William Snape, senior counsel for the Center for Biological Diversity, said that when Zinke finally reveals the lands he has targeted for reduction it will likely reflect the intent of those special interests.
"If this Administration proceeds to unlawfully strip monuments of their protections, I intend to help our neighbors in defending their national monuments, and protect the right of Washingtonians to visit these important pieces of our national heritage".
The review, Zinke says, is an attempt to give the public a voice in the designations, which require no public comment and no congressional approval.
Tourists come to enjoy our lands in many ways, including hiking, biking, horseback riding, hunting and bird watching. Changing the current protections poses a risk not only to the landscape and its inhabitants but also to our local communities.
For ranchers and people in the West who use public lands, the concept of an Antiquities Act designation just hits them the wrong way, Ethan Lane, executive director of the Public Land Council, told NewsHour.
That citation was also part of an April resolution calling for support of national monuments, including the four in Arizona that could have been affected by Trump's executive order: Grand Canyon-Parashant, Vermilion Cliffs, Sonoran Desert and Ironwood Forest. Zinke was in the area to discuss the review of Nevada's Gold Butte and the Basin and Range national monuments.
"I think it does indicate the fervor with which people love public, protected lands and recognize their value", says Spencer Phillips, an economist who co-authored the survey and the founder of the company.
Tribal groups, which backed President Obama's creation of Bears Ears National Monument, have also urged Zinke to preserve it as is.
Zinke has since offered a reprieve to six of those monuments, announcing he would recommend those lands remain protected.
"There's an expectation we need to look out 100 years from now to keep the public land experience alive in this country", Zinke said. "The Northeast Canyons and Seamounts Marine National Monument, off the coast of New England, contains some of the richest, most pristine marine habitat anywhere off the continental United States".
In July 2016, Rep. Rob Bishop, R-Utah, and former Rep. Jason Chaffetz, R-Utah, introduced the Utah Public Lands Initiative, which included a proposal for fossil fuel development in what is now Bears Ears.
When President Theodore Roosevelt signed the Antiquities Act into law in 1906, he established a legal framework for the protection of national treasures.
If the Trump administration prevails in undermining a previous president's legacy - even within the narrowest parameters of only changing boundaries - it makes any monument susceptible to tinkering.
Republicans had asked President Donald Trump to take the unusual step of reversing the designation, saying it will add another layer of unnecessary federal control and close the area to new energy development. "That narrative is patently false and shameful".
The news nonetheless represented a blow for conservationists and a win for conservative groups, Republican politicians and extractive industries across the USA west, which have led a concerted campaign against the Antiquities Act of 1906.
Central Coast Congressman Salud Carbajal said the announcement didn't provide any conclusion to the review process. Numerous legal scholars have reached the same conclusion.