Watch hormonal bison take out its aggression on cars at Yellowstone

Bison on road at Yellowstone National Park
(Image credit: Getty)

Male bison become particularly aggressive in late summer as their rutting season reaches its peak, and as some visitors to Yellowstone National Park found out, they sometimes take out their frustration on traffic jams.

Earlier this month, another group of Yellowstone visitors narrowly avoided disaster when they left their vehicle to get a closer look at a pair of sparring bison. That time the animals were preoccupied with their own fight for dominance, but this latest clip shows a male turning his attention to a line of cars that has stopped to allow a herd to pass.

The incident (which you can watch below) was captured by visitor William Ogonowski last week. As Fox 5 NY reports, the animals were passing peacefully among the vehicles when a pair became aggressive and began to bellow.

According to the National Park Service, it's believed that these bellows serve to announce the male animals' presence and establish dominance through frequency, duration, and volume. 

"These vocalizations may reveal information about the male's competitive ability, physiological quality and condition, and sexual receptivity," says the NPS, "in other words, the bellows denote fitness-related information."

One of the pair eventually rams a car with its horns before running off the road. The passengers and driver were unharmed.

Staying safe

Bison cause more injuries than any other animal at Yellowstone, including bears, but visitors often underestimate them. The park recently revealed a poster urging hikers not to pet the fluffy cows after a series of incidents where people were gored or tossed in the air after getting too close.

Safety guidelines from the NPS recommend staying at least 25 yards (or 23 meters) away from bison. Although usually peaceful, the animals can run three times faster than a human, and males may weigh over 2,000lb.

Cat Ellis

Cat is the editor of Advnture, She’s been a journalist for 15 years, and was fitness and wellbeing editor on TechRadar before joining the Advnture team in 2022. She’s a UK Athletics qualified run leader, and in her spare time enjoys nothing more than lacing up her shoes and hitting the roads and trails (the muddier, the better), usually wearing at least two sports watches.