Another Yellowstone Bison Slaughter

Yellowstone bison have been subject to evolutionary influences like harsh winters, predators, and other natural agents. Photo George Wuerthner

The state, federal and tribal groups involved in the Interagency Bison Management recently announced they would slaughter up to 900 Yellowstone bison this winter.

Yellowstone’s wild bison were declared our national mammal in 2016 and are of international significance.

Yellowstone bison are not the same as other bison scattered around the West. They are the most genetically pure bison left on the continent, largely influenced by natural evolutionary processes.

Nearly all bison herds, including those on tribal lands and other national park and wildlife refuges, have been domesticated and are treated more like cattle than wild animals.

Yellowstone bison migrate out of the park seeking lands where snow is less deep. Photo George Wuerthner

The annual massacre of Yellowstone bison is biologically degrading the herd. Yellowstone’s bison went through a genetic bottleneck in the last 1800s when approximately 50 animals were left in the park.

The annual killing of up to 20% of the herd to satisfy the overstated concerns of the livestock industry continues to erode this globally significant wild biological heritage. There are 100 million cattle in the US and only 5000 Yellowstone wild bison—which has greater importance to the world?

Yellowstone bison are being killed ostensibly to preclude transmission of brucellosis to domestic cattle, but the real reason is to prevent wild bison from occupying other public lands where they might compete with domestic animals for forage. Photo George Wuerthner

This carnage is based on a big lie—that bison threaten the Montana cattle industry.

The big lie is that bison “might” transmit brucellosis to cattle. It is true that brucellosis is a disease that can cause domestic cattle to abort. The reality is that the threat is greatly exaggerated.

First, the primary way that brucellosis might be transmitted is if a bison cow aborted their fetus and a domestic animal happens to lick the dead fetus or birth fluids. The occurrence of bison fetus abortions is infrequent.  Plus, it is not difficult to separate cattle from any area actively used by bison in the spring when bison might abort.

Even if a bison aborted its calf, coyotes, magpies, golden eagles and other scavengers quickly consume the fetus.

Second, most cattle can be vaccinated against brucellosis—though, like all vaccinations, they are not 100% effective. Additional vaccination could reduce the number of animals without protection.

All transmission of brucellosis to cattle have involved elk, but elk are not bottled up in the park or slaughtered to preclude migration from Yellowstone. Photo George Wuerthner

Third, though 20 ranch cattle herds have been infected with brucellosis, in all cases, the transmission was due to elk, not bison. Yet elk are not bottled up in Yellowstone or round-up for slaughter.

Fourth, as an indication that brucellosis is not the primary reason for the annual bison slaughter, bison bulls and calves can’t transmit the disease yet are regularly killed as part of the official butchery program.

Yellowstone bison are being killed ostensibly to preclude transmission of brucellosis to domestic cattle, but the real reason is to prevent wild bison from occupying other public lands where they might compete with domestic animals for forage.

The second part of the big lie is that too many bison are in the park. However, it is only “too many” because the Interagency Bison Management group agreed to keep the bison population below that arbitrary number.

Other studies by NPS biologists suggest Yellowstone could support almost as twice as many bison. Plus if bison were permitted to migrate and live on other federal lands surrounding the park, their numbers in the Greater Yellowstone Ecosystem could be significantly increased and any negative impacts to park vegetation could be reduced.

Wolves occasionally kill bison, and dead bison that die from other causes such as starvation are important to scavengers like coyotes, magpies, and even grizzly bears.  Photo George Wuerthner

Bison are also important to the other scavengers and predators in the park. When a grizzly finds a dead bison carcass in the spring it is like winning the “lottery.” Other predators like wolves occasionally succeed in killing a bison as well.  Reduction of the overall numbers by hundreds of animals means fewer bison dying from other natural causes like starvation and old age which in turn provides much-needed food for other park wildlife.

