The National Park Service has released its preferred plan for managing Yellowstone National Park bison/NPS file
A proposed plan for managing bison at Yellowstone National Park has received plaudits from some conservation organizations, though it has its critics and leaves some questions unanswered about the future for the country's national mammal.
Under the preferred alternative contained in the final environmental impact statement (FEIS) released Friday, the National Park Service would aim for an annual Yellowstone bison population ranging between "about 3,500 to 6,000 animals after calving," continue to transfer bison to tribal lands via the Bison Conservation Transfer Program, and continue to allow both a "tribal treaty harvest" and public hunting outside the park to regulate numbers.
The plan also adheres to Interagency Bison Management Plan (IBMP)objectives to: 1) maintain a wild, free-ranging bison population; 2) reduce the risk of brucellosis transmission from bison to cattle; 3) manage bison that leave Yellowstone National Park and enter the State of Montana; and 4) maintain Montana’s brucellosis-free status for domestic livestock.
"The new bison management plan is an important next step as we work together to make sure Yellowstone bison continue to thrive with the Greater Yellowstone area, tribal lands, and other areas," saidMichelle Uberuaga, senior Yellowstone program manager for the National Parks Conservation Association. "We applaud the park’s commitment to expanding tribal cultural herds and will continue to work to ensure bison are managed in the same manner as other wildlife in the Greater Yellowstone Ecosystem—including ending the annual 'ship to slaughter' program. The plan is grounded in the best available science and commits to flexible management strategies that will allow bison to thrive within Yellowstone."
The issue of bison migrating out of Yellowstone and possibly spreading brucellosis to cattle herds in Montana long has been controversial and led to adoption of the IBMP in 2000 after that state in 1995 sued the federal government over fears bison were spreading brucellosis to cattle. However, research conducted in 2016 concluded that elk, not bison, infected cattle herds in Montana and, overall, posed a greater threat than bison to spreading the disease in the region. Nevertheless, Montana takes a much harsher view of bison entering the state than it does elk.
The challenges discussed in the FEIS reflect the cross-governmental intricacies of managing Yellowstone bison. Once the animals leave the park, they no longer are under Park Service jurisdiction but fall either under state control or the U.S. Forest Service if on national forest lands.Additionally, several tribes have treaty rights to hunt bison that leave Yellowstone and head onto the Custer Gallatin National Forest. Private landowners also come into play when bison move onto their properties, while non-governmental organizations that want to preserve Yellowstone bison also voice their concerns.
"This management plan is based on science and allows for bison to move freely outside of Yellowstone’s boundaries and into tolerance zones in adjacent national forest lands," said Chamois Andersen, Defenders of Wildlife’s senior representative for Rockies and Plains. "Smartly, it also includes increased capacity for the Bison Conservation Transfer Program, testing bison for brucellosis and transporting healthy animals of high genetic value to tribes across the U.S."
Disagreeing with both NPCA and Defenders of Wildlife is the Buffalo Field Campaign, a bison advocacy group that dates to 1997 and which long has opposed the Park Service's approaches to managing bison in Yellowstone. That group has said the FEIS should have contained an alternative "to manage wild bison like wild elk," and allow for bison to roam out of the park and onto "millions of acres of National public trust lands adjoining Yellowstone."
While the National Park Service could sign off on the FEIS's preferred alternative in early July, two pending matters could force the agency to revisit its chosen approach. The U.S. Fish and Wildlife has been asked to consider whether thereare two genetically distinct bison herds in the park — one in the center of Yellowstone and another on the Northern Range — and to decide whether Yellowstone bison should bedesignated as a threatened or endangered species under the Endangered Species Act.
Back in 2014,the Buffalo Field Campaign and Western Watersheds Project petitionedthe Fish and Wildlife Service to extend "threatened" or "endangered" designation under the ESA to Yellowstone's bison. In a somewhatlengthy petition of more than 60 pages, the groups argued that Yellowstone's bison are "the largest remnant population of the Plains bison that ranged across much of United States until it was eliminated post-settlement."
While the Fish and Wildlife Service opted in December 2015 not to extend such protection, holding that there was no "substantial scientific or commercial information" to justify such a designation and that bison numbers in the park were growing and so it wasn't going to do a "status review" on whether bison were doomed, in January 2022 the Buffalo Field Campaign and Western Watersheds Project renewed theirlegal battle over that question. That prompted a federal judge to order USFWS to re-examine, for a third time, the groups' petition.While U.S. District JudgeRandolph D. Moss at the time did not rule one way or another on whether Yellowstone's bison merit ESA protection, he did say the Fish and Wildlife Service needs to do a better job of explaining why it doesn't think they do. He also expressed some consternation thata case brought in 2014has not been satisfactorily handled by the agency.
In June 2022 the Fish and Wildlife Service announced it wouldtake another lookat the question. Two weeks ago the Buffalo Field Campaign, Western Watersheds Project, Friends of Animals notified the Fish and Wildlife Service it would sue the agency for delaying a decision on the listing.
As for whether there are two genetically distinct bison populations in the park,the Buffalo Field Campaign and Western Watersheds Projectfound a study suggesting that Yellowstone's "central" and "northern" bison herds are two separate herds that are "genetically distinct" and so should be preserved. A federal judge in 2018 directed the Fish and Wildlife Service to take a closer look at that contention, which could have a significant impact on the site of Yellowstone's bison herds.
The study in question was by Dr. Natalie Halbert, who theorized that the two herds are genetically distinct. Digging into her study, U.S. District Judge Christopher R.Cooper wrote that the IBMP's population goal of 3,000 bison in Yellowstone could be too low to support two genetically distinct herds.
"Since other studies have suggested that around 3,000 bison are needed to ensure a herd’s survival, this suggests that the 3,000 bison population target for both herds is too low to ensure that each herd will survive," he noted.
While the Fish and Wildlife Service again disagreed with the conservation groups, a federal judge in January 2022 again said the federal agency didn't properly examine the issue.
"Although the Service has twice failed toemploy the correct evidentiary standard in reviewing the long-pending petitions, there is noreason to believe that the agency is acting in bad faith or that it is unprepared to adhere to theCourt’s decision,"U.S. District JudgeRandolph D. Moss wrote in that 2022 ruling. "It is concerning, to be sure, that over seven years have now passed since the2014 petition was filed. But it remains unclear whether sufficient basis exists to proceed to thenext stage of the ESA process, and, in light of the substantial amount of work done to date, theService should be able to answer that question promptly."
Back at NPCA,Uberuagatold the Traveler on Friday that, "I believe that a positive listing decision from USFWS would require a recovery plan that could supersede the park's plan and would definitely limit their flexibility in management." However, she added that she doubted that a listing under the ESA "was likely."
Neither the Park Service nor the Fish and Wildlife Service addressed the Traveler's questions regarding how a possible ESA listing might impact Yellowstone's preferred bison management plan. However, in the FEIS park staff noted that the Fish and Wildlife Service plans to take up the bison issue during fiscal 2026, which begins in October 2025.
"At this time, no decision has been made regarding the [ESA] listing of Yellowstone bison and for this reason would not influence NPS management actions. If the status of Yellowstone bison changes, the NPS would work closely with FWS on the management of this species," the FEIS stated.
