Bison (Buffalo)


From Yellowstone Wildlife: A Watchers Guide 
by Todd Wilkinson.

Our Window To The Past

By the middle 1800s, the population of the American bison had already started to decline, from a one-time high of perhaps 60 million animals. Over the next fifty years, widespread throngs of millions were reduced to regional thousands, and the thousands then plummeted to fewer than 50 wild bovines in the entire lower 48 states.

Teetering on the brink of extinction, the last few free-roaming bison in the United States took refuge in a corner of northwest Wyoming known as Yellowstone National Park. The animals you see today along the roadsides in Yellowstone are descendants of those survivors-behemoths from a time when bison, or "buffalo" as they are popularly known, were the largest terrestrial mammals in North America.

[image2]The number counted in Yellowstone today is about 2,500, divided into three distinct herds that stretch across the park. The sight of these herbivores grazing across the rolling plateaus brings thoughts of pre-history to mind, when ancestors of these 2,000-pound creatures first crossed the Bering Strait from Euruasia and quickly populated the Great Plains of this continent.

Until the 1950's, the National Park Service operated the "Buffalo Ranch" near Rose Creek in Lamar Valley (now home to the Yellowstone Institute) where bison were carefully husbanded and cropped to ensure growth of the population. The Yellowstone bison (Bison bison) has lineage from a subspecies that wandered from the northern woods and plains. Males (called bulls) and females (called cows) have black horns, which are not shed like the antlers of elk, deer, and moose. The bulk of a bison's coat is composed of shaggy, reddish -brown fur, though the head is dark brown. Some animals have dark brown manes and beards. Bulls are larger, standing six feet tall at the shoulder while females grow to five feet.

[image3]Docile and seemingly oblivious to activity around them, bison have a calm demeanor, sometimes misinterpreted as an open invitation to approach. They are not, however, domesticated cows in a pasture, but wild creatures that are dangerous to those who invade their privacy. It may surprise some that three times as many humans have been gored by bison since 1980 than the total number of humans attacked by grizzly and black bears combined. Distance should be afforded, especially to lone bulls who have sought seclusion for a reason, or to cows with young calves. 

The bison herds are most active in the cool of morning and evening, while the heat of day is usually a time when adults rest and ruminate (chew their cud). Caution: as the flyers distributed at park entrance stations suggest, the 2,000 -pound bison use Yellowstone roads in the summer and winter, night and day. Drive with care!

Where to find bison

An excursion to Yellowstone is not complete without a drive through Hayden Valley. Here, you may see hundreds of bison flanking the roadway during daylight hours. Young bulls may be sparring, or adults may seek relief from the summer heat in streams that dissect the valley floor. Nearby, you can see bison on the northern shore of Yellowstone Lake, particularly in Pelican Valley east of Fishing Bridge. 

Clusters of bison are viewed regularly in the Lower Geyser Basin and the Firehole River drainage, occupied by the Mary Mountain Herd; and in the Lamar Valley along the Lamar River, home of the resident Norther Herd. Both herds have sources of controversy, because bison from these groups migrate outside of the national park during periods of heavy snow. The state of Montana enlisted hunters and game wardens to shoot and kill wandering bison, because they may carry the disease brucellosis, which can cause abortions in domestic cattle. Park scientists are now developing management strategies that would allow the Yellowstone bison, the largest fee roaming population in the world, to continue to use lands outside the park as a winter range. Continue to the next page, Black Bear.

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