Yellowstone National Park Superintendent Suzanne Lewis announced today that bison have continued to migrate near Stephens Creek along the northern boundary of the park, and capture operations are continuing as part of the Interagency Bison Management Plan (IBMP). The IBMP, signed in December 2000, brings together three federal and two state agencies whose goals are to preserve a viable, wild population of Yellowstone bison; reduce the risk of transmission of brucellosis from bison to cattle, maintain the brucellosis class-free status for the state of Montana; and protect human life and/or private property. The agencies involved in IBMP include the U.S. Department of Interior's National Park Service, U.S. Department of Agriculture's Forest Service and Animal and Plant Health Inspection Service, and the State of Montana's Departments of Livestock and Fish, Wildlife and Parks.

Under the IBMP, a variety of methods are used along the north and west boundaries of the park to manage the distribution of bison and to maintain separation of bison and cattle on public and private lands. The IBMP also allows for some bison to remain on certain public lands adjacent to the park where cattle are not grazed.

In the first phase of management, the park hazes bison approaching the north boundary to keep them inside the park and away from cattle grazing adjacent to the park. However, after attempts at hazing the bison become ineffective and unsafe, it may become necessary to begin capturing the animals. Hazing has occurred over the past several weeks on numerous occasions. Hazing will continue when feasible, but capture operations may also continue.

On Tuesday, February 24, 2004, approximately 54-57 bison (a group of 12 early in the day and an additional group of 42-45 later in the day) were captured at the Stephens Creek facility. As with a group of 33 bison captured at the Stephen Creek facility on February 21, 2004, the bison will be held and tested for exposure to brucellosis. Bison testing negative will temporarily be held (up to 125 bison) for release back into the park in the spring. Any bison that tests positive for brucellosis exposure will be consigned to the State of Montana for transport to slaughter.

The group of 33 bison captured on February 21 were tested for exposure to brucellosis on Tuesday, February 24. Seven bison (1 yearling, 5 calves, and 1 adult female) tested negative for exposure to brucellosis and are being held at the Stephens Creek facility. As called for in the IBMP, the yearling and calves were vaccinated as part of a long-term brucellosis vaccination program. Vaccination is expected to reduce the sero-prevalance rate of brucellosis in bison. The 26 bison that tested positive for exposure to brucellosis were loaded onto trucks and taken to slaughter facilities on Wednesday, February 25, 2004. Meat, heads and hides of bison taken to slaughter will be donated to Native American groups/individuals or social service organizations.

An early winter count shows approximately 4,200 bison in the population.

Information provided by the NPS