Biology Reference
In-Depth Information
Historically, wolves and Native Americans were the main predators of bison, and it may well be that
the burgeoning population of wolves in Yellowstone Park will eventually assume that role. Currently
the wolves seem to be concentrating their efforts mostly on elk, which are easier to kill than bison. As
the park's overpopulation of elk is brought under control by the wolves, however, it seems likely that
they'll begin to turn their attention to the bison.
In addition to these unfenced wild herds, there are also what I think can reasonably be termed semi-
wild herds, which are fenced, but in such enormously large areas, encompassing tens of thousands of
acres, that they can roam freely for all practical purposes. These include the bison in Custer State Park
and Wind Cave National Park, among others.
Bison are not only incredibly hardy; they're also unrivaled for size in North America. Cows normally
weigh about one thousand pounds, and bulls 1,300 to 1,500 pounds, but a really large bison bull can
stand over six feet high at the shoulder and weigh over two thousand pounds! This is heavier than the
largest moose, brown bear, or polar bear.
Bison are huge, but they're also fast and have immense endurance. They can run over thirty miles an
hour at top speed, and at a slower pace they can run for hours without stopping. All in all, this makes
the bison an exceptionally difficult target for even a very large predator.
The power and durability of the bison was highlighted by a bizarre contest that took place in 1907
between Pierre, a bison bull, and a series of Mexican fighting bulls. This incident began when several
Mexican officials visited Fort Pierre, South Dakota, to view some bison confined on a ranch there. The
officials weren't impressed by the slow movements and docile behavior of the bison, and made dispar-
aging remarks about them. A Mexican fighting bull, they told their hosts, would make short work of a
bison.
This prompted a retort, one thing led to another, and soon a fight was arranged in the bull ring in
Juarez, Mexico. There, to settle what had escalated into a rather rancorous dispute involving the nation-
al pride of both countries, Pierre was to take on a succession of fighting bulls (assuming he outlasted
the first one) in a quadruped version of a Demolition Derby.
When Pierre was brought into the ring, he placidly lay down in the warm sunshine, unfazed by the
jeers of the hostile crowd. Then the Mexican fighting bull was brought in, accompanied by loud cheers.
After looking his adversary over, the Mexican bull finally approached Pierre, who got to his feet at
that point, but made no other move. Four times the fighting bull attacked, and each time Pierre simply
turned to meet his charge head-on.
A bison, with the bulk of its weight centered over its front quarters, pivots on its front legs, whereas a
domestic bull pivots on its hind legs. The fighting bull was evidently baffled by its opponent's ability to
pivot so quickly, and the results of its charges were stunning in more ways than one. The first time they
collided, the Mexican bull staggered backward. The next time it dropped to its knees after the crash,
and the third and fourth times it went all the way down. This was enough for the fighting bull, which
