in july and august, right when the haden party was making their way down these hills, dust fills the air in the valley. g thruntine bison run is under wa. female bison tend to mate with the most dominant bulls. [f thisoreb modeling behavior by the males is a display of power and aggression during mating season, these bull will lose to 400 pounds. it is an interesting ritual. but highly effective.f becausthese e in yellowstone the bison are 3 thriving and