Yellowstone National Park's bison have come a long way since 1901, when only 44 survivors of North America's millions grazed inside its boundaries. Stu Coleman, chief of the park's natural resources branch, estimates the current population at 4,300 - nearly a hundred times that number - and calls the place "a bison-generating machine."
In 1988-89, when
Montana hunters shot 569 shaggy escapees from the park's northern
range, the news photos were gory and a national outcry was raised.
This winter looks even worse: Bison are now popping out of
Yellowstone's east and west boundaries as well, and Coleman fears
that a hard winter could drive as many as several thousand out of
the park in the coming months. By early December the death toll
already stood at 36.
Until the mid-1960s,
Yellowstone bison were culled to keep their numbers in check. Since
the National Park Service embarked on its "natural regulation"
experiment, however, the population has been exploding. Increased
winter recreation in Yellowstone has also provided hard-packed
snowmobile routes on which the animals can walk right out of the
Once they cross its boundaries, bison are
likely to find themselves on the wrong end of a state game warden's
rifle barrel whenever they approach private property or livestock.
Of major concern in the cattle-raising states around the park is
brucellosis, a disease carried by bison which can cause cattle to
abort their calves.
According to Don Bosman,
Wyoming's state veterinarian, a nation-wide brucellosis eradication
program is finally on the verge of success. Yellowstone's neighbors
- Idaho, Montana and Wyoming - have all been certified
brucellosis-free, but Bosman's Montana counterpart, Clarence
Siroky, fears that its infected wildlife (elk here are also
carriers) could cause other states to impose costly testing
requirements on cattle shipped out of the region. Ironically,
scientists generally agree that bison caught the disease from
domestic livestock in the first place.
there has never been a documented case of bison passing the
infection to cattle on the open range, Bosman notes, "absence of
proof doesn't mean that it's not happening." And Siroky fears that
as more and more bison come out of the park, it will be impossible
to keep them segregated enough from cattle to avoid contagion. He
says, "It's not a question of if, but when."
Yellowstone Park's Coleman does not agree that
"we have this pit of pestilence." He suspects the park's wild
bovines may have a natural immunity to brucellosis. "It hasn't hurt
their population here."
Coleman says that
blood-serum tests for brucellosis, which show 53 percent of
Yellowstone's herd to be infected, are not as accurate in buffalo
as in cattle. Follow-up tissue culture tests reveal that few bison
are actually contagious.
dismisses this claim as "balderdash," arguing that cattle tested
under the same conditions would give similar
Also of concern is the impact on private
property from beasts that can smash a fence flat with their 2,000
pounds. Bernie Kuntz, regional information officer for Montana's
Fish, Wildlife and Parks Department in Bozeman, says his agency has
had continual complaints from landowners. "Bison chase their
horses, go through fences, and rub the siding off their houses."
John Emmerich, Wyoming Game and Fish Department
wildlife management coordinator in Cody, says most people in his
area were happy to see the bison, but he fears that the animals
could compete with species like bighorn sheep for
Emmerich is working on a state management
plan for the bison that wander across Yellowstone's eastern
boundary into Wyoming; one option, he says, might be hunting the
Meanwhile, the National Park Service,
the U.S. Forest Service, and Montana are putting together a
long-range management plan for bison that drift into that
According to John Varley, director of
Yellowstone's Center for Resources, options include: continuing the
status quo, letting the bison range freely, closing snowmobile
trails, and "some mix and match."
Americans, who find the practice of gunning down the errant bison
repugnant, have proposed taking disease-free animals from
Yellowstone's surplus to start their own herds. Some of the
inter-agency alternatives, Varley says, include such a program. The
Park Service has already rejected one U.S. Department of
Agriculture proposal: to wipe out the infected Yellowstone herd and
replace it with brucellosis-free animals. "You'd have to nuke the
ecosystem," Varley says.
The real issue, most
observers agree, is too many bison. Ever since 1969, park bison
numbers have been doubling about every 10 years. "Where are you
going to put 50,000 buffalo?" asks Wyoming's
Coleman says the park is not opposed to
controlling bison within its borders. "But," he says, "it's got to
be done with some class, and some reverence for the animal."
The writer lives and
works in Wapiti, Wyoming.
more information about the forthcoming management plans, write:
Superintendent, Yellowstone National Park, P.O. Box 168,
Yellowstone National Park, WY 82190; John Emmerich, Wildlife
Management Coordinator, Wyoming Game and Fish Department, 2820
State Highway 120, Cody, WY