From late fall to spring, males and females are separate. In the 1800s buffalo could be found all across North America. Most of the bison were killed in the 1800s. A few were protected. Today, many bison are found in parks in the northwest US and Canada.
Healthy adults have little to fear, especially in their herds.
Bison's only significant predators are wolves and grizzlies that usually have to content themselves with preying on stray calves or old, weakened adults. The bison's primary defense is to stampede, running away from predators at speeds up to 32 miles per hour, faster than a wolf. They also can use their hooves and horns as formidable weapons against intruders. Here are a few other websites where you can get more information about bison. Here you find more information on bison life cycle, diet, habitat, and history from the Oakland Zoo.