Plains bison in the context of Canadian Prairies

The American bison (Bison bison; pl.: bison), commonly known as the American buffalo, or simply buffalo (not to be confused with true buffalo), is a species of bison that is endemic (or native) to North America. It is one of two extant species of bison, along with the European bison. Its historical range circa 9000 BC is referred to as the great bison belt, a tract of rich grassland spanning from Alaska south to the Gulf of Mexico, and east to the Atlantic Seaboard (nearly to the Atlantic tidewater in some areas), as far north as New York, south to Georgia, and according to some sources, further south to northern Florida, with sightings in North Carolina near Buffalo Ford on the Catawba River as late as 1750.

Two subspecies or ecotypes have been described: the plains bison (B. b. bison), smaller and with a more rounded hump; and the wood bison (B. b. athabascae), the larger of the two and having a taller, square hump. Furthermore, the plains bison has been suggested to consist of a northern plains (B. b. montanae) and a southern plains (B. b. bison) subspecies, bringing the total to three. However, this is generally not supported. The wood bison is one of the largest wild species of extant bovid in the world, surpassed only by the Asian gaur. Among extant land animals in North America, the bison is the heaviest and the longest, and the second tallest after the moose.

A bison (pl.: bison) is a large bovine in the genus Bison (from Greek, meaning 'wild ox') within the tribe Bovini. Two extant and numerous extinct species are recognised.

Of the two surviving species, the American bison, B. bison, found only in North America, is the more numerous. Although colloquially referred to as a buffalo in the United States and Canada, it is only distantly related to the true buffalo. The North American species is composed of two subspecies, the Plains bison, B. b. bison, and the generally more northern wood bison, B. b. athabascae. A third subspecies, the eastern bison (B. b. pennsylvanicus) is no longer considered a valid taxon, being a junior synonym of B. b. bison. Historical references to "woods bison" or "wood bison" from the Eastern United States refer to this synonym animal (and to their eastern woodland habitat), not to B. b. athabascae, which was not found in the region. Its European kind B. bonasus or wisent —also 'zubr' or colloquially 'European buffalo'— is found in Europe and the Caucasus, reintroduced after being extinct in the wild.

The wood bison (Bison bison athabascae) or mountain bison (often called the wood buffalo or mountain buffalo), and Athabaskan bison (or Athabaskan buffalo), is a distinct northern subspecies or ecotype of the American bison. Its original range included much of the boreal forest regions of Alaska, Yukon, western Northwest Territories, northeastern British Columbia, northern Alberta, and northwestern Saskatchewan. An attempt is ongoing to reintroduce them into the wilderness of Eurasia by Sakha Republic of Russia.

Pure-bred wood bison were believed to be extinct after the late 1920s as a result of intermixing with plains bison in Wood Buffalo National Park, then believed to be their last refuge. A nearly pure herd was found in 1957 in an isolated portion of the park. Herds called the Firebag River and Ronald Lake herds potentially have had no contact with the Wood Buffalo National Park herd.

The conservation of bison in North America is an ongoing, diverse effort to bring American bison (Bison bison) back from the brink of extinction. Plains bison, a subspecies (Bison bison bison), are a keystone species in the North American Great Plains. Bison are a species of conservation concern in part because they suffered a severe population bottleneck at the end of the 19th century. The near extinction of the species during the 19th century unraveled fundamental ties between bison, grassland ecosystems, and indigenous peoples’ cultures and livelihoods. English speakers used the word buffalo for this animal when they arrived. Bison was used as the scientific term to distinguish them from the true buffalo. Buffalo is commonly used as it continues to hold cultural significance, particularly for Indigenous people.

Recovery began in the late 19th century with a handful of individuals independently saving the last surviving bison and the government efforts to protect the remnant herd in Yellowstone National Park. Dedicated restoration efforts in the 20th century bolstered bison numbers though they still exist in mostly small and isolated populations. Expansion of the understanding of bison ecology and management is ongoing. The contemporary widespread, collaborative effort includes attention to heritage genetics and minimal cattle introgression.

Prairie dogs (genus Cynomys) are herbivorous burrowing ground squirrels native to the grasslands of North America. There are five recognized species of prairie dog: black-tailed, white-tailed, Gunnison's, Utah, and Mexican prairie dogs. In Mexico, prairie dogs are found primarily in the northern states, which lie at the southern end of the Great Plains: northeastern Sonora, north and northeastern Chihuahua, northern Coahuila, northern Nuevo León, and northern Tamaulipas. In the United States, they range primarily to the west of the Mississippi River, though they have also been introduced in a few eastern locales. They are also found in the Canadian Prairies. Despite the name, they are not actually canines; prairie dogs, along with the marmots, chipmunks, and several other basal genera belong to the ground squirrels (tribe Marmotini), part of the larger squirrel family (Sciuridae).

Prairie dogs are considered a keystone species, with their mounds often being used by other species. Their mound-building encourages grass development and renewal of topsoil, with rich mineral and nutrient renewal in the soil, which can be crucial for soil quality and agriculture. They are extremely important in the food chain, being important to diets of many animals such as the black-footed ferret, swift fox, golden eagle, red tailed hawk, American badger, and coyote. Other species, such as the golden-mantled ground squirrel, mountain plover, and the burrowing owl, also rely on prairie dog burrows for nesting areas. Grazing species, such as plains bison, pronghorn, and mule deer, have shown a proclivity for grazing on the same land used by prairie dogs, with their regeneration of topsoil being important for maintaining healthy humus. Prairie dogs have some of the most complex systems of communication and social structures in the animal kingdom.

A buffalo jump, or sometimes bison jump, is a cliff formation that Indigenous peoples of North America, beginning with Clovis culture, historically used to hunt and kill plains bison in mass quantities. The broader term game jump refers to a man-made jump or cliff used for hunting other game, such as reindeer.

The Yellowstone bison herd roams the Greater Yellowstone Ecosystem. The bison herd is probably the oldest and largest public bison herd in the United States, estimated in 2020 to comprise 4,800 bison. The bison are American bison of the Plains bison subspecies. Yellowstone National Park may be the only location in the United States where free-ranging bison were never extirpated, since they continued to exist in the wild and were not reintroduced.