing seemed to be getting done."


The Burns bill has drawn opposition. "It's a sledgehammer solution," says Stuart Coleman. "The bison deserve a little better than that. This is a simplified, naive approach."


After a meeting with Wyoming conservationists, Wyoming Gov. Jim Geringer asked Burns' co-sponsor, Wyoming Sen. Craig Thomas, R, to hold off on the bill until a solution can be reached through a cooperative interagency committee.


Pam Lichtman of the Jackson Hole Alliance fears that Burns and APHIS might be shooting themselves in the foot, making life more difficult for the people they propose to help. "They're doing it for the ranchers and I think they're only going to piss them off."


* Shea Andersen, HCN intern