The American Bison, often referred to as the buffalo, once faced near-total extinction across North America, but Oklahoma played a significant role in the species’ survival. Today, the state is home to some of the largest and most genetically significant conservation herds in the United States. These populations roam across diverse landscapes, from protected mountain refuges to vast expanses of tallgrass prairie. Oklahoma’s herds represent a successful ecological recovery and a continued commitment to maintaining this iconic animal.
Current Bison Herds and Locations
Oklahoma hosts several prominent bison herds, providing unique opportunities for public viewing. The Wichita Mountains National Wildlife Refuge in the southwest maintains a herd, typically numbering around 650 individuals, that roam freely across the refuge’s 59,000 acres of mixed-grass prairie and rocky terrain. This herd is a direct descendant of the 15 animals first brought to the site in 1907, making it a foundation herd for modern conservation efforts.
Another major population is located at the Joseph H. Williams Tallgrass Prairie Preserve in Osage County, managed by The Nature Conservancy. This herd is one of the largest conservation herds in the country, often exceeding 2,500 animals, occupying nearly 40,000 acres of protected tallgrass ecosystem. Visitors can observe these animals from a 15-mile driving loop. Beyond these public lands, the Osage Nation maintains a growing herd on its 43,000-acre ranch, which is a modern example of tribal-led conservation. Recent transfers of six bison from the Bronx Zoo were made to this herd to enhance its genetic health.
The History of Bison in Oklahoma
Before European settlement, the American Bison population was vast, with estimates suggesting tens of millions of animals once ranged across the continent, including the grasslands of what is now Oklahoma. These animals were a keystone species; their grazing and trampling shaped the prairie ecosystem, and they were integral to the culture and survival of many Indigenous peoples. This population was decimated in the 19th century by organized hunting campaigns, which left fewer than 1,000 bison alive by the late 1880s.
Oklahoma became a sanctuary for the species during this period of near-extinction. A coordinated effort led by the American Bison Society and the New York Zoological Society resulted in the first animal reintroduction in North America in 1907. Bison were shipped via rail to the newly established Wichita Forest Reserve. This action was instrumental in saving the Southern Plains herd from complete disappearance and ensuring the species’ long-term survival.
Conservation Efforts and Herd Management
Modern bison management in Oklahoma focuses on maintaining the genetic health and ecological function of the herds. The near-extinction event created a severe genetic bottleneck, meaning all contemporary bison descend from a very small number of founders. Consequently, a primary conservation strategy involves translocating bison between herds to increase gene flow and prevent inbreeding depression. This depression can reduce the population’s ability to adapt to environmental changes, making genetic diversity a priority.
Ecologically, management techniques are employed to mimic the natural processes that historically shaped the prairie. The Tallgrass Prairie Preserve utilizes a “patch-burn-grazing” model, where controlled burns create a mosaic of burned and unburned areas. Bison concentrate their grazing on the tender, new growth in the recently burned patches, which encourages rotational grazing and prevents overgrazing. Because herds are confined to protected areas with limited space, population control is necessary. This is typically achieved through periodic roundups, health checks, and the relocation of excess animals to balance the herd size with the available habitat.