Bison constitutes two subspecies: wood bison (Bison bison athabascae) and plains bison (Bison bison bison). For simplicity, I’ve treated North American bison conservation efforts as one thread; however, the biology and politics of protecting the two subspecies was much more complex than I summarize here.

In fact, governments, biologists, and conservationists struggled with maintaining the genetic purity of different subspecies and herds. According to a 2016 paper titled “Genetic analyses of wild bison in Alberta, Canada: implications for recovery and disease management” published in the Journal of Mammalogy, there is “acceptance that for bison living within Wood Buffalo National Park and Elk Island National Park, there are no ‘genetically pure’ wood bison and that all individuals tested from these areas fall into a spectrum of genetic admixture between wood and plains bison.” To put the numbers in context, Alberta’s Elk Island National Park has the most genetically pure herd of wood bison, numbering about 300 animals.

An Abbreviated History of Bison

Canada and the United States are both entangled in the destruction and subsequent conservation of bison in North America. As many people will be familiar, bison once numbered in the tens of millions and ranged throughout most of North America. Throughout the 1800s, bison were hunted to near-extinction in the United States and Canada by market hunters and as part of efforts to destroy Indigenous cultures.

In 1872, the United States established Yellowstone National Park, in large part to protect habitat for bison. In Canada prohibited hunting for wood bison in 1893, established the first herd of bison in Banff National Park in 1897, and created Wood Buffalo National Park in 1922 to protect what remains the world’s largest free-roaming herd of bison (now numbering around 3,000 individuals that represent a range of hybridization between wood bison and plains bison).

By somewhere around 1897, bison were all but gone as a free-roaming species. For both a thorough and thoroughly fascinating history of Canadian and American bison conservation, check out the report Like Distant Thunder: Canada’s Bison Conservation Story, written by Lauren Markewicz.

Reintroducing Bison

Elk Island National Park has played a key role in Canadian bison conservation. In 1907, through a convoluted series of purchases, deaths, bequeathments, and more purchases, the Canadian government purchased about 716 plains bison from Montana and moved them to Elk Island National Park, and since then they have served as a source herd for plains bison reintroductions. Since the early 1900s, Yellowstone National Park has really been one of the cornerstones of bison conservation and a source population to reintroduce herds to other parts of their former U.S. range. Yellowstone National Park now has an estimated 5,000 bison.

In the last number of years, it has been great to see largely positive news coming out around bison. For example, in Banff National Park in Alberta, Canada in 2017, Parks Canada moved 16 bison to an enclosure for a soft release. In 2018, after successfully reproducing on their own, Parks Canada released 31 bison as a free-roaming herd and continue to sustain themselves.

We’re seeing similar reintroductions onto the landscape in other parts of the United States from Yellowstone herds. One of the main challenges with bison reintroduction is brucellosis. Brucellosis is a bacterial disease that domestic cattle brought to the Yellowstone area in the early 1900s. It affects ungulates like cattle, elk, and bison. While there has never been a confirmed transmission of brucellosis from wild bison to domestic cattle, it is possible for bison to transmit the disease to local wildlife populations, including other bison herds. To protect against brucellosis transmission, many bison are sent to slaughter each year or hunted to maintain a target herd size to prevent overgrazing. Any bison that are transported out of Yellowstone must undergo prolonged and rigorous testing to make sure that they are free of brucellosis.

New Transfers in Montana

In 2019, the National Park Service, the State of Montana, the Animal and Plant Health Inspection Service (APHIS), and Fort Peck Assiniboine and Sioux tribes started the Bison Conservation Transfer Program. The program captures and isolates bison so that they can go through repeated testing for brucellosis and then used to start conservation herds elsewhere. Since 2019, 182 bison have gone to the Assiniboine and Sioux Tribes and used as a source population for other introductions. Out of those 182 bison, 82 were transferred to the InterTribal Buffalo Council and the Council then distributed them to 18 other Tribes across 10 States.

This latest round of good news came in January 2022. On January 12, the Bison Conservation Transfer Program transferred another 28 Yellowstone bison to the Fort Peck Indian Reservation. Those 28 bison were captured in March 2020 and completed the first two phases of the brucellosis quarantine protocol. In that group of 28, there were 20 males and then a small family group with one male, four females, and three calves.

Currently, there are still 67 animals in the transfer program and the program intends to enter another 80 to 120 new animals this winter for further transfer.

This is a great program that underscores the connections between the deeply entwined social, cultural, and environmental aspects of conservation. The InterTribal Buffalo Council emphasizes that this program is really about also preserving historical, cultural, traditional, and spiritual relationships. The InterTribal Buffalo Council says that “to re-establish healthy buffalo populations on tribal lands is to re-establish hope for Indian people. Returning the buffalo to Tribal lands will help heal the land, the animal, and the spirit of the Indian people.”

Conclusions

While the hunting community often holds William Temple Hornaday as a major contributor to bison recovery, his legacy is sometimes difficult to celebrate alongside his rampant racism and support for eugenics. However, numerous other government and non-government agencies and programs continue to work tirelessly to restore and manage a species that has deep ties to the ecologies and cultures of this continent.

Bison reintroduction projects such as the Bison Conservation Transfer Program and the successful reintroduction of bison into the Yukon from 1988-1992 (that herd began with about 170 animals and has now grown to over 1,500) are putting an animal back on the landscape and re-establishing important human-animal relationships that have been celebrated and existed for generations and thousands of years throughout North America.