Yellowstone National Park Bison ManagementYellowstone National Park is the nation’s first park and admired by people around the globe. Folks often acquaint the Park with two iconic figures – Old Faithful geyser and the wild bison. These bison are the remaining few wild herds of their kind in the nation. During a majority of the year, these bison graze pastures within the Park for its 4+ million annual visitors to admire, or to take Bison selfies. However, each winter, these bison migrate to lower elevations for better cold season grazing, often out of the Park onto lands in Montana.

The Park is required to manage bison populations (according to the IBMP, discussed later) at a reasonable number according to the carrying capacity of forages within the Park boundaries. This has not occurred. Now, bison population numbers are well above agreed upon numbers, resulting in damage and degradation of forage and rangeland health within the Park. This ends up in the animals’ migration out of the Park each winter in search of more food. This is where a complex, at times controversial, management program comes into play.

Each winter, stories of the annual bison cull hit the media waves. Bison that leave the Park are sometimes gathered at Stephens Creek in order to harvest their meat used for consumption. Others are allowed to be hunted by Native Americans. Activists are not happy with this bison cull and will often protest near the bison capture facilities in an attempt to stop the bison slaughter. These activists will go to great lengths for attention, some even chaining themselves to concrete barrels near the bison working pens to stop the corralling of animals.

Doing nothing to manage the bison is not in the best interest of the wild bison herds or sustainability of the YNP ecosystems. Conservation of the species is an important and needed tool, but it must be in balance with other wildlife species, ecosystems, natural environments and society. So, after much work and collaboration, management plans have been created.

The management of Yellowstone Bison is under the direction of a multi-agency effort called the Interagency Bison Management Plan (IBMP). The organizations involved in administering the IBMP include the National Park Service, USDA-Forest Service, USDA-Animal & Plant Health Inspection Service, Montana Department of Livestock and Montana Fish Wildlife & Parks. Click here to read more about IBMP.

As the IBMP was adapted in 2000, its objectives are to:

  • Maintain a wild, free-ranging bison population;
  • Reduce the risk of brucellosis transmission from bison to cattle;
  • Manage bison that leave Yellowstone National Park and enter the State of Montana;
  • Maintain Montana’s brucellosis-free status for domestic livestock.

Read more about the Montana bison and brucellosis management plans from the Department of Livestock and the Fish, Wildlife and Parks.

This is a very complex program that I will admit to not understanding fully. People study the complexity of the subject for years. However, for the past three years, I worked in a policy organization involved in work on the subject and have worked with several ranchers directly impacted by the Yellowstone bison and the impacts those animals have on ranchers’ ability to make a living in Montana. I will share a few of my observations on the bison situation in Montana.

People concerned about the well-being of bison herds in Yellowstone National Park want these wildlife free to roam as they please. Most Americans, including admirers abroad, have nostalgic perceptions of bison roaming the vast open plains prior to settlement by white Americans.

Today, our country (and world) are much more heavily populated and the environments have changed as we’ve utilized our resources to produce foods for human consumption and co-habiting wildlife species. We cannot rewind centuries, nor is it realistic to remove people from the land, and consequently important farms that provide food for global markets, to provide roaming grounds for a wildlife species. Everyone wants the bison to roam, but not many seem willing to foot the bill or have the wildlife in their backyards.

Ranchers often come across as the bad guys in the eyes of those not familiar with the entire situation. Ranchers are perceived as greedy and raping the earth from its wildlife habitat for wanting to raise cattle and prevent interactions from the wild, disease-carrying bison. Ranchers have as much right to live and ranch as good stewards of their lands as someone who has the right to live in a New York apartment building or on the California coast.

Bison are a concern to ranchers for a number of reasons. This includes damage to property, inability to control the ranging animals, damage to vital forage stands or rangelands and danger to livestock or humans. The most controversial and discussed threat is the spread of a disease called Brucellosis.

Brucellosis (Brucella abortus) is a zoonotic infectious disease. Zoonotic meaning that it can be transmitted from animals to humans. According to the CDC brucellosis page, People can get the disease when they are in contact with infected animals or animal products contaminated with the bacteria. Animals that are most commonly infected include sheep, cattle, goats, pigs, and dogs, among others. More about the disease and its threat to humans and animals can be learned from the World Health Organization.