Bison are slaughtered either by Indian hunting outside of the park or capture and slaughter inside the park. The annual slaughter and removal of bison literally takes food out of the mouth of native predators and other wildlife. Overall this contributes to a degradation of Yellowstone’s bison genetic legacy and ecosystem. Photo George Wuerthner 

The Interagency Bison group tries to assuage the annual carnage with assurances that any slaughtered bison will be transferred to Indian tribes or be killed by tribal hunters.

Imagine if, for some reason, the last old-growth redwood trees (also of international significance) were being cut down. Would you feel any better about this destruction if the agencies justified it by saying they would cut the trees into planks to be distributed to tribes to make huts or redwood decks?

The Missouri River Breaks National Monument and adjacent Charles M. Wildlife Refuge is a perfect location for transplants of Yellowstone’s bison. Photo George Wuerthner

There are numerous places on public lands surrounding Yellowstone where wild bison could roam. They should be encouraged to use these lands rather than destroy them. The transfer of Yellowstone bison to other public lands like Montana’s Charles M. Russell National Wildlife Refuge or to Forest Service lands in the Upper Green River area of Wyoming is also an option.

Yellowstone’s bison are of global significance and part of the planetary wild heritage. Photo George Wuerthner

Currently, about 75,000 acres outside of the park are available for bison, however, due to tribal hunting and harassment from agency officials, bison seldom occupy these lands. Another potential solution is to expand Yellowstone’s borders to the north of Yankee Jim Canyon and to the northwest into the Gallatin Range providing far more protected wildlife habitat for bison to roam.

What disturbs me is how little outrage is expressed about this annual slaughter. Most of the big Green groups seldom mention the butchery nor publish all the reasons this carnage is unnecessary. The killing of wild bison has become normalized. It should never be permitted to become “normal.”

Yellowstone wild bison are part of the global biological heritage. We must start to treat them as the matchless legacy they represent.

Bio: George Wuerthner is an ecologist who has published three books on Yellowstone as well as others on wildlands protection, including Protecting the Wild: Parks and Wilderness the Foundation for Conservation.


  1. Maggie Frazier Avatar
    Maggie Frazier

    Yup – that time of year once again. This press release is from the Buffalo Field Campaign:

    Press Release Yellowstone National Park Plans to Continue Decades Long Slaughter of Ecologically Unique Yellowstone Bison – Buffalo Field Campaign ( – 2021-12-10 0801.emlhe

    1. Ed Loosli Avatar
      Ed Loosli

      Maggie:: Too bad the Buffalo Field Campaign which loudly calls for the right to let Yellowstone buffalo to ROAM FREE, also supports the Native Americans to be in on the slaughter of the buffalo when they literally take a step outside the protection of the Park boundary.

      The tribes participating in the buffalo slaughter are being used by the Government and the livestock industry to do their dirty work for them, and the Yellowstone buffalo will never ROAM FREE as long as they are slaughtered when they follow their instincts to migrate in and out of the Park.

      1. Ida Lupine Avatar
        Ida Lupine

        Over the last few years, there have been many suggested programs about letting the bison migrate, or brought to tribal lands, and it seems to have stalled?

        Whatever happened to that? There’s got to be something better than killing nearly a thousand of them per year. It really is no better than the 1800s or turn of the 20th century era. It’s just so awful and shameful.

      2. Maggie Frazier Avatar
        Maggie Frazier

        Maybe “better the tribes doing the hunting rather than outside hunters”?
        Read one piece that said there would be a line of “hunters” waiting for the buffalo to step out of their safe place. Thats not hunting – its a kill zone!
        As Ida said – whats happening (or not) with the supposed “programs” that would allow the tribes to have their own herds?

        1. Ed Loosli Avatar
          Ed Loosli

          Maggie:: This line of “hunters” are in fact often the tribal hunters themselves waiting for the Yellowstone buffalo to step out of their safe place. You are right, that is not hunting – its a kill zone. Many tribes do have their own herds, but their buffalo lands are fenced and they are not the un-fenced wild herds of Yellowstone N.P.

