SAN FRANCISCO (CBS SF) — Environmentalists and the outdoor recreation industry aren’t standing for President Donald Trump’s new executive order that threatens to rescind, shrink or resize dozens of recent national monument designations, including seven in California.

Trump’s new executive order requires Secretary of the Interior Ryan Zinke to review national monument designations that are over 100,000 acres and created under Presidents Barack Obama, Bill Clinton and George W. Bush.

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Trump argues that some national monument designations may “create barriers to achieving energy independence.”

But environmental groups and outdoor recreation companies see the review as the first step in an assault on public lands, with the ultimate goal being to open the land up for oil and gas drilling.

And they say they’re prepared to fight to keep these federal lands free from development.

San Francisco-based Earthjustice, a major nonprofit environmental law organization, says, “Any attempt to reverse or shrink a monument designation by the executive branch is unlawful under the Antiquities Act. Only Congress has the authority to modify a national monument. Earthjustice stands ready to defend the Antiquities Act and the national monuments protected under the law.”

According to Earthjustice, the seven national monuments in California that could be threatened are Giant Sequoia, Berryessa Snow Mountain, Carrizo Plain, Sand to Snow, San Gabriel Mountains, Santa Rosa & San Jacinto Mountains and Mojave Trails.

In Arizona, part of the Grand Canyon is also under review.

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The order draws special attention to the latest designation, the 1.3 million-acre Bear’s Ears National Monument in Utah. Republican Governor Gary Herbert and the Utah legislature has asked Trump to rescind the designation of Bears Ears as a national monument.

Ventura-based outdoor retailer Patagonia has not only been a staunch supporter of Bears Ears, but with Wednesday’s executive order, it has threatened to sue.

“We’re watching the Trump administration’s actions very closely and preparing to take every step necessary, including legal action, to defend our most treasured public landscapes from coast to coast,” Patagonia said in a statement.

Trump’s executive order calls for a preliminary report with suggested legislative acts on Bears Ears be provided to the president within 45 days after the executive order was issued. A final report on suggested actions on all national monuments under review is to be provided within four months.

Zinke tried to reassure the public as he discussed the executive order stating, “nobody loves public lands more than I do. You can love them the same. But not more.”

He argued that in some cases, the designation of the national monuments may have resulted in loss of jobs, but when pressed, he didn’t list any specific communities that lost jobs as a result of the monuments. He said that would be looked at in the review process.

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By Hannah Albarazi – Follow her on Twitter: @hannahalbarazi.