× Thanks for reading! Log in to continue. Enjoy more articles by logging in or creating a free account. No credit card required. Log in Sign up {{featured_button_text}}

Images of bison don’t pop into mind when we think of Grand Canyon National Park, but the Arizona Game and Fish Department’s bison-cattle hybrid herd, introduced to the Kaibab Plateau in the early 1900s, has rapidly become a major headache to park management.

Buffalo Jones introduced bison to the plateau in 1905 as an experiment to cross them with cattle and produce a manageable herd. The hybrids quickly migrated to lower elevation grasslands in House Rock Valley. Jones abandoned the idea and sold animals he could not capture to a rancher, who eventually sold them to the State of Arizona.

The State signed an agreement with the Forest Service, Bureau of Land Management, and local stockmen to “keep the buffalo confined to their designated range on the Kaibab National Forest.” For nearly 50 years, the State kept them within the 50,000 acres and allowed hunting to maintain herd size. In the late 1990s, poor range conditions and a lack of fence maintenance influenced movement of the herd onto the Kaibab Plateau and into Grand Canyon National Park. The Park Service made several attempts to thwart the bison-hybrid herd from becoming residents. Rather than acknowledge a developing problem, the State established hunting regulations that caused hunting pressure on the bison-hybrids, moving them farther into the park. The population has now grown significantly to more than 600 animals.