(Photo by Eric Hope - National Park Service)

Bison on the North Rim of Grand Canyon National Park.

By virtue of weighing about 2,000 pounds apiece, bison are used to creating a stir. In Grand Canyon National Park, how to manage bison and how many there should be has been causing controversy. There are an estimated 400 to 600 bison in the Kaibab National Forest and Grand Canyon National Park.

That led to the production of a new report by a team of nine wildlife biologists.  The report concluded bison are native to that area and have been there for thousands of years.

Glenn Plumb, is the acting chief of science and resource management at the Grand Canyon and contributed to the report.