Video captures an agitated bull bison launching a man several feet into the air at Bridge Bay Campground during a completely unprovoked attack.

A grandfather is recovering after a Yellowstone bison attack left him seriously injured during the animals’ mating season.

The visibly agitated bull bison was roaming the campground and charging at other groups of campers, as seen in a video taken by Mike MacLeod, a professional photographer based in Bozeman, Mont., about...