Photograph by Shawn Thew, EPA
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President Barack Obama signs designations for three new national monuments on July 10, 2015.

Photograph by Shawn Thew, EPA

Inside the Three Newest U.S. National Monuments

New monuments declared in California, Nevada, and Texas safeguard tracts of wilderness, from mountains to mammoth bones.

Oak woodlands, rugged mountains, and mammoth bones are among the newest protected natural treasures in the United States, as President Barack Obama is expected to designate three new national monuments Friday.

The president has created more than a dozen new monuments on land and sea during his term, using his authority under the 1906 Antiquities Act. The three new monuments combined total over one million acres, nearly doubling the public lands protected thus far by Obama. They join 117 existing national monuments, which have steadily been created by presidents over the past century. (Learn about controversies surrounding new monuments.)

Here are the newest national monuments:

Berryessa Snow Mountain, California

These Northern California oak woodlands lie about 100 miles (160 kilometers) from the Bay Area and have long been a popular recreation area for hikers, horseback riders, campers, anglers, and whitewater rafters. The 331,000 acre area in the Inner Coast Range is among the most biologically diverse parts of the state and is home to Tule elk, bald eagles, river otters, and rare dragonflies and butterflies. It is also home to a 5,000-year-old archaeological site that preserves history of Native Americans.

Basin and Range, Nevada

At 704,000 acres, this is the largest monument Obama has designated on land. About 110 miles (177 kilometers) north of Las Vegas, the site “represents some of the country’s last undisturbed mountain ranges and valleys in the southern portion of the Great Basin ecosystem,” according to the Wilderness Society.

The area provides key habitat to the sage-grouse, a large Western bird that has seen a rapid decline in recent years. It is also home to rare desert plants and Native American rock art.

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Volunteer Ralph Binson spent many hours excavating the impressive collection of mammoth bones in Waco, Texas, which has just been named a new national monument.

Waco Mammoth, Texas

This 107-acre site in Waco contains at least 24 mammoths, many of them youngsters that were being protected by their herd when the group perished during a catastrophic flood. The site was discovered in 1978.

"Waco Mammoth National Monument is the nation's first and only recorded evidence of a nursery herd of Columbian mammoths, and it also records the largest number of mammoths to have died in a single event in North America," says Raegan King, the site's manager.

A nursery herd is a group of females and their offspring.

“Our public lands are a birthright of all Americans and President Obama continues to build a strong conservation legacy through their expansion and protection,” National Wildlife Federation president Collin O’Mara said in a statement.

Correction: An earlier version of this story incorrectly stated that Waco Mammoth is the largest known concentration of mammoth fossils. The Mammoth Site at Hot Springs, South Dakota, has more mammoth fossils. Those are primarily adult males who died from different events.

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