Yellowstone Takes Next Step to Maintain Bison Migrations Outside the Park

Yellowstone National Park staff drove 23 bison into a fenced pasture on park land northwest of Gardiner, Montana, on Tuesday, January 4, marking a new phase in the decade-old Interagency Bison Management Plan. Soon, 25 bison will be moved onto land in the nearby Gallatin National Forest. It's the next step in the plan conceived by eight national, state, and tribal agencies to conserve bison migratory behavior, manage a free-ranging bison population between the park's northern boundary and Yankee Jim Canyon in the Gardiner Basin, reduce the risk of brucellosis transmission to cattle, and maintain Montana's brucellosis-free status.

More bison will soon be driven to the fenced pasture near Stephens Creek, where all will be tested for brucellosis, the bacterial infection that causes abortions in bison and cattle. Twenty-five healthy animals will be marked, fitted with monitoring devices, and released into the Gallatin National Forest, where they'll be allowed to remain until spring. The bison remaining at Stephens Creek will be re-released into the park.

The Yellowstone area bison herd ranges from 2,500 to 4,500. About 60 percent of the females are seropositive for brucellosis. Several hundred bison migrate to low-elevation winter ranges along the north and west park boundaries each year, the result of natural behavior, annual bison populations, and annual snowpack depths. Besides disease fears, some migrating bison have had to be removed because of private property damage and human safety concerns in Gardiner, Corwin Springs, and West Yellowstone, Montana. 

Eventually, the bison plan will allow up to 50 and then 100 bison onto the same landscape. The Stephens Creek area is closed to the public for safety reasons, but information on the plan is available at the park's Albright Visitor Center in Mammoth Hot Springs, Wyoming. The plan and past reports are at http://ibmp.info/