          1. Maggie Frazier Avatar
            Maggie Frazier

            As always, Ed, its the animals that are on the bottom every time. No matter in which “arena”.

  2. rastadoggie Avatar

    This injustice – plus our treatment of wolves – keeps me up at night and informs my misanthropic world view. Thanks for ideas on solutions.

    1. Ida Lupine Avatar
      Ida Lupine

      I know, I hate it too.

      I don’t understand why it keeps going on. So many are being killed.

  3. Beeline Avatar

    That is how this country solves its problems. It kills. It was founded largely on killing in the first place and continues to do so. Witness the kill list of wildlife services.

    Last year they killed 2,537 cliff swallows, 3,560 killdeer plovers, 26,173 mourning doves, 25,400 beavers and 15,102 black-tailed prairie dogs to mention a few species out of a total of 1,508,896 animals they sent to the spirit world. Nothing is safe. Killing = $.

    The paradigm of killing has soaked into the minds of the populace. Almost everyday somebody shoots some body else. The government sets a very bad example by dropping 500 pounders on its “enemies” so it follows that some of the people will kill their ‘enemies’ as well. And then the government spends its “hard earned” billions on new weapons systems- for more killing.

    Out of balance is a polite way of stating what is going on. More killing than life enhancing activity can only end in great suffering.

    The earth will have its day of cleansing, and it is not that far off.

    Wakan Tanka nici un

    1. Ida Lupine Avatar
      Ida Lupine

      Yes. It’s shameful.

      Is there still really any truth to the constant claims of brucellosis that are supposed to justify it?

      1. Maggie Frazier Avatar
        Maggie Frazier

        there hasnt ever been transmission between bison & livestock! However, it does happen between elk (who are not quarantined & slaughtered) & cattle. Its just wrong.

      1. Maggie Frazier Avatar
        Maggie Frazier

        Interesting that: Alternatives the agency DOESNT consider include temporarily curtailing livestock grazing activities in areas where the bureau has determined conflicts between livestock and wildlife often recur at the same time of year when newly born lambs and calves graze on U.S. times and native carnivores are rearing their offspring.
        In other words – using common sense????

  4. Michael Kellett Avatar

    We need to expand Yellowstone National Park. Most of the lands around the park are public lands open to livestock grazing, trophy hunting, oil and gas drilling, roadbuilding and other destructive activities. This threatens not only bison but also wolves, grizzlies, mountain lions, pronghorns, and other wide-ranging species.

    Quadrupling the size of Yellowstone to 8 million acres would protect these wildlife species. We already own most of these lands. We could acquire key ranch lands adjacent to the park.

    Ranchers, trophy hunters, the forest industry, and other resource exploiters would not like it, but I am sure most Americans would welcome such a park expansion.

    1. Ed Loosli Avatar
      Ed Loosli

      Hear Hear!! Michael Kellert… Yes indeed, Yellowstone N.P. is surrounded by our Public Lands (mostly US Forest Service and some BLM lands) that are every bit as important to the overall health of the Greater Yellowstone Ecosystem as the Park itself.

      This would be a perfect time to enlarge Yellowston National Park to 8,9 or better yet 10 MILLION acres. This would allow a protected connection between Yellowstone N.P. and Grand Teton N.P. as well as all the national forest and BLM lands surrounding these current national parks.

      Does anyone here on “The Wildlife News” of any such bill being proposed to do this, or maybe a movement to get Pres. Biden to declare a huge 8 Million acre NATIONAL MONUMENT surrounding Yellowstone N.P. and Grand Teton N.P.??

    2. Ida Lupine Avatar
      Ida Lupine

      I wish, for connectivity to the grizzlies and other wildlife, and many other reasons!

    3. Reclaimthewild Avatar

      Some good news regarding land acquisition to enhance connectivity and habitat in this area

      1. Ida Lupine Avatar
        Ida Lupine

        Oh that is good news!

