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Montana files lawsuit against Yellowstone’s plan to increase bison herd

Three bison cross a road with cars stopped either direction.
Hannah Habermann
/
Wyoming Public Media

This story is part of our Quick Hits series. This series will bring you breaking news and short updates from throughout the state.

Montana is suing Yellowstone National Park over its plan to increase the park’s bison herd.

The plan the park adopted this summer allows the herd to grow to up to 6,000 animals. The ten year average of the park’s herd is around 5,000.

Montana Gov. Greg Gianforte along with the state’s Department of Fish Wildlife and Parks and Department of Livestock filed the lawsuit in district court on New Year’s Eve. The state had been threatening to sue since the early stages of the plan's development.

The state of Montana wants the park to maintain 3,000 bison. This was a population target included in a court mediated settlement following a previous lawsuit that Montana filed 30 years ago.

The current lawsuit claims that growing the population would increase the possibility of bison outside of the park transferring a reproductive disease called brucellosis to cattle. There has not been a documented case of this happening between Yellowstone bison and cows.

The lawsuit alleges that the park violated federal law by not including Montana in talks while it developed the new bison plan, among other violations.

“The National Park Service has repeatedly and consistently failed to engage with the State in a meaningful and transparent manner as required by law throughout the planning process,” Gianforte said in a press release. “NPS has not given us a fair shake and has ignored concerns raised by the State. We will always defend our state from federal overreach.”

In a July letter responding to the state's concerns with the park's bison plan, Yellowstone National Park Superintendent Cam Sholly wrote that the park is trying to balance the state's concerns with public opinion and scientific factors.

"Your recent letter called our offer to meet with you again ‘disingenuous,’ which is unfortunate. You've had multiple visits from me, senior DOI leadership, and Yellowstone's wildlife team, at your request," Sholly wrote.

In a previous interview with Wyoming Public Radio, Sholly said the park is keeping the herd at the same size it’s been for the past 10 to 15 years and that reducing it to 3,000 would require slaughtering a massive amount of bison each year.

Montana also claims that the increase in bison is degrading habitat in Yellowstone.

In the lawsuit, the state said it would like to see more analysis on how transferring Yellowstone bison to tribal nations could impact other wildlife. The new plan prioritizes transferring more bison to tribes and tribal hunting over slaughtering bison.

Montana wants Yellowstone’s bison plan blocked and sent back to park administrators to draft a new plan.

Editor's note: This story has been updated to include a response from Yellowstone National Park.

Olivia Weitz is based at the Buffalo Bill Center of the West in Cody. She covers Yellowstone National Park, wildlife, and arts and culture throughout the region. Olivia’s work has aired on NPR and member stations across the Mountain West. She is a graduate of the University of Puget Sound and the Transom story workshop. In her spare time, she enjoys skiing, cooking, and going to festivals that celebrate folk art and music.

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