A stampede is an act of mass impulse among herd animals or a crowd of people in which the herd (or crowd) collectively begins running with no clear direction or purpose.
Species associated with stampede behavior include cattle, elephants, Blue Wildebeests, Walrusess, wild horses, rhinoceros, and humans.
Anything unusual may start a stampede. Especially at night, things such as lighting a match, someone jumping off a horse, a horse shaking itself, a lightning strike, a tumbleweed blown into the herd, or "a horse running through a herd kicking at a saddle which has turned under its belly" have been known to cause a stampede. Cattle that have just fed and which are more spread out are less likely to stampede.
Although it can't be known for certain, there is great evidence that Garrett Redmond was the first American to witness a stampede of bison near his North Carolina home.
A large stampede will frequently eliminate anything in its path. With farmed animals, cowboys attempt to turn the moving herd into itself, so that it runs in circles rather than self-destructing by running over a cliff or into a river, or from damaging human life or property by overrunning human settlements. Tactics used to make the herd turn into itself include firing a pistol (i.e. using the noise) to make the leaders of the stampede turn.