  5. Nuri B Pierce Avatar
    Nuri B Pierce

    Can something be done to prevent, once again this injustice and ecological crime?

  6. Barrie Gilbert Avatar

    Do the recent ¬¬bison slaughters rob grizzlies of food that leads to grizzly turning to livestock and hunter kills outside their protected area? This contributes to unsustainable losses to the grizzly population. This argument requires an understanding of park service management mandates, their current management policies for wildlife in natural ecosystems and the landscape ecology of bison and elk migration in an incompletely protected ecosystem. No apologies. This is the state of current ecological and human social systems.
    In the simplest of terms, the migratory animals of YNP are born, grow and reproduce in large, high elevation habitats, where short summer afford protection in the warmer months (excepting vehicle mortality) but they complete their annual cycle by migrating in winter to lower elevation habitats. This ancient adaptation now exposes then to widespread legal and illegal killing. To an ecologist this represents a failed model of ecosystem management: a set of national park policies that accepts that animals that grow and reproduce in a national park in summer can be hunted or culled (bison) in fall and winter. This policy robs park carnivores and scavengers of a high-quality food. In the case of bison carcasses, dozens annually, would provide. What grows in a national park should stay in that park. The cavalier attitude of the park service regarding bison culling is little different than treating the park as a game farm for exploitation outside the park.

    This objection may seem radical to the tribal shooters who benefit from slaughtering emigrating Yellowstone bison near Gardiner, Montana on the park boundary. Hunting dozens of herds coming on to public land for legal hunting. But the consequences can be significant for carnivores and scavengers (bears, wolves, coyotes, ravens) that are being robbed of a rich source of foods. These nutrients are critical for biological production of the park. It is easy to say that this is a consequence of the park not being large enough to include wildlife migration corridors and winter range. The solution to protecting an intact, public trust National Park ecosystem is not to kill animals behaving naturally, but to acquire land where necessary to include as protected lands in the present day conflict zone. In fact, the situation exposes a major anomaly, and a long-standing problem, for the National Park Service.
    The Service is guided by legal management mandates to maintain ecological and evolutionary processes that, on paper, are admirable and scientifically and socially defensible. But their actions fail to meet their legal obligation. How so?

    1. Maggie Frazier Avatar
      Maggie Frazier

      Makes sense to me – I agree!

    2. Ida Lupine Avatar
      Ida Lupine

      They seem to be going after Yellowstone’s wolves too. 15 killed already at the north of the Park. Why is it being allowed?:

  7. Maggie Frazier Avatar
    Maggie Frazier

    Another organization that agrees with Mr.Wuerthner regarding the current fire fighting “programs”!

  8. Rich Avatar

    On another wildlife travesty, this is the only article I was able to find on the rally held December 4 in San Francisco to protest the National Park Service decision to continue subsidized cattle ranching and the killing of tule elk at Point Reyes National Seashore. Does anybody know how many people actually participated?

    “Sportscaster and former NBA scout Bonnie-Jill Laflin joined the rally in person and passionately addressed the crowd: “As a little girl, I was fascinated with them [Tule elk] and their beauty… I was heartbroken to see… they’re dying miserable deaths… Now the NPS supports a plan to shoot some of the Tule elk at the request of the ranchers, and I was outraged because if animals can’t be saved at a National Park, where can they be saved? The Tule elk are rare animals who deserve protection and not a bullet from the cattle ranchers.”

    1. Maggie Frazier Avatar
      Maggie Frazier

      Heres another article – dont think that gives a number of participants either. Western Watershed & Turtle Island Restoration Network are 2 other organizations that have been following this mess!

  9. Restorethewild Avatar

    Find a way to buy the land or buy the leases. This is how we end the slaughter.

George Wuerthner is an ecologist and writer who has published 38 books on various topics related to environmental and natural history. He has visited over 400 designated wilderness areas and over 200 national park units.

Subscribe to get new posts right in your Inbox