What should be done with feral horses at Theodore Roosevelt National Park?/Kurt Repanshek file

Editor's note: This recasts the first sentence to clarify that the National Park Service has not made a final decision on feral horses in Theodore Roosevelt National Park.

In weighing whether feral horses belong in Theodore Roosevelt National Park, the National Park Service is invoking Theodore Roosevelt's conservation legacy and the need to maintain a natural ecosystem.

While the Park Service hasn't firmly committed to removing the horses, as it is preparing a draft environmental assessment on the issue of both feral horses and cattle in the park located western North Dakota, simply broaching that potential outcome has generated an outpouring of support for keeping the horses from the public as well as from North Dakota Governor Doug Burgum.

"...wild horses were already established in the North Dakota Badlands when President Truman signed the bill creating Theodore Roosevelt National Memorial Park in 1947 and when it received official national park status in 1978," the governor wrote in a letter (attached below) to Theodore Roosevelt Superintendent Angie Richman. "For decades upon decades, these horses have coexisted peacefully with the national park and, in the process, have become a hugely popular attraction and an indelible symbol of the untamed character of the Badlands.

"...Removing these horses from the park, or reducing the herd size to a level that fails to support genetic diversity and longevity, would strike a blow not only to park visitation, but also to the economic vitality of Medora, nearby communities including Dickinson, and our entire state," he added.

Park officials late last year raised the question of how to deal with nearly 200 feral horses and nine cattle that roam the park. The park hasn't updated its horse management plan since 1978, and its cattle management plan dates to 1970. At issue is whether there should be any change in how the livestock are managed, whether the horses that roam the South Unit and the cattle in the North Unit should be removed as soon as possible, or whether the cattle should be removed and the horse herd reduced in number to a number of "fully contracepted horses" that would be allowed to live out their lives in the park.

"The park was established to pay tribute to the conservation legacy of Theodore Roosevelt, and that legacy is defined by a natural ecosystem, which includes the native animal species, such as bison, elk, pronghorn, and the native grassland ecology," Richman told the Traveler earlier this week during a phone call. "The park is embarking on this plan now so that we can address the non-native horses and cattle herds in the park so that we can better conserve those native aspects of the park."

The superintendent acknowledged that it's difficult to show definitively that the cattle and horses are having a negative impact on the park's grassland ecosystem. 

"But the more hoofed animals you have on the landscape, the more pressure that it puts on the landscape, and by addressing the non-native species it allows a little bit more resiliency for the native animals in the park," she said.

In addition, managing the horses and cattle -- which need supplemental feeding in the winter months, particularly this winter when 2 feet of snow is on the ground -- takes staff time and resources, said Richman.

"It's not just the flexibility for our native animals to be a little bit more resilient to things like wildfire, drought, climate change, but the management of horses and cattle has taken an increasing amount of our staff time and park resources as well, which compromises our ability to prioritize our natural ecosystem," she said.

Cattle can transmit a deadly disease to the park's bison herds/NPS file

Another issue is the chance that the cattle contract Mycoplasma bovis, a bacterial disease that can be deadly to bison.

"M. bovis has recently been found in some bison herds, like in Tallgrass Prairie (National Preserve in Kansas)," Richman said. "We currently do not have that here at the park, but we are actively monitoring for that. It is a real significant issue if it gets into the bison herd and can significantly reduce the number of animals that we have in the park. And so the biggest issue is something that's naturally present in cattle. And if the bison came nose to nose with the cattle, there could be a disease transfer."

Theodore Roosevelt National Park isn't the only unit of the National Park System with feral horses.  Assateague Islands National Seashore, Cape Lookout National Seashore, and Cape Hatteras National Seashore all have feral horse populations, while Death Valley National Park has feral burros that it has long tried to remove.

At Mesa Verde National Park in Colorado, staff from time to time deals with trespassing horses that enter the park. "The presence of trespass livestock is inconsistent with the park’s mission to preserve the cultural and natural resources within the park and has caused damage to springs, riparian areas and archeological sites and objects," the Mesa Verde website points out.

Cumberland Island National Seashore along the Georgia coast also has a feral horse population, and while the park staff views the horses as a non-native invasive species, it is not working to remove them even though they are known to have had a "significant impact" on the seashore's ecosystem.

"Studies of horse impacts at [Cumberland Island] have found that grazing activity, including vegetation consumption and trampling, significantly reduces vegetative cover, growth, and reproduction in these habitats," a 2018 assessment of the seashore's natural resources stated. "Grazing also appears to be altering plant species composition and is likely increasing the vulnerability of dunes and salt marshes to erosion and storm damage.

"In addition to impacts on vegetation, feral horses compact wetland soils, altering soil properties (e.g., infiltration rates) and disturbing vital soil-dwelling organisms," the assessment added. "The wastes produced by horses contribute to nutrient enrichment or eutrophication of wetlands and waterbodies, and can contaminate waters with pathogens, including E. coli bacteria. Together, these impacts make wetland habitats less favorable for native plants, fish, herpetofauna, and invertebrates."

National Park Service staff in Washington, D.C., did not immediately respond to an email asking why the agency doesn't have a system-wide policy for dealing with feral horses.

Back at Theodore Roosevelt, Superintendent Richman said that "allowing us to put our limited resources into the preservation of our native species, it's going to help us actually meet the enabling legislation of the park."

The public comment period on the question of how the park should deal with the horses and cattle has closed, and staff currently is analyzing the comments. The plan is to issue a draft environmental assessment later this spring and open it to public comment.