Older bulls are in smaller groups of 12 or fewer animals near the periphery of the mixed group. A straight dominance hierarchy exists. He is dominant over all others. Animal three is usually a female and is dominant over weaker females and all males her own size. A particular animal's position in the hierarchy is constantly being challenged.
Grooming is an important daily activity.
The animal scrubs head, neck, and the sides of its body on trees, branches and tree trunks. It also rolls or wallows in loose sand and dust. The wallowing is sometimes used as a displacement activity instead of fighting. The bison is most active during the morning and evening. It is extremely playful up to 2 years of age.