Supporters of Trump's decision have argued that when President Obama designated 1.35 million acres to Bears Ears, he overstepped his mandate. He strongly disputed a claim by the outdoor retailer Patagonia that Donald Trump "stole" public land by announcing the shrinking of two such areas in Utah, Bears Ears and Grand Staircase-Escalante.
Trump signed an executive order in April directing Zinke to review the protections, which Trump is able to upend under the 1906 Antiquities Act.
Sunset Arch rises from a sagebrush and slickrock flat in the Grand Staircase-Escalante National Monument in Utah. He said that "we have not drawn out the maps specifically, but it's a small percentage of Gold Butte". "We've fought to protect these places since we were founded and now we'll continue that fight in the courts".
A Zinke-led study into national monument declarations says that Trump should shrink OR and California's Cascade-Siskiyou and Nevada's Gold Butte national monuments by small amounts.
The California-based company, which is known for its activism, joins a growing number of organizations questioning the Trump administration's authority to slash the areas covered by Utah's Grand Staircase-Escalante National Monument and Bears Ears National Monument.
Protesters gather before a visit by President Trump in Salt Lake City. The Salt Lake Tribune via Associated Press Trent Nelson
Former President Barack Obama designated Bears Ears a year ago in an effort to protect land that several Native American tribes consider sacred.
This is the largest elimination of protected land in American history. While past presidents have used the Antiquities Act to protect unique lands and cultural sites in America, Trump is instead mangling the law, opening this national monument to coal mining instead of protecting its scientific, historic, and wild heritage. "As citizens we protected that land".
In a statement Monday, NARF said: "President Trump's action to revoke and replace the Bears Ears National Monument is not only an attack on the five sovereign nations with deep ties to the Bears Ears region, it is a complete violation of the separation of powers enshrined in our Constitution".
Outside Trump's announcement Monday, roughly 3,000 protesters lined up near the state Capitol. The administration and Republican leaders in Utah say taking the land out of the hands of the federal government will allow the state to decide what to do with it, including protecting some areas and possibly allowing development in others. The plans aim to shrink Grand Staircase-Escalante by nearly half, according to the documents. But it also gave presidents the authority to create national monuments on their own without Congress. The most recent instance came in 1963, when President John F. Kennedy slightly downsized Bandelier National Monument in New Mexico.