American bison are not only the largest animal in North America, but they are also the National Animal of the United States. There are two subspecies, the plains and wood bison. Wood bison are larger, and weigh up to 2,250 pounds, versus the 2,000 pound plains bison. Bison form herds of up to 10,000 members.
An American Bison’s main predators are grey wolves and brown bears. They protect themselves with their horns and kicking. A healthy adult bison can hold it’s own against a pack of wolves, but predators go after calves and the old and crippled individuals. Since bison travel in herds, they all will turn to face the threat, or all run together. Bison can run 35 mph. Bison can also hurdle 6 feet over obstacles.
American bison live on the Great Plains and in Canadian forests. The graze on low-lying plants and grasses. A bison herd needs a lot of food every day, up to 25 pounds! For all of the herd to eat enough, bison need to be on the move constantly.
American bison breed in late summer. The males, or bulls, have very aggressive mating battles. They lock horns and try to injure the opponent until he submits. Breeding battles rarely result in death, but the looser often is badly bruised. The male then mates with the female in heat. To detect other females in heat in the area, male bison use their acute sense of smell to the particular females. Cows then carry the calf for about 9 months. The calves are born is spring, when the weather is the best for raising young. The calves remain with their mother for a little over a year.