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A bison grazing in the Tetons mountains in Wyoming
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  • States:
    Wyoming
    Montana
    Idaho

An enduring symbol of freedom and the West, bison once roamed the U.S. grasslands.

While the landscape of the USA has changed in modern times, the love for this majestic mammal has remained a constant. The National Bison Legacy Act was signed into law by U.S. President Barack Obama in May 2016, making bison the USA's national mammal. Thanks to the work of conservationists, the National Park Service and private land owners, bison herds are growing nationwide, increasing from just 1,000 in 1890 to more than 500,000 today.

What Are Bison?

Unique to North America, bison are the continent's largest mammal, and can grow to 2 meters tall and weigh up to 907 kilograms. They're grass-eating herbivores and are covered in shaggy black-brown fur, which protects them from the cold, snowy winters. Bison mate in summer before giving birth to a single red-colored calf in spring.

Bison are the continent's largest mammal, and can grow to 2 meters tall and weigh up to 907 kilograms.

bison are the continent's largest mammal, and can grow to 2 meters tall and weigh up to 907 kilograms.
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Bison or Buffalo?

Bison is the scientific term for this mammal, but many people also call them buffalo. Which is correct? Technically, the word "buffalo" just refers to African and Asian buffalo, whereas the North American bison is related only to the European bison. But the name buffalo has been used for so long that you'll see it as a common alternative.

Bison is the scientific term for this mammal, but they're also called buffalo.