• Males clash heads during the rut.

The American bison, also known as the American buffalo, reproduces through live birth on land, with the young not hatching from eggs or larvae. The gestation period lasts 9 months and 1 week, after which the female gives birth to a single calf. Newborn calves quickly stand and remain close to their mother. Females produce offspring at an interval of 1 to 2 years; a female typically gives birth to one calf after approximately nine months of pregnancy. The species develops on land, outside of bodies of water, in nests built on or near the ground, which are located directly on the surface of the soil. Only the mother exhibits parental care within these ground nests. Maturity is reached from 2 to 5 years of age, and reproduction always occurs through sexual reproduction, involving fertilization without generational changes.