Travel Reference
In-Depth Information
BISON & BRUCELLOSIS
A national symbol long revered by Native Americans, Yellowstone's bison are some of the USA's last free-roam-
ing herds. Despite protection within national parks, their existence outside the park is precarious. About half of
Yellowstone's 3900 bison test positive for brucellosis, a bacterium that causes domestic cows to abort their calves.
Brucellosis spreads from the region's abundant elk population to the bison, who merely carry the bacteria while
themselves remaining unaffected.
For many years, bison that strayed outside the park have faced removal, a term which usually meant extermina-
tion. In 2000, a long-term management plan was put into place under which 840 bison were shipped or
slaughtered. After many lawsuits, public dissatisfaction and controversy, the plan has seen considerable revision.
In recent years, bison removal has declined, in part due to some success with a cattle brucellosis vaccine. Manage-
ment is now looking to remote vaccination as a potential solution. In addition, 80,000 acres in Montana have been
opened up as a sanctuary.
North America's largest cat, the mountain lion (aka cougar) prefers remote, forested
areas of the park. With a size and shape similar to that of a smallish (African) lioness, the
mountain lion may reach 7.5ft from nose to tail and can weigh up to 170lb. Even biolo-
gists who study it rarely encounter this solitary and highly elusive creature. It typically
preys on mule deer, elk and small mammals, following their summer migrations to higher
ground. While curious mountain lions are known to 'stalk' people without harmful intent,
they occasionally attack humans.
Birds
Boasting 316 recorded winged species (of which 148 stay to nest), Greater Yellowstone
offers a delightful bird-watching experience. The American Bird Conservancy recognizes
Yellowstone National Park as a 'globally important bird area.' Noteworthy large birds in-
clude common ravens, resurgent peregrine falcons, reclusive sandhill cranes, honking Ca-
nadian geese and American white pelicans. Smaller birds like pesky black-billed magpies
and yellow-headed blackbirds are common sights.
Birds of Prey
This group of birds (aka raptors) includes eagles, falcons, hawks and harriers. Sweeping
across lakes, forests or plains in search of fish or small game, they are some of the most
interesting and easily watched birds in the area.
