Judge denies Yellowstone's request to stall bison lawsuits

“This court decision is a great step in the right direction — we need to base the management of our National Mammal on sound science,” said Mike Garrity, executive director of the Alliance for the Wild Rockies, in a statement.

3 Yellowstone lawsuits

Since being finalized, Yellowstone’s bison plan has been challenged in three separate lawsuits.

In its case, the state of Montana is arguing it wasn’t adequately involved in the development of the document and also wants the park to maintain a lower bison population.

Bozeman-based Cottonwood Environmental Law Center is seeking to halt the state’s lawsuit until the Custer Gallatin National Forest and the Animal Plant Health Inspection Service complete environmental reviews related to a 2018 lawsuit Cottonwood filed. The law firm argued that new science allows bison to be held for less time in quarantine to prove they are not carriers brucellosis, a disease that can cause pregnant ungulates to abort.

In their lawsuit, the Alliance for the Wild Rockies and Council on Fish & Wildlife argued the Park Service failed to incorporate the findings of a 2020 National Academies of Sciences, Medicine, and Engineering report regarding the disease brucellosis, as well as the U.S. Fish and Wildlife Service’s current consideration of bison as a threatened or endangered species due to its range being restricted.

Judge Morris consolidated the cases in 2025 to ease the administrative burden.

Montana said OK

Montana agreed to the stay. Cottonwood was not opposed if the feds agreed to address all of its issues and have an “enforceable timeline” for review.

Only Alliance for the Wild Rockies argued against the request, saying the SEIS could take years to complete and that there was no guarantee that the feds would consider any of the concerns Alliance raised in its lawsuit.

“Thus, proceeding with litigation is appropriate and necessary because it will result in a court order that will inform a supplemental EIS process,” Alliance argued.

Morris ruled in the Alliance’s favor.

“The SEIS makes no mention of addressing Alliance Plaintiffs’ claims,” he wrote.

Judge Morris also wrote that Alliance could “suffer hardship from a stay” given Yellowstone’s current management that the group argues has failed to use the best available science in determining to maintain bison capture and slaughter operations.

More analysis

In proposing to re-evaluate its bison plan, the Park Service said it plans to develop "one or more new alternatives" to the three that were evaluated in its 2024 plan.

"These new alternative(s) may incorporate elements previously dismissed from detailed analyses or include elements not previously considered," the agency previously stated.

"As part of the SEIS process, NPS will determine whether additional analysis of any issues raised in those lawsuits is appropriate, and if so, will include such analysis in the SEIS," the Park Service said.

Focus on elk, not bison

Yet the Alliance argued Yellowstone’s new plan does little to reduce the risk of brucellosis being transmitted to cattle, one of its main stated goals.

That’s because so far, all brucellosis outbreaks detected in livestock near the park have been traced to elk. Elk and bison carry the disease, which is transmitted through an infected animal’s birthing material. But only elk roam freely, while bison are restricted to areas just outside Yellowstone.

Despite this, Montana has argued bison are a greater threat to livestock because more bison have tested positive for exposure to the disease than elk.

To keep elk from infecting cattle, Montana tries to keep the animals separated through hazing, issuing kill permits and fencing off haystacks that attract elk to ag fields.

The best way to reduce brucellosis in livestock, the Alliance argued, is to focus more on elk, pointing to a 2020 national science study offering several suggestions.

The Park Service’s decision to continue to reduce Yellowstone’s bison herd through slaughter and transfer “entirely fails to consider the most important aspect of this problem,” the Alliance argued, saying managing bison alone is “futile.”

Consequently, Yellowstone’s environmental impact statement failed to analyze a “reasonable range of alternatives.”

Interestingly, last year Cottonwood requested that the state’s lawsuit be stalled while its grievances were considered. Montana argued against the request to have its lawsuit stayed accusing Cottonwood of trying to “hijack” the lawsuit for reasons unrelated to Montana’s complaints.