Trump Sets Sights on Pacific Seafloor Near the Mariana Trench

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The Trump administration is expanding its deep-sea mining ambitions to the region around the Mariana Trench in the western Pacific, and is nearly doubling the proposed seabed mining area around American Samoa from 18 million acres to 33 million acres, an area bigger than Greece.

The move disregards unified opposition from Indigenous leaders in American Samoa, which imposed a moratorium on seabed mining last year. Gov. Pulaali’i Nikolao Pula has asked the Trump administration not to proceed without the territory’s consent, but the federal government plans to move forward with an environmental review. “Our fisheries are essential for food security, recreation and the perpetuation of our Samoan culture,” said Nathan Ilaoa, director of American Samoa’s Department of Marine & Wildlife Resources, last week in the Samoa News. Tuna makes up 99.5% of the territory’s exports.  

In a press release, Bureau of Ocean Energy Management (BOEM) acting Director Matt Giacona said the minerals could help U.S. manufacturing and defense. “These resources are key to ensuring the United States is not reliant on China and other nations for its critical minerals needs,” he said. In April, President Donald Trump issued an executive order to accelerate offshore mining despite international opposition and widespread concern from scientists about how little is known about the deep-sea ecosystem and the impacts mining could have on it. 

The announcement is the first time that the Trump administration has indicated interest in mining the waters around the Commonwealth of the Northern Mariana Islands, a U.S. territory made up of 14 islands in the Mariana archipelago. The southernmost island in the archipelago is Guam, a separate U.S. territory. It’s the latest of at least four areas in the Pacific that the Trump administration has sought to open to mining since April, including the waters surrounding the Cook Islands and the Clarion-Klipperton Zone, a mineral-rich area south of Hawaii. 

Nearly 100 square miles of the waters surrounding the Mariana archipelago are part of the Mariana Trench National Marine Monument. “These reefs and waters are among the most biologically diverse in the Western Pacific and include some of the greatest diversity of seamount and hydrothermal vent life yet discovered,” reads the description of the monument on the National Oceanic and Atmospheric Administration’s website. “It has many secrets to yield and many potentially valuable lessons that can benefit the rest of the world.”

The mining would take place west of the monument in an area spanning 35 million acres with its southernmost point between the islands of Rota and Guam, according to a notice published in the Federal Register on Wednesday that opened up the plan to public comment, known as a request for input, until Dec. 12. “The [request] does not constitute a decision to hold a lease sale but rather invites and encourages input from territorial and local governments, Indigenous communities, industry, ocean users, and the public,” the BOEM said. The commonwealth is home to about 44,000 residents, including Indigenous Chamorro and Carolinian peoples. 

The update from the BOEM this week comes just days after researchers from the University of Hawaii concluded that deep-sea mining could harm zooplankton, the tiny sea creatures that are an integral part of the ocean’s food web. The researchers found that a massive sediment plume created by a trial mining project in 2022 clouded the ocean for hundreds of kilometers. Zooplankton then fed on particles in the sediment that were found to be 10 to 100 times less nutritious than their typical food. “Because this is such a tightly linked, such a tight community food web, that will have these bottom-up impacts where zooplankton will starve and then the micronekton [that eat them] will starve and this community could collapse,” said Michael Dowd, lead author of the report. 

Dowd initially chose to study the waters at a depth of 1,250 feet because that’s where the Metals Co. planned to release its sediment. The company has since decided to do so at a lower depth, at 2,000 feet below sea level, in part due to data that found there’s fewer zooplankton there, and said that concerns about zooplankton at lower depths are overblown. Dowd said the absence of studies at that depth is not reassuring. “We really don’t know what that deeper community is like,” he said. 

In the Commonwealth of the Northern Mariana Islands, where plunging tourism has sparked a prolonged economic downturn this year, forcing hotel and business closures, the news of potential deep-sea mining was met with both concern and interest. “Success will depend on careful environmental management, respect for local and Indigenous interests, and transparent, science-based decision-making to ensure development aligns with both national and regional priorities,” Floyd Masga, the head of the local Bureau of Environmental and Coastal Quality, told Marianas Press.