After weeks of damaging midnight environmental rulings that have removed crucial endangered species protections, restrictions on mining the Grand Canyon, and allowed leasing of public lands for oil development, President Bush protected a whopping 195,000 square miles of the central Pacific’s tropical blue heart. With the stroke of a pen, he created the Mariana, Rose Atoll and Pacific Remote Islands Marine National Monuments—and set aside an area the size of his home state of Texas, the largest swath of protected ocean on the planet.

This area was relatively easy to protect. Being thousands of miles out to sea, the central Pacific holds little commercial value. But it was not just a symbolic move. This is truly a singular place, almost untouched by humans. These pristine reefs, atolls and islands teem with a spectacular array of life. It is one of few remaining places where top predators like sharks and tuna still swim in abundance, home to endangered sea turtles, hundreds of fish species, porpoises, humpback and pilot whales. 300 species of stony corals. Giant clams. Literally millions of seabirds and migratory shorebirds. This place is a living laboratory offering a peek into what reef communities looked like hundreds of years ago.

The Mariana monument cradles the famous Mariana Trench, a geologic wonder nearly seven miles deep and five times as long as the soon-to-be-mined Grand Canyon. It also encompasses an acidic undersea that boils with submerged active volcanoes and thermal vents that house otherworldly, little-studied deep-sea species.

And Bush didn’t wimp out on protection: he granted these monuments the highest conservation level, prohibiting commercial fishing, mining and drilling. The practical challenge will be monitoring such a mammoth area in such a remote place. Big-ticket species like tuna and sharks could be targets for illegal fishing operations.

This is a huge and important initiative, but it covers far less than the over 700,000 square miles (a little more than three Texases) that were under consideration. The monuments extend 50 miles offshore, a big improvement on the measly 3-mile safeguards previously in place for some island national wildlife refuges—but substantially less than the 200-mile radius recommended by environmental organizations to accommodate wide-ranging species like sharks, seabirds, and turtles.

The need to conserve vanishing wild places and creatures on land has been long understood. Yellowstone, the world’s first national park, was established in 1873. These new monuments, in tandem with Bush’s creation of Hawaii’s Papahanaumokuakea Marine National Monument in 2006, show a sea-change in attitude towards ocean conservation. It’s taken over a century for us to recognize that the ocean is not an infinite resource—and that there are unique and biologically important sea environments that need protection.

We also need to create ocean sanctuaries closer to home. Proposed marine monuments in the Gulf of Mexico were shot down by powerful industrial fishing interests. We still overfish U.S. waters. “Factory” fishing practices like bottom trawling empties the sea of life—much of which is thrown away dead, as useless “bycatch”—while utterly destroying habitat. And, says Joshua Reichert, managing director of the Pew Environment Group, “the high seas are like the Wild West, exploited by all and protected by no one.”

Let’s hope that these monuments usher in a whole new era of ocean conservation both in the US and around the world.

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