hydromedusa in the Marianas Trench

Northern Mariana Islands

Pew Bertarelli Ocean Legacy

In January 2009, President George W. Bush established the Mariana Trench Marine National Monument, made up of three sections: the Islands, Volcanic, and Trench units. The monument is located in the federal waters and submerged lands around the Mariana Archipelago, about 1,400 miles south of Japan. The Mariana Trench, at 36,000 feet, is the deepest place on Earth—more than a mile deeper than Mount Everest is tall.

President Bush’s proclamation led to protections for waters that are home to rare beaked whales, dolphins, and colorful deep-water fish. More than two dozen species of seabirds inhabit the area, along with several species of threatened sea turtles; 29 species of marine mammals; and giant coconut crabs, the largest land-living arthropod.

Each of the units has unique features. The Islands unit includes about 42,000 square kilometers (16,400 square miles) of highly protected federal waters and the submerged lands around the islands of Uracus, Maug, and Asuncion. Together, the Trench and Volcanic units protect the seafloor, the Mariana Trench, and 21 undersea volcanoes. The Trench unit has been designated the Mariana Trench National Wildlife Refuge, while the Volcanic unit is now the Mariana Arc of Fire National Wildlife Refuge. Because of the trench’s depth and inaccessibility, most of the region’s wonders have yet to be discovered.

In the years since the declaration, the indigenous community identified several ways to improve the monument and called for transferring control of some submerged lands from the federal government to the government of the Northern Mariana Islands, a U.S. commonwealth.

The Pew Bertarelli Ocean Legacy project is continuing the efforts of its predecessor, Global Ocean Legacy, and is working with the communities of the Northern Marianas to improve management and enhance protections for the area.

Pew Bertarelli Ocean Legacy Project

The Pew Charitable Trusts and the Bertarelli Foundation joined forces in 2017 to create the Pew Bertarelli Ocean Legacy Project. This effort builds on a decade of work by both organizations to protect the ocean. Pew’s Global Ocean Legacy initiative, established in 2006, helped obtain commitments to safeguard more than 6.3 million square kilometers (2.4 million square miles) of ocean by working with philanthropic partners, indigenous groups, community leaders, government officials, and scientists. Since 2010, the Bertarelli Foundation has worked to create marine protected areas around the globe and simultaneously advance our understanding of marine science.

Our Work


Our Blue Planet–Protecting the Ocean

Quick View

Three-quarters of our planet is covered with water—and it’s this water that sustains life. But our liquid planet, home to half of the world’s known creatures and plants, is facing multiple threats, such as overfishing and commercial development. That’s why leading scientists say that 30 percent of our oceans should be protected. Host Dan LeDuc explores why this 30 percent data point is important with two people committed to safeguarding the oceans: native Hawaiian Sol Kaho’ohalahala, whose culture and livelihood depend on sustainable seas; and Matt Rand, who directs the Pew Bertarelli Ocean Legacy Project and has been working with people like Kaho’ohalahala since 2006 to keep our oceans healthy.