Brucellosis organisms live in the reproductive tract of infected animals causing abortion and sterility. This can have a significant economic impact in livestock herds and a negative impact on health of wildlife species. The organisms are spread in a number of bodily tissues or fluids, specifically noted in the fetal or placental tissues.

Once common in this country, brucellosis has been eliminated in all domestic livestock herds and most wildlife. Proper vaccination with testing and culling procedures can be used to manage the disease and aid in prevention and elimination. The last remaining reservoir of brucellosis in the U.S. was the bison herds in Yellowstone National Park. The Park hasn’t been overly cooperative to implement management procedures to eliminate the disease in bison herds. In turn, the disease has now spread to wild elk herds which have a greater travel radius.

Brucellosis can have a significant impact on cattle herds, agriculture being the largest industry in Montana. Cattle that contract brucellosis often abort, have lower milk production or may become sterile. Risk of spreading the disease among cattle resulted in the Brucellosis Eradication Program. Once a state is free of the disease, it gains Brucellosis Free Status. If a state does not have a Brucellosis Class Free Status, other states may require cattle go through extensive testing before relocation. This testing is expensive and time-consuming.

While still having a presence of brucellosis, due to transmission from wildlife, Montana is able to maintain a Brucellosis Class Free Status for a majority of ranchers and cattle herds, by implementing a Designated Surveillance Area (DSA) in southwestern Montana, an area including the Greater Yellowstone Area. Ranchers in the DSA undergo more stringent testing requirements so that others in the state are not threatened by the disease or its economic and biological impacts.

Activists argue that a transmission of brucellosis from bison to cattle has not been documented. However, disease transmission in uncontrolled environments is biologically possible. This paper from APHIS gives a history of the conflict and research by Texas A&M that shows transmission can occur.

In 1990, researchers at Texas A&M demonstrated that bison infected with Brucella abortus could spread the disease to cattle through contact. Although this was proven under controlled conditions, it is difficult to document transmission of a disease in the wild. In order to document this, a researcher would need to be present when the transmission occurred and collect samples for tissue culturing. In addition, the animals would have to have been previously tested before the transmission had occurred to verify that the event was caused by the bacterial transmission at the observed time. Therefore, it was necessary to conduct this research under controlled conditions. Even though transmission in the wild is difficult to document, results of epidemiological investigations point to domestic bison as the likely source of the disease in infected cattle herds found in Wyoming and North Dakota. In addition, wild elk or bison in the GYA have been identified as the most probable source of infection for five additional cattle herds. Infected elk were the most probable source of brucellosis infection (fistulous withers) in horses in Wyoming. Most recently, elk were the source of infection of a cattle herd in Idaho.

Ranchers utilize a number of management practices to prevent interactions between domestic cattle and wildlife at critical times for potential brucellosis transmission. This also includes vaccinations, testing for the disease and cooperating with state and federal agencies to not graze pastures in elk calving grounds until the threat has decreased.

Pressure from activists and those will little to no knowledge or investment in what happens on the ground have restricted ability of state and federal agencies to act with more force in managing wildlife and the disease. This results in a continual eroding of grazing availability for ranchers and expansion of the above mentioned DSA.

Ranchers, in general, are pushing for greater investment for development of a vaccine for bison, for the Park to put more effort into eradicating the disease and to maintain agreed-upon population standards that reflect sustainable carrying capacity of the YNP ecosystems. Relocation of the bison to other public or private locations is a possibility, however, there are significant concerns about disease eradication, funds to provide infrastructure to keep bison in their designated areas and enforcement to prevent damages to neighboring livestock, rangelands, property and people.

As I stated above, this is a very complex, controversial and heated issue stemming from my brief experience with the topic. There will be other opinions and perspectives on the issue. These 1,750 words are only a brief explanation of the topic and I encourage you to click reference links throughout this article to learn more about the subject.

Bottom line: Yellowstone bison are a national treasure. They are threatening wildlife that can endanger ecosystems and a significant portion of the region’s economy. Conservation of the species is a viable solution, however cooperation is an important matter to ensure funding, biosecurity and stability remain in tact. Elk will be an important part of the management plan to reduce and eliminate the presence of brucellosis. Unfortunately, nostalgic perspectives seem to be a big obstacle for many admirers to overcome so we can work toward sustainable solutions for everyone. Until then, the discussion of brucellosis and annual bison population reductions will continue. State and Federal agencies continue to work on improving the IBMP and discussions are ongoing on Economic Impact Statements and revisions of the management plans.