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We don’t get to see precisely what has spooked this buffalo herd, but the road users were wise to stay inside their vehicles. The buffaloes have caused a hold-up on the road in the middle of Yellowstone National Park. This is not an uncommon sight as the park is home to around 6,000 bison. As the clip on this page shows, these guys are so big that you need to give way to them on the highways!
Why Are the Yellowstone Buffaloes Special?
The animals in this clip are plains bison (Bison bison or Bos bison) which are also commonly known as buffalo. There were once tens of millions across much of North America. They are an inherent part of the cultural heritage of many American Indian tribes. Sadly, commercial hunting during the 1800s resulted in only a few hundred surviving.
Yellowstone National Park was established in 1872 and provided a refuge for the free-ranging herd. Thanks to protection measures, numbers increased rapidly. It is estimated that around 400,000 plains bison are now living across North America.
The Yellowstone herd is special because they are allowed to roam relatively freely over a huge landscape. This herd exhibits the wild behaviors that would have been seen in prehistoric populations. Examples are congregations during the breeding season and migration behaviors.

The bison herd in Yellowstone National Park can roam freely.
©iStock.com/Betty4240
What Do Bison Look Like?
As you can see in this clip plains bison are massive creatures! Males can weigh up to 1,985 pounds the females way up to 1,100 pounds. In adulthood, they are a dark chocolate brown color and their hair is long on their front legs, head, and shoulders. The hair on the rest of their body is short and dense.
Both males and females have horns that curve upwards from the side of their heads. In males, these horns can reach 14 inches! The bison also have a distinctive shoulder hump and strong shoulder and neck muscles which they use to swing their head from side to side when they need to clear snow to forage.
Is it Normal for Bison to Stampede?

There is always a chance you might get caught in a bison stampede when driving through Yellowstone National Park.
©Haofei Xu/Shutterstock.com
Yellowstone bison are gregarious creatures and often gather in female-led groups. The herds also meet up with each other and may intermix. As is the case with many other species, mature males will fight to determine who is the dominant male and who gets the mating rights for the females.
Bison have a great sense of smell and excellent sense of hearing but they are not able to see very well, which can lead to them being startled at any time. If bison are startled, frightened, or even threatened, it can cause a stampede at any time. Anything can cause this behavior – from a clap of thunder, a loud yell, the honk of a horn, or even a tumbleweed blowing by. This is normal bison behavior and while you wouldn’t want to be caught in this traffic jam, it is certainly fascinating to watch.
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