When discussing the large, shaggy mammals that roam Yellowstone National Park, a common point of confusion often arises concerning their proper identification. Many people use the terms “buffalo” and “bison” interchangeably, yet these words refer to distinct animal groups. This distinction reflects significant biological and geographical differences between these impressive bovids. Understanding these differences clarifies which iconic animals truly reside in Yellowstone’s expansive wilderness.
Buffalo vs. Bison: Unpacking the Terminology
The term “buffalo” technically refers to species found in Africa and Asia, not the animals native to the American plains. True buffalo include the African Cape buffalo and the Asian water buffalo. Several physical characteristics distinguish bison from true buffalo. Bison possess a prominent shoulder hump, large heads, and a shaggy coat. In contrast, buffalo typically have smoother coats and longer, often curved horns, while bison horns are shorter and sharper.
Yellowstone’s Resident Herds
Yellowstone National Park is home to American Bison. These bison represent the largest free-ranging population on public lands in the United States, and Yellowstone is unique as the only place where they have continuously lived since prehistoric times. The park’s population fluctuates, with recent estimates around 5,400 individuals. Yellowstone bison are recognized for their genetic purity, having largely avoided interbreeding with cattle. Recent research indicates the park’s bison now function as a single, interbreeding population.
The American Bison’s Comeback Story
The American Bison faced near extinction in the 19th century due to widespread hunting and eradication efforts. Their population, once numbering in the tens of millions, dwindled to just a few hundred by the late 1880s. Yellowstone National Park contributed significantly to the species’ survival, as a small remnant herd found refuge within the park’s boundaries. In 1902, conservation efforts were bolstered by the introduction of privately owned bison, which bred with the surviving wild population. This intervention, alongside ongoing protection, led to a remarkable recovery.
Bison are considered a keystone species within the Yellowstone ecosystem, meaning their presence significantly influences the environment. Their grazing habits help maintain the health and diversity of grasslands, preventing any single plant species from dominating. Their wallows—shallow depressions created by rolling in the dirt—form microhabitats that benefit various plant and animal species. The ongoing Bison Conservation and Transfer Program supports the species’ restoration by relocating Yellowstone-origin bison to tribal lands and other suitable habitats, contributing to genetic diversity and ecological restoration.