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The American bison (Bison bison bison), commonly (and erroneously) called the buffalo, came to the North American continent from Asia, crossing over the land bridge during the ice age. Through the centuries the bison slowly moved southward. When Europeans discovered America, the bison ranged over a great portion of the continent. They had reached as far south as Mexico and as far east as the present states of New York, Maryland, Georgia, and even Florida. They apparently followed the river valleys and mountain passes to the Pacific Northwest. The greatest numbers were, however, found in the plains and prairies from the Rockies to the Mississippi River and down into Texas. At their peak, bison probably numbered as many as 60-70 million.

Bison are ruminants (animals which chew their cud) belonging to the cattle family. Like their close relatives, cows and sheep, they are cloven hoofed. The bulls, which are larger than the cows, stand 5 to 6 feet high at the shoulders and may weigh nearly a ton. Cows are much smaller, lacking the huge “hump” of the males, and usually weigh around 600-800 pounds. (The familiar shoulder hump of the bison is really the bones and strong muscles required to lift the heavy head.) Bison have horns (permanently attached) rather than antlers (which are shed annually). Both sexes have horns. Bulls’ horns stick straight up, while cows’ horns curve inward at the tips.

Despite their great size and weight, bison can charge and run very quickly. They have amazing mobility and can easily outrun a man. Their bones have been found with those of mountain sheep on summits where horses could not find a footing and man could reach only by climbing. They are also accomplished jumpers and were known to easily jump our four foot fence before the hot-wire was in place. Bison are good swimmers and will often cross a lake or river merely to graze on the other side.

In the spring the bison shed their heavy winter coats, the hair hanging about them in tatters. To relieve themselves of the hair and perhaps to relieve their itching skin, they rub against large stones and trees. During the summer months, to relieve themselves from biting insects, bison wallow in dust or sand. Early travelers on the plains wrote of the “buffalo wallows” they found, often a foot or more deep and 15 feet across. In captivity bison may rub on fence posts, destroying fences.

The Native Americans would often take the animals while they had little hair on their backs and hindquarters. Indian clothing was made from the tanned, more workable skins of the cows; their lodges and shields from the thick, tanned hide of the bulls. The thicker hide of the bulls has been known to withstand shots from handguns, the bullets bouncing harmlessly off.

Bison are social animals and are seldom seen alone. Only the occasional old bull, no longer able to compete with younger bulls, may wander off to spend his days in solitude or with other bulls like himself.

We now know that the great north-south migrations once ascribed to the bison never occurred. The treks probably were not more than 300-400 miles long. The herds moved in various directions in their search for food and water, as well as to escape hot weather on the southern plains. The great herds were actually made up of groups of smaller herds. Only when panicked did these smaller groups appear to lose their identity. It is questionable whether the original small herds ever reformed after a stampede.

Since early days when the first ranchers noted the extreme hardiness of the buffalo, men have wanted to breed this hardiness into their cattle. The hybrid resulting from crossing cattle and buffalo is known sometimes as a cattalo or beefalo. With few exceptions such attempts have failed, as the hybrids are usually not able to reproduce. Today, some ranchers are attempting to commercially raise purebred bison for food. Not only are these animals kinder to the environment due to their eating habits, especially on marginal rangeland with seasonal rainfall, but bison are much more efficient in converting feed to muscle mass and so eat less than cattle. The meat itself is much leaner than beef, an important point in a more health-conscious society.

When snow covers the ranger the bison root through the snow with their muzzles and heads. Students of the bison question whether they ever use their feet to uncover the grasses.

Their breeding season is from mid to late summer. The herd at this time becomes restless and may be dangerous. The bulls, aloof most of the year, now drift among the cows and calves. The bulls bellow hoarsely and become quarrelsome. Many fights occur; the combatants, with lowered heads, paw the earth, rush and butt one another. The battles are usually short-lived, the defeated bull retreating to a safe distance.

Calves are born in the following spring, usually between the middle of April and the end of May, but some arrive as late as October. They are a bright buff color, almost orange, but will turn dark brown by the end of their first year. Calves can walk within an hour, and keep up with the running herd by the end of their first day. The cow and new calf soon rejoin the herd, and the youngsters begin grazing very young, although some may still nurse when nearly a year old. Bison mature at 7 to 8 years old, and may live to be 25 to 30.

With their great size, speed, and weight, bison make formidable prey. A single healthy bison is more than capable of driving off a single wolf, and a full herd of bison is more than a match for a pack of hungry wolves. Predators must try to single out a lone, sick or injured bison which might be weak enough to fall victim.

We will never know just how many bison once lived on this continent. The giant herds were nearly gone before any systematic attempts were made to determine their numbers. Ernest Thompson Seton estimated that there may have been 60 million of these animals around the year 1800. A reasonable estimate places their numbers at 40 million in 1830, when systematic destruction of the bison began. By 1870-71 not more than 5 1/2 million remained, and by 1879, only stragglers were seen drifting northward along their old trail.

Historians say the U.S. Army was encouraged to slaughter bison to control the West. As the stream of white settlers moving westward increased, the Indian hunters found it increasingly difficult to find enough bison to supply their tribes with meat. All of this led to raids on white settlements and massacres of the settlers. Destroying the bison was used to subdue the Indians. This of course left other predators, such as the wolf, without food as well.

Much of the initial destruction of the herds was done by hunters. Hunters often killed 250 bison a day and many said they killed from 2,500 to 3,000 a year. Hunting was done primarily for hides and for meat. However, the only meat generally taken was the tongues. By 1870 trading in buffalo was the chief industry of the plains. A single firm in St. Louis bought 250,000 hides in 1871. In 1873-74, auctions in Forth Worth, Texas, were moving 200,000 hides in a day or two. Yet, for every hide taken, 4-5 bison were killed.

Construction of the railroads across the plains hastened the destruction of the bison. Thousands were shot to supply construction camps with meat. Hunting from train windows was advertised widely and passengers engaged in the “sport” of shooting from the open windows as the bison raced beside the train. By 1874, the southern herd was gone.

With the southern herd gone, the bison hunters turned to the northern herd. Between 1876 and 1883 they destroyed it. Those who knew the buffalo country said at least 5,000 hunters and skinners were on the northern range in 1882. The hunting season of 1883 completed the annihilation of the northern herd. The hunters apparently did not realize the bison were gone, for many insisted that the herd had gone into Canada and would return.
The year of 1900 marked the all-time low in bison numbers: less than 300 wild animals remained on the North American continent out of the millions that had once lived here.

Fortunately, during the time the wild bison herds were being destroyed, a number of people were developing small captive herds. Some better-known captive herds were the famous Goodnight herd of Texas, the Pableo-Allard herd of Montana, and the Blue Mountain Forest Association herd of New Hampshire. It is largely from these three herds that the bison in national refuges and parks have come.

Bison are found today in numerous private and state herds. One of the largest herds in the United States, numbering about 1,300 animals, is in the Custer State Park in South Dakota. Surveys of the bison herds in the United States and Canada in recent years show a continental population of 20,000 to 22,000 animals. While this is a small number when compared with the great herds that once ranged the continent, it is large enough to assure the well-being of the American bison in the foreseeable future.