Interior Secretary Ryan Zinke spent the first day of his listening tour of the country’s national monuments visiting the famed Anasazi ruins in Utah’s Butler Wash and trying to assuage concerns of Utahns that undoing or shrinking the designation of the controversial 1.3-million acre Bears Ears National Monument would not automatically result in lots of oil rigs or mining equipment.

“The legacy and what I've seen should be preserved. The issue is whether the monument is the right vehicle," Zinke said, according to the Salt Lake Tribune. "What vehicle of public land is appropriate to preserve the cultural identity, to make sure the tribes have a voice and make sure you preserve the traditions of hunting and fishing and public access?"

Zinke -- a former Navy SEAL and congressman from Montana who calls himself a "Teddy Roosevelt Republican" -- was tasked last month by President Trump to review 27 national monuments across the country designated since 1996 that total 100,000 acres or more. In the executive order signed by Trump, the interior secretary also has been directed to produce an interim report in 45 days and issue a final report within 120 days.

Despite Zinke’s assurances on Monday, many Native Americans in the Southwest say that any change in Bears Ears’ status would be a major setback after years of lobbying to have the area named a national monument.

“The national monument has already been justified and there is no need for a review,” Cassandra Begay, a Navajo and the tribal liaison for the Native American advocacy group PANDOS, told Fox News. “Bears Ears is the first time that Native Americans played a crucial role in the creation of a national monument in the United States.”

The 1906 Antiquities Act authorizes the president to declare federal lands as monuments and restrict their use. After long-term discussions with Native American groups in the southwest, President Obama designated Bears Ears and Nevada’s Gold Butte as monuments in the waning days of his presidency.

The move was widely praised by environmentalists and Native Americans, but Republican lawmakers in Western states along with ranchers and those in the oil and gas industries widely panned the so-called “midnight monuments,” arguing that they do not represent the interests of the people in those states and will in time do more harm than good to the environment.

Trump has called the national monument protection efforts of his predecessors “a massive federal land grab,” saying Obama’s designations “unilaterally put millions of acres of land and water under strict federal control.”

Zinke faced criticism from Native American groups for traveling to Bears Ears for his four-day tour with an entourage of anti-monument politicians, including Utah Gov. Gary Herbert, and for only meeting with tribal leaders for a one-hour, closed-door meeting.

Davis Filfred of the Navajo Nation said that the meeting on Sunday in Salt Lake City wasn't enough time for the Bears Ears Inter-Tribal Coalition to make their points to Zinke. Filfred added that it seems Zinke is listening more to opponents of the monument than people who want it preserved.

Upon arriving at the Butler Wash trailhead on Monday, Zinke was greeted by PANDOS’ Begay and numerous other Bears Ears supporters. A video posted on YouTube shows Begay following Zinke and questioning him on why he won’t meet with tribal leaders before the interior secretary turns around, points his finger at her and chides her to “be nice.”

“My heart was racing when he came at me because I thought he was going to hit me,” Begay said. “It felt like he was about to snap! Certainly not what I expected from the interior secretary who is here on a listening tour.”

Others at the trailhead, however, had positive interactions with Zinke.

Hank Stevens, president of the Navajo Mountain Chapter, spoke to Zinke during his stop at Butler Wash and said Zinke promised to return to Utah to discuss the issue with tribal leaders.

“He reassured me that he is as worried about the issues as Native Americans are,” Stevens told Fox News. “This may be a fault of mine, but I always give people the benefit of the doubt.”

With the clock ticking on Zinke to hand in his recommendations to Trump, it is not entirely clear what powers the president actually has regarding Bears Ears.

Congressional leaders and courts have in the past contested many national monument designations – Franklin D. Roosevelt, for example, took heat for Jackson Hole National Monument, which later became Grand Teton National Park. Some monuments have also been scaled down, or enlarged, over the years by presidential orders or by Congress, but no president has ever attempted to eliminate his predecessor’s monument. If Trump tries to do so, the matter will most likely end up in court.

“It’s really unclear what powers the president has to abolish these monuments,” James Morton Turner, an associate professor of environmental studies at Wellesley College, told Fox News.

For his part, Stevens said the Trump administration could avoid all the legal tie-ups and protests if it just focused its attention somewhere a little farther away.

“President Trump seems to be all about space exploration,” Stevens said, noting the president signed a $19.5 billion spending bill for NASA. “I say they should go that way and leave us down here alone.”