River Runners and Bison

If bison could manage to get through fences, like pronghorn antelope, rabbits and coyotes do, you might just see a lot more bison on federal lands than you do.

Bison have been in North America for well over 160,000 years. They got to the Americas well before we as a species did. Records of bison bones, bison poop and even bison rock art abound on the Colorado Plateau. So when Grand Canyon National Park talks bison, Grand Canyon river runners, backpackers, and park lovers sit up and pay attention.

Bison? Grand Canyon National Park? Yup. Before the creation of the National Park Service in 1916, the North Rim of the Grand Canyon was recognized as a place where bison might recover. At the time, there were less than 200 bison on the planet.

Congress established the Grand Canyon Forest Preserve on the Kaibab Plateau, including the North Rim of Grand Canyon, in 1906. A report to the U.S. Congress titled the Protection of Wild Animals in the Grand Canyon Forest Preserve, listed bison as a wildlife species that should be maintained on the Kaibab Plateau. The Kaibab Plateau was described as “ideal for buffalo [Bison], deer and other wild game” and was “to be recognized as a breeding place therefore.

The concept of a Grand Canyon Bison Preserve was short lived. When the United States Forest Service was created, the Kaibab Plateau began to be managed for timber harvesting and cattle grazing. There was no place for the native bison, so they were moved out of the area. Except, 15 to 20 escapees remained and by 1927, had increased to about 100. Those bison were sold to the State of Arizona and were moved to the margins of the forest, down in the House Rock Valley, where the range was poor. Good fencing kept the bison in place. Think of it as bison prison.

But these bison were survivors. After all, the natural range for bison includes the desert southwest. Did you know bison like woodlands? Yes, they do, not just open prairie. And, they can survive on poor rangeland.

In the late 1990’s through the early 2000’s the bison “escaped” from their prison on the House Rock Valley and headed upslope to the heavy forests and meadows of the Kaibab Plateau. Then, the bison discovered that if they were within the borders of Grand Canyon National Park, no one would shoot them. Hunting is not allowed in National Parks.

The result has been spectacular. Without any management by anyone, the bison population has increased from 100 to almost 600 bison.

The trouble is, the animals that can keep bison populations in check are no longer around. We killed off the sabre tooth cat and the dire wolf over 10,000 years ago. So the Grand Canyon bison population is now exploding.

Grand Canyon National Park planners are well aware that any species, if left unchecked, can eat itself right out of food and water supplies, and hurt the environment in the process. Fortunately, the Park Service is allowed to cull native species that grow too big in numbers without natural predators.

Grand Canyon National Park decided the park needed a Bison Management Plan in 2014. This excellent idea required an Environmental Impact Statement. Doing these plans is costly, and they can be many hundreds to thousands of pages long.

What makes the Bison Management even more complex is that bison like to move around. If they weren’t hunted, the bison would leave Grand Canyon and move out into the Kaibab National Forest. That means Grand Canyon National Park would have to work with the United States Forest Service (USFS), Bureau of Land Management (BLM), and Arizona Game and Fish Department (AZGFD). Plus all the cattle ranchers that use USFS land to graze their cattle.

Soon after the Park Service started a Bison Management Plan in 2014, they stopped it. Getting the USFS, BLM, AZGFD and all the cattlemen together to help out the bison, and provide funding to park planners, was just too much of a heavy lift. Sadly, the Park Service abandoned the planning process.

But the bison kept doing what bison do, and their populations continued to grow. In 2016, Grand Canyon National Park started a Bison Reduction Environmental Assessment. It was released in May and can be found HERE.

The Herd Reduction Environmental Assessment includes lethal and non-lethal culling to keep the bison population at “200 bison or less.” Except 200 bison or less is what the House Rock bison prison had been managing for the last 90 years. Once the Grand Canyon bison are corralled into a pen and trucked away back to the House Rock bison prison, or shot on site in the park as part of a culling program, they will not be invited back.

Bison are America’s National Mammal and are the largest native animal in North America. It’s easy to build a fence and keep them out. But bison deserve better than that, especially on Federal land, where native species are to be protected.

The North Rim encompasses 97,000 acres. The House Rock Valley has 54,000 acres. The House Rock herd was managed for around 100 bison post hunt (not far from 200 or less), so managing the North Rim for 100 bison should be feasible until the Park long term planning is done.

The National Park Service has recognized a potential large landscape of about 215,000 acres on the Kaibab Plateau for possible future management of the herd. This includes lands in Grand Canyon National Park and the Kaibab National Forest. Let’s keep a small herd in Grand Canyon National Park until the larger landscape is created.

Here is some background information:

Grand Canyon National Park Bison Management Plan/ Environmental Impact Statement [HALTED IN 2016]

EIS Frequently Asked Questions

EIS Frequently Asked Questions (Updated April 2016)

Grand Canyon National Park Initial Bison Herd Reduction Environmental Assessment 2017

Initial Herd Reduction EA (2017)

Arizona Department of Game and Fish

Bison Hunter Packet Spring/Summer (2017)

Scientific Papers

Bison of the Grand Canyon Region: An Overview Assesment (Mead 2002)

Arizona Bison Genetics: Verifying Origins (Wakeling 2005)

American Bison Report (2010)


Late Pleistocene and Holocene Bison of Grand Canyon and Colorado Plateau: Implications from the use of Paleobiology for Natural Resource Management Policy (Martin 2014)

Grand Canyon Bison Nativity, Genetics, and Ecology: Looking Forward (Plumb 2016)

Late Pleistocene and Holocene Bison of the Colorado Plateau (Martin 2017)

RRFW Public Comments On Bison Management

June 3, 2014

April 3, 2016

June 14, 2017

If you have additional questions about Grand Canyon Bison, contact Tom Martin at