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Know the West

Judge: Agency cherrypicked science for bison management

Amid protests, Fish & Wildlife has been ordered to reexamine protections for the iconic Yellowstone beast.


Before dawn on a frigid morning earlier this month, two members of the activist group Wild Buffalo Defense locked themselves to part of an enclosure at Yellowstone National Park’s Stephens Creek Capture Facility. Bison held at the facility are tested by park staff for brucellosis, and hundreds are destined for slaughter as part of the Park Service’s annual herd reductions. The demonstrators hoped to prevent the continued killing of Yellowstone bison and to protest a recent decision not to allow the transfer of bison to the Fort Peck Reservation, in Montana. As activists continue to fight the culling of Yellowstone bison, a recent court decision could help them get what they want: stronger protections for the park’s herds.

Bison numbers are reduced through slaughter and hunting each year for a couple of reasons. Park managers say they need to keep the numbers low or the bison will overgraze in the park. And some local interests want bison to stay off the range and ranches outside the park because of concerns about the spread of brucellosis, a disease that causes cattle abortions, or because bison compete with cattle for forage and can cause property damage.

A District Court judge has now ruled that the U.S. Fish and Wildlife Service must reevaluate its 2015 decision not to consider Yellowstone bison for a threatened or endangered species listing. That means bison could still be granted protections under the Endangered Species Act. If that happens, federal agencies would be required to protect the bison and likely have to alter their culling practices. The Jan. 31 decision directs Fish and Wildlife to redo its conservation assessment of Yellowstone’s iconic herbivore “using the proper standard” for scientific review.

Bison graze in Yellowstone National Park.

The suit against Fish and Wildlife argued the agency did not properly consider all of the available scientific literature, presented by Buffalo Field Campaign and other environmental groups, in a petition to have Yellowstone bison listed under the Endangered Species Act. Judge Christopher Cooper ordered the agency to take a second look at protections for bison, writing that it cannot “simply pick and choose between contradictory scientific studies.”

The decision found that Fish and Wildlife improperly dismissed a 2012 study led by Texas A&M researcher Natalie Halpert, that found evidence of two genetically distinct herds of bison in Yellowstone. The agency’s decision preferred the conclusions of National Park Service biologists Patrick White and Rick Wallen, who said that distinctions between the central and northern herds were artificial and shouldn’t determine conservation efforts.


Current management plans for Yellowstone bison set the target herd size for the entire park at around 3,000, the baseline for a viable bison population. If the central and northern herds are genetically unique enough to merit conservation, as Halpert’s study finds, then both herds should be managed with a target population of 3,000 each —­­­­­­­­­ doubling the target population of bison in Yellowstone.

The latest report on bison populations in the park, published in September 2017, found the central herd had less than 1,000 members. Despite the low population, more than 80 bison have been killed this winter along the western boundary of Yellowstone, where most bison are from the central herd.

In response to emailed questions about the bison status review, Roya Mogadam, Fish and Wildlife’s deputy assistant director for external affairs for the Mountain Prairie Region, wrote: “We are currently determining the best course of action to address the Court’s remand.”

Bison loaded into a trailer at Yellowstone's Stephens Creek Capture Facility. Hundreds of bison are shipped for slaughter from the facility each year.

Michael Harris, the wildlife law program director for Friends of Animals, which brought the case against the agency, along with the Buffalo Field Campaign and Western Watersheds Project, said the organizations are fairly confident the case will lead to a yearlong review of the species protection status for bison, which would include opportunities for public input and a more rigorous review process. “This process could lead to better protections, and it doesn’t matter for us if it’s through an endangered species act designation or just better protections from the current managing agencies,” Harris said.

Because Endangered Species Act protections would require new management plans, the agency is experiencing political pressure not to list the species, Harris said. If the bison were listed under the act, the protections provided by federal law would override the authority of the Interagency Bison Management Plan, a coalition of state, federal and tribal stakeholders.

As Fish and Wildlife evaluates options for future protections of Yellowstone’s bison, direct action protests continue at the Stephens Creek Facility. Ten days after activists locked themselves to the squeeze chute at the facility, two more activists from Wild Buffalo Defense locked themselves to 55 gallon barrels to block traffic to the facility. Darrell Geist, the habitat coordinator for the Buffalo Field Campaign, said: “People of conscious feel compelled to act now and not wait for the government to act.”

Carl Segerstrom is an editorial intern at High Country News.