Yellowstone bison plan calls for culling 600-900 animals
By Moosetrack Megan

Posted: January 8, 2016

Released Tuesday by Yellowstone National Park


Members of the Interagency Bison Management Plan (IBMP) have signed a winter operations plan that aims to reduce the current population of 4,900 animals. Because the Yellowstone bison population has high reproductive and survival rates, it will be necessary to cull 600-900 animals to offset the population increase expected this year. IBMP managers will decrease the population using two methods:

(1) Public and tribal hunting outside the park, and
(2) Capturing bison near the park boundary and then transferring them to Native American tribes for processing and distribution of meat and hides to their members.
Bison are a migratory species and they move across a vast landscape. When they are inside Yellowstone, they have access to all habitat. But in the winter, when some bison migrate to lower elevations outside the park in search of food, the surrounding states and some private landowners don’t offer the same access to habitat. Wild bison are only allowed in limited areas outside of Yellowstone because some are infected with the disease brucellosis that can be transmitted to cattle. Also, there are human safety and property damage concerns in some areas. The size of the population and the level of tolerance outside the park are two issues often debated by the IBMP partners and their constituents.
“Many people are uncomfortable with the practice of culling bison, including the National Park Service,” says Yellowstone National Park Superintendent Dan Wenk. “The park would gladly reduce the frequency and magnitude of these operations if migrating bison had access to more habitat outside the park or there was a way to transfer live bison elsewhere.”
Currently, it is against state and federal laws to move any wild bison exposed to brucellosis anywhere except to approved meat processing or research facilities. The park is currently studying the feasibility of developing quarantine facilities for bison, which would allow animals that repeatedly test negative for brucellosis to be sent alive to other public, private, or tribal lands for conservation, hunting, or food production.
Capture operations will occur at the Stephens Creek facility near the park’s North entrance. This facility is operated on behalf of all IBMP partners to meet population reduction objectives. For safety reasons, the facility is closed to the public year-round. Under this year’s IBMP operations plan, capture will begin no earlier than February 15, 2016 and will cease no later than March 31, 2016.
In 1995, Montana sued the National Park Service because bison were migrating out of the park onto state lands. A court-mediated settlement was reached in 2000 creating the Interagency Bison Management Plan (IBMP).Today, the park and seven other partners (listed below) implement this plan, which was approved by the secretaries of the Interior and Agriculture and the Montana governor.
The park and the state of Montana are working together to update the current bison management plan (IBMP). While the existing plan has been effective at preventing brucellosis transmission and maintaining a viable population, the park believes a new plan is needed. There is new data about general biology and disease prevalence, and public opinion is shifting toward more tolerance for bison in Montana. You can find more information about this planning process at the NPS PEPC website at .
The cooperating agencies operating under the IBMP are the National Park Service, the U.S. Forest Service, the Animal and Plant Health Inspection Service, the Montana Department of Livestock, the Montana Department of Fish, Wildlife and Parks, the InterTribal Buffalo Council, the Confederated Salish and Kootenai Tribes, and the Nez Perce Tribe.
Information on the IBMP is available online at Additional information about Yellowstone bison and their management can be found at
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