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Progress to Date: Bison Restoration


The Reserve's growing and healthy bison herd is the result of a decade of dedication and hard work by collaborators, scientists, veterinarians, donors, and staff. At a glance, here's how the herd has progressed:

2005: First Bison Introduced to American Prairie Reserve

On a cold and rainy night, not long past midnight on October 20, 2005, 16 bison stepped back onto the Montana prairie after an absence of more than 120 years. APR and World Wildlife Fund staff watched as the bison began to graze in their holding pasture, acclimating to their new home before being turned out onto American Prairie Reserve. Several of these bison were pregnant cows. After much waiting, the APR Reserve Manager was proud to report the births of five baby bison on the Reserve in April 2006.


2006-2009: A Growing Herd

From 2006 to 2009, the herd continued to grow with the addition of new arrivals from Wind Cave National Park and The Nature Conservancy of South Dakota. Additional calves have been born on American Prairie Reserve each spring since 2006.



In early 2010, we greatly increased the size of our herd with the addition of 94 bison from Elk Island National Park in Alberta, Canada. The ancestors of these bison originally came from Montana and were part of the Pablo herd, the largest herd of bison left in North America in the early 1900s, after they were largely extirpated from the Great Plains. The Pablo herd was privately owned until the Canadian government purchased the bison in 1907. The return of these bison to Montana continues to be a historic homecoming – 71 additional bison calves were transferred from Elk Island to American Prairie Reserve in early 2012 and another 73 calves were relocated in early 2014.

2012 Bison Transfer from Canada's Elk Island National Park to American Prairie Reserve


With the rapid population growth of the herd, we reached the carrying capacity of the Sun Prairie region in 2015 and will be expanding the herd onto our 22,000-acre Sun Prairie North property in 2016. As Sun Prairie North consists of deeded, State of Montana, and BLM lands, BLM officials currently are reviewing our request for bison grazing on that property.