BISMARCK, N.D. (AP) — The beloved wild horses that roam freely in North Dakota’s Theodore Roosevelt National Park could be removed under a National Park Service proposal that worries advocates who say the horses are a cultural link to the past.

Visitors who drive the scenic park road can often see bands of horses, a symbol of the West and sight that delights tourists. Advocates want to see the horses continue to roam the Badlands, and disagree with park officials who have branded the horses as “livestock.”

The Park Service is revising its livestock plans and writing an environmental assessment to examine the impacts of taking no new action — or to remove the horses altogether.

Removal would entail capturing horses and giving some of them first to tribes, and later auctioning the animals or giving them to other entities. Another approach would include techniques to prevent future reproduction and would allow those horses to live out the rest of their lives in the park.

The horses have allies in government leaders and advocacy groups. One advocate says the horses’ popularity won’t stop park officials from removing them from the landscape of North Dakota’s top tourist attraction.

“At the end of the day, that’s our national park paid for by our tax dollars, and those are our horses. We have a right to say what happens in our park and to the animals that live there,” Chasing Horses Wild Horse Advocates President Chris Kman told The Associated Press.

Last year, Park Superintendent Angie Richman told The Bismarck Tribune that the park has no law or requirement for the horses to be in the park. Regardless of what decision is ultimately made, the park will have to reduce its roughly 200 horses to 35-60 animals under a 1978 environmental assessment’s population objective, she previously said.

Kman said she would like the park “to use science” to “properly manage the horses,” including a minimum of 150-200 reproductive horses for genetic viability. Impacts of the park’s use of a contraceptive on mares are unclear, she added.

Ousting the horse population “would have a detrimental impact on the park as an ecosystem,” Kman said. The horses are a historical fixture, while the park reintroduced bison and elk, she said.

A couple bands of wild horses were accidentally fenced into the park after it was established in 1947, said Castle McLaughlin, who in the 1980s researched the history and origins of the horses while working as a graduate student for the Park Service in North Dakota.

Park officials in the early years sought to eradicate the horses, shooting them on sight and hiring local cowboys to round them up and remove them, she said. The park even sold horses to a local zoo at one point to be food for large cats.

Around 1970, a new superintendent discovered Roosevelt had written about the presence of wild horses in the Badlands during his time there. Park officials decided to retain the horses as a historic demonstration herd to interpret the open-range ranching era. “However, the Park Service still wasn’t thrilled about them,” McLaughlin told the AP.

“Basically they’re like cultural artifacts almost because they reflect several generations of western North Dakota ranchers and Native people. They were part of those communities,” and might have ties to Hunkpapa Lakota leader Sitting Bull, she said.

In the 1880s, Theodore Roosevelt hunted and ranched as a young man in the Badlands of what is now western North Dakota. The Western tourist town of Medora is at the gates of the national park that bears his name.

Roosevelt looms large in North Dakota, where a presidential library in his honor is under construction near the park — a legislative push in 2019 that was championed by Republican Gov. Doug Burgum.

Burgum has offered for the state to collaborate with the Park Service to manage the horses. Earlier this year, North Dakota’s Republican-controlled Legislature passed a resolution in support of preserving the horses.

Republican U.S. Sen. John Hoeven of North Dakota has included legislation in the U.S. Interior Department’s appropriations bill that he told the AP “would direct them to keep horses in the park in line with what was there at the time that Teddy Roosevelt was out in Medora.”

“Most all of the input we’ve got is that people want to retain horses. We’ve been clear we think (the park) should retain horses,” Hoeven said. He’s pressing the park to keep more than 35-60 horses for genetics reasons.

The senator said he expects the environmental review to be completed soon, which will provide an opportunity for public comment. Richman told the AP the park plans to release the assessment this summer. A timeline for a final decision is unclear.

The environmental review will look at the impact of each of the three proposals in a variety of areas, Maureen McGee-Ballinger, the park’s deputy superintendent, told the AP.

There were thousands of responses during the previous public comment period on the park’s proposals — the vast majority of which opposed “complete livestock removal.”

Kman’s group has been active in gathering support for the horses, including drafting government resolutions and contacting congressional offices, tribal leaders, similar advocacy groups and “pretty much anyone that would listen to me,” she said.

McLaughlin said the park’s effort carries “a stronger possibility that they’ll succeed this time than has ever been the case in the past. I mean, they have never been this determined and publicly open about their intentions, but I’ve also never seen the state fight for the horses like they are now.”

The park’s North Unit, about 70 miles (112.65 kilometers) from Medora, has about nine longhorn cattle. The proposals would affect the longhorns, too, though the horses are the greater concern. Hoeven said his legislation doesn’t address the longhorns. The cattle are managed under a 1970 plan.

Theodore Roosevelt National Park “is one of very few national parks that does have horses, and that sets it apart,” North Dakota Commerce Tourism and Marketing Director Sara Otte Coleman said in January at a press conference with Burgum and lawmakers.

Wild horses also roam in Assateague Island National Seashore in Maryland and Virginia.

The horses’ economic impact on tourism is impossible to delineate, but their popularity is high among media, photographers, travel writers and social media influencers who tout them, Otte Coleman said.

“Removal of the horses really eliminates a feature that our park guests are accustomed to seeing,” she said.