A Solution to Yellowstone's Bison Slaughter—And How You Can Help

Photo by Nic Minetor

Why did Yellowstone National Park capture and slaughter 1,400 of its famous bison during the winter of 2007-08?

And who has an excellent plan to make certain that this action need not be repeated?

The shocking slaughter was necessary, Yellowstone officials note, as part of a disease control initiative.  Yellowstone participates in the Interagency Bison Management Plan (IBMP), through which the park has agreed to keep bison separate from domestic cattle that graze on land outside the park in Montana. The separation is necessary because many bison carry the bacteria brucellosis—a disease that is harmless to bison, but can cause spontaneous miscarriages in pregnant domestic cattle.

During the winter, Yellowstone’s bison migrate outside of the park in their search for better forage, moving into private lands and potentially coming into contact with ranchers’ cattle. As the winter of 2007-08 was particularly harsh and food was in short supply, more bison wandered north than in other years.

Park staff members work on horseback to haze the animals back into the park, but if the bison persist in crossing the boundary, they must be captured and tested for brucellosis.  Bison that test positive may be scheduled for slaughter, or they may be quarantined as part of a research study on the bacteria. 

All of this sounds quite reasonable, until we see the staggering numbers this program produced in winter 2007-08.  Seven hundred bison perished because of a lack of food in an unusually harsh winter, or from predation (wolf kills)—all natural parts of Yellowstone life.  About 1,400 more—an astonishing figure when compared to previous years—were captured and sent to slaughter.

“When we test bison for exposure to brucellosis, anywhere between forty and sixty percent test positive,” said Al Nash, pubic affairs officer at Yellowstone National Park. “This doesn’t mean they’re all infectious.  But we’re in a situation where we do have a wild herd of animals that carries a disease that is infectious to cattle…. Because of this, there’s very limited tolerance for bison outside of park boundaries.”

By spring 2008, Yellowstone’s bison population had diminished by half, from 4,700 head to about 2,300 animals.  Nash noted that the bison meat, heads and hides are donated to tribal groups, so at least there is some small benefit to the operation—but this has never been an end in itself.  “Our goal is to see how we can increase tolerance for bison outside of Yellowstone,” he said.

Fraught with political controversy and rife with accusations from conservation groups that the park has not moved aggressively enough to find a solution, the slaughter has drawn national attention.  “We certainly hear a lot of simplified proposals from a lot of people,” said Nash.  “Wildlife management is part of our culture.  All large wildlife in North America is managed in some fashion: elk, deer, bighorn sheep, and bears. We are working with other agencies to move bison management forward.”

Thankfully, one of these efforts looks like a viable solution. The National Parks Conservation Association (NPCA) is raising $1 million to allow the bison to migrate up to nine miles north of the park onto the Royal Teton Ranch, where they can find the food they need to survive the tough Montana winter. The first $900,000 has been secured, but the foundation needs $100,000 to clinch the deal. 

NPCA officials have opened the campaign to the general public to close this final gap, and their materials state that 100 percent of each contribution will go directly to securing this habitat for the bison.

If you’d like to contribute to this effort, send donations of any size to Montana Fish, Wildlife and Parks c/o Sue Daly, 1420 East Sixth Avenue, Helena, MT 59620.  Write “Royal Teton Ranch” on your envelope to be sure it goes to the right place.

Yellowstone’s Nash reports that the 2008 breeding season already has repopulated the herd, with 3,000 bison now roaming the park.  “This is a very healthy and vibrant population,” he said.

With the help of the NPCA and a generous public, Yellowstone may finally subdue the winter threat to its bison.