BISON VIDEO: Officials at Yellowstone are saying it is bison mating season and the male bison are very aggressive right now. Remember to keep a distance of 25 yards from all bison and elk and 100 yards from other wildlife. Thanks to Yellowstone National Park for this video. Send us your photos and videos: nbcmontana.com/chimein | NBC Montana

HEADSTRONG: A herd of bison blocked a road in Yellowstone National Park during their annual rutting season, with one getting aggressive toward a stopped vehicle and ramming into the side of it. https://abcn.ws/3T5bJwS | ABC News

Bison herd migration.🦬🦬🦬 | Jake Slater

WATCH THESE BISON SWIM THE YELLOWSTONE RIVER 👀 This small herd of bison decided to take a nice cold swim this spring (notice the melting snow ❄️ on the riverbank) in the Yellowstone River! Bison are the largest mammal in North America. Male bison (called bulls) weigh up to 2,000 pounds and stand 6 feet tall, while females (called cows) weigh up to 1,000 pounds and reach a height of 4-5 feet. It's hard to believe these large creatures can swim but as you can see from the video they do just fine!