Yellowstone Draft EIS regarding brucellosis in bison is under debate

Jul 9, 2010

Those supporting or opposing a plan to vaccinate Yellowstone National Park’s bison against brucellosis have until July 26 to comment on the National Park Service’s Draft Environmental Impact Statement (EIS) that proposes to do so by using compressed air rifles to fire darts at the wild buffalo without handling or capturing them.

Many Montanans who attended public hearings about the Draft EIS at Bozeman, Helena and Malta in mid-June expressed skepticism about the plan, questioning how it would benefit the bison or prevent the spread of the infectious disease that causes cattle, elk and bison to spontaneously abort their calves.

Yellowstone National Park biologists estimate using vaccine darts on the cows and calves as part of the 2000 Interagency Bison Management Plan could reduce brucellosis, or Bang’s disease, among bison by 66 percent, making them less of a threat to livestock herds north of Yellowstone where they often migrate. Part of the Draft EIS raises the possibility that an imperfect vaccine could make the disease more virulent. The vaccine— SRB51—has been developed for use in cattle.

Officials have said the vaccine is not 100 percent effective and not all Yellowstone bison would be vaccinated under the $300,000-a-year program that would cost $9 million in 30 years and might protect only 25 percent of the bison. There have been no documented cases of wild bison transmitting brucellosis to cattle. About 3,000 bison are estimated to be roaming Yellowstone National Park. More than 3,000 Yellowstone bison have been killed the past decade to prevent the disease’s spread.

Yellowstone now gives vaccinations by hand to some calves captured along the park’s northern border, but over the past 10 years, fewer than 200 shots have been given. Under the most aggressive of the National Park Service’s proposed plans, between 600 and 800 vaccines may be used each year.

In addition to aborted calves, brucellosis can cause infertility, decreased milk production, retained placentas and weight loss in cattle, elk, deer, bison, goats, sheep and horses. Sanitary practices in slaughterhouses and milk pasteurization prevent nearly all human cases of brucellosis, which can cause undulant fever.

As of March 1, all U.S. states were classified as free of brucellosis although seven cows in a Rigby, ID, herd that has been quarantined tested positive for it. Montana regained its brucellosis-free status last summer after brucellosis was found in herds near Yellowstone in 2007 and 2008.

Yellowstone is home to the last free-ranging herd of pure Plains bison. It’s been estimated that between 40 percent and 60 percent of the bison have been exposed to brucellosis. “Vaccinating wild buffalo is an ill-conceived, harmful, costly and wasteful plan by Yellowstone National Park that jeopardizes America’s last wild buffalo,” the Buffalo Field Campaign, an environmental group based in West Yellowstone, MT, states on its website.

Montana cattlemen support a bison management plan administered by the Montana Department of Livestock. They oppose the bison wandering outside Yellowstone’s boundaries for fear they will spread brucellosis among their cattle herds.— Mark Mendiola, WLJ Correspondent