Yellowstone bison plan calls for larger population

The National Park Service is finalizing plans to increase bison numbers in Yellowstone National Park and transfer some bison to tribes

Yellowstone National Park is on the verge of finalizing new management plans for bison in the park that will likely aim to keep the total population around where it has been over the past decade and prioritize utilizing a program to transfer bison to Native American tribes and more tribal hunting to manage the population.

The National Park Service’s final environmental impact statement for bison management was published Friday in the Federal Register, kicking off a 30-day waiting period before the National Park Service’s record of decision on the plans is finalized.

The plan recommends a bison population of from 3,500 to 6,000 animals depending on the season – in line with more recent populations. After a record 1,175 of the animals were killed by hunters outside the park during a particularly bad winter of 2022-23, conservation groups have pushed to increase herd sizes despite pushback from the State of Montana.

The publication of the document comes more than two years after the National Park Service first started the National Environmental Policy Act process for management changes in January 2022.

The draft environmental impact statement and management plan was published last August, and the NPS received more than 27,000 comments, including pushback from Montana Gov. Greg Gianforte and members of his cabinet that continues following the release of the final plan.

But officials with the Intertribal Buffalo Council, a member of the Interagency Bison Management Program that includes 80 tribes from 20 states, said Tuesday that they believed the preferred plan from the NPS is a good one and a way to allow the transfer program and tribal treaty hunting to continue.

“We’re on the same page of conserving those animals. We believe the park can accommodate a great number of animals, and then what they can’t accommodate, we believe should be translocated to the tribes,” said ITBC attorney Majel Russell.

The final plan changed little in terms of herd size goals from the draft version released last year. The three alternatives the NPS will have to choose from all would require the park to keep a minimum of 3,500 bison after calving, but maximum herd sizes range from 5,000 to 7,000.

The document says the park service’s preferred alternative is Alternative 2, which would also have park officials try to keep the Bison Conservation Transfer Program operation at full capacity. The program would bring in from 100 to 300 bison each year, which would be sent to Native American tribes in Montana and other states once they go through the quarantine protocols for brucellosis.

Brucellosis is a bacterial disease that is present in about 60% of adult female bison and many elk in Yellowstone that can cause abortions in pregnant animals and can spread to cattle. The park says about 10% to 15% of the female bison can transmit live bacteria to other animals.

For decades, Montana has resisted expanding the bison population in Yellowstone to try to prevent the bacteria from spreading to cattle, with the original thought being bison were more likely to spread it to cattle than other animals.

But there has still been no documented transmission of brucellosis from Yellowstone bison to cattle living nearby but outside the park, while there have been 27 documented cases of the bacteria spreading from elk to cattle since 1998, according to the plan. But there are few, if no, currently feasible options to vaccinate the animals on a large scale.

While the Interagency Bison Management Plan team – made up of federal, tribal and state agencies – has adapted the 2000 plan for bison management several times in the 24 years since, the new plan accounts for “new information and changed circumstances” since then, according to the National Park Service.

The plan says that information shows keeping the total population of the two herds within the park between 3,500 and 7,000 is preferred.

“This range is sufficient to sustain the important ecological role bison play in terms of manipulating plant communities; redistributing nutrients across the landscape; and providing meat for predators, scavengers, and decomposers,” the plan said.

Filling the transfer program for animals that go to the tribes each year would be the priority. The plan says the park service would recommend caps on hunting limits to ensure no more than 25% of the population is removed each year.

The preferred alternative also says the park service would have to adapt the plan based on each winter’s conditions, and possibly more often if climate change or other factors change winters in Yellowstone and the bison’s migratory habits.

This past winter, for instance, there were no bison seen in the Gardiner basin at all until the first week of March, and at the end of that month, according to IBMP data, only five had entered the Bison Conservation Transfer Program, while 26 were harvested by hunters from tribes and the state of Montana. Most tribes had not successfully hunted any bison this past winter as of March 28.

But the winter before, which was colder and snowier than recent years, there were 1,175 bison harvested by hunters, most of them tribal, and 282 bison put into the conservation transfer program. The hunt irked conservation groups who want to see more bison in the park, as well as people living near Gardiner who said the gut piles were attracting carnivores and hunters were at times sending rounds close to their homes.

The preferred alternative under the plan also notes that the park service will have to keep in line with Montana’s standards for the number of bison allowed into tolerance zones outside the park, which is not clearly defined but believed to be several hundred animals, according to the document.

Gianforte, along with Fish, Wildlife and Parks Director Dustin Temple and Department of Livestock Executive Director Mike Honeycutt, last year threatened the park service with modifying or pulling out of the 2015 agreement on the tolerance zones over the draft environmental impact statement, saying they wanted no more than 3,000 bison in the park and for a brucellosis vaccination plan to be included in the assessment and plans.

But the plan says doing so is not currently an option. It says eradicating brucellosis would mean the park service would have to capture, test, then vaccinate or slaughter “tens of thousands of elk,” which it says most people would consider “unacceptable or impossible at this time.”

“The NPS based this conclusion on the lack of an easily distributed and highly effective vaccine and limitations of current diagnostic and vaccine delivery technologies,” the plan says. “Remote vaccination by darting or bio-bullet has unknown yet potentially negative behavioral impacts on bison, and in turn, on visitor experiences such as watching wild animals.”

In a statement, Governor’s Office spokesperson Kaitlin Price called the plan “yet another insult to the state of Montana.”

“It is not based in science, fails to incorporate any comments from our agency professionals, and reflects a total disregard for the rule-making process,” Price said. “In the coming weeks, the governor will be submitting a formal response.”

The park in a release said the final environmental impact statement “solidifies the significant progress” made over the past 20+ years by the Interagency Bison Management Plan and its goal to maintain a free-range bison population in the park while also keeping Montana’s livestock brucellosis-free.

Two conservation groups, the Greater Yellowstone Coalition and the National Parks Conservation Association, said the plan and preferred alternative strike a healthy balance between many competing interests, including the Gianforte administration’s opposition.

“Bison management is complex, and this plan represents a continued commitment to coordinate with tribes, the state, and other interests to maintain a healthy population within the park and promote bison restoration on Tribal lands and hunting opportunities that honor treaty rights,” said Greater Yellowstone Coalition Executive Director Scott Christensen.