Mona Mangloña grew up on the southernmost of the Northern Mariana Islands. Rota is known for its unspoiled scenery and warm-hearted residents. She says living in this small but sacred Pacific island fosters a deep connection to the land, the water and everything in between.
For the 29-year-old social worker and environmental advocate, the ocean is not something distant or abstract. It is “quite literally your back and front yard growing up.” Mangloña says the Pacific is woven into the daily lives of Rota’s Indigenous Chamorro (also known as CHamoru) communities. It nourishes them with its bounty and brings healing.
Now, Mangloña worries the ocean and the life it sustains face a new threat.
The Commonwealth of the Northern Mariana Islands is a United States Pacific territory. As such, the US federal government can permit seabed mining east of the Mariana Trench National Marine Monument and west of the Northern Mariana Islands. The US began that process last November.
These efforts are part of President Donald Trump’s push to secure from the seabed critical minerals such as nickel, cobalt, copper and manganese. “Our nation must take immediate action to accelerate the responsible development of seabed mineral resources, quantify the nation’s endowment of seabed minerals, reinvigorate American leadership in associated extraction and processing technologies, and ensure secure supply chains for our defence, infrastructure, and energy sectors,” Trump wrote in an executive order last April.
The southern boundary of the area in question lies roughly halfway between Rota and its neighbouring island, Guam. Further south in the Pacific, a similar process was initiated a few months earlier in American Samoa. All are US Pacific territories.
The Northern Marianas, Guam and American Samoa share concerns that deep-sea mining could irreversibly damage their marine ecosystems, which are some of the world’s most biodiverse. Such fears are shared by several scientists and conservation groups.
Pacific island residents also fear the disruption of their cultural practices and food systems. For some, the proposal feels like a familiar pattern: bearing risks in the name of strategic interests, without meaningful consent.
Pacific communities are already bearing the costs of decisions made thousands of miles away in Washington, DC – from nuclear testing in the Marshall Islands to the environmental damage of militarising Guam and the Northern Marianas.
As US territories, American Samoa, Guam and the Northern Marianas have little control over federal policies. They have delegates in Congress but their representatives cannot vote; residents are American citizens but they cannot vote in presidential elections.
“Time and time again we’ve been reminded that decisions are already being made about us, without us,” Mangloña says. “It’s a never-ending pattern of colonial oppression and extraction. How much more do we have to give? How much more can be extracted from our homes?”
Scouring the seabed
Mining vast tracts of ocean floors rich in potato-sized nodules containing minerals is a priority for the current US government. Trump’s April executive order says he is seeking to establish the US as a “global leader in responsible seabed mineral exploration”. The order explicitly seeks to counter China’s dominance in supplying the elements vital for batteries and other modern technologies.
The order tasked the National Oceanic and Atmospheric Administration (Noaa) and the Bureau of Ocean Energy Management (Boem) with fast-tracking the necessary reviews, licences and commercial permits for this mining, in both US and international waters. This sidesteps an existing, UN-led, multilateral process.
Since the order, the government has announced plans to lease areas offshore of the US states of Virginia and Alaska for mining. It is considering an application from The Metals Company, based in Canada, to mine in international waters.
In October, Boem identified roughly 33 million acres (13 million hectares) of seabed off American Samoa as an area for potential exploration and mining. This came six months after Impossible Metals, a company based in the US state of California, submitted an unsolicited request to mine about half of the area. The company says its autonomous underwater robot can identify and avoid harvesting nodules that have visible marine life, to help minimise habitat disturbance.
The area borders the National Marine Sanctuary of American Samoa, which encompasses the Rose Atoll Marine National Monument. This is one of the world’s most pristine atolls. In January, Noaa announced a survey to map the sea floor off the territory, for mineral deposits. Meanwhile, in the Northern Mariana Islands, roughly 69 million acres (28 million hectares) of seabed are being eyed for potential leasing to mining companies.
Scientists say the proposed mining areas in both American Samoa and the Marianas (including Guam) overlap extensively with seamounts. Key ocean ecosystems, these underwater mountains host a huge array of marine life. It tends to exceed the biomass and biodiversity of the flat seafloor, known as the abyssal plain, that surrounds them.
Cherisse Du Preez, a deep sea ecologist at the University of Victoria in Canada, says mining along seamount slopes carries greater environmental risks than mining abyssal plains. Currents can spread disturbed sediment and pollution far from mining sites across the surrounding bottom area of the sea called the benthic zone, she says. They push water upward at seamounts, for example, and create swirling eddies. Mining contaminants could enter the food chain and accumulate in the larger fish that people eat. The mining activity could also disrupt migrations, threatening fisheries and triggering economic crises in communities.
In a statement to Dialogue Earth, Boem says it “takes the unique ecological characteristics of biological habitats including seamounts seriously”.
“It is important to note that Boem will not authorise activities unless a full environmental review demonstrates that impacts, including sediment plumes, benthic disturbance and noise or light emissions, can be understood, minimised and appropriately managed.”
Oliver Gunasekara, the CEO of Impossible Metals, says the technology his company is developing minimises disturbance by hovering above the seafloor and picking up nodules for collection rather than dredging the seabed. “The goal is to minimise disturbance and avoid the sediment plumes that have raised legitimate environmental concerns in the past,” he says.
Gunasekara also stresses that he understands why people are concerned and proposals should be scrutinised carefully.
“We have deep respect for the people of American Samoa and their relationship with the ocean. The ocean is central to culture, identity and daily life in the islands, and that deserves recognition and care,” he told Dialogue Earth.
Following the money
In American Samoa, whose primary economic driver is tuna fishing, the mining proposals are causing residents to worry about the impacts to their traditions. For example, palolo worms are a culturally significant delicacy that swarm seasonally while the akule, a mackerel-sized fish, is commonly fished.
“The ocean, to us, is not a resource. It is an entity that has always provided for us,” says Sabrina Suluai-Mahuka, an educator and environmentalist who used to lead the territory’s climate resilience office.
Impossible Metals has pledged to the islands 1% of profits generated from selling any minerals extracted from American Samoa’s exclusive economic zone. Suluai-Mahuka calls this “an insult” that merely adds to local frustration: “To industry players and to federal agencies, deep-sea mining is seen as a lottery ticket. But for us, it’s a gamble on our livelihoods that we can’t afford.”
In response, Gunasekara says: “The revenue-sharing idea that was discussed is voluntary and is meant as an initial step to acknowledge that local communities should participate in the economic benefits of any activity in nearby waters.”
The economic situation on these islands is difficult. Politicians in the Northern Marianas say there is an escalating economic crisis, making new sources of income difficult to ignore.
The potential for marine and ecological harm and degradation from deep-sea mining is likelyDavid Apatang, governor of the Northern Marianas
American Samoa has a moratorium on deep-sea mining that remains in effect. Leaders including the territory’s most senior elected figure, Governor Pulaali’i Nikolao Pula, have expressed opposition. But Pula has also previously said seabed mining could be “an opportunity that should not be missed” – if it is pursued responsibly, with transparency and with the interests of American Samoan residents in mind.
Meanwhile Guam’s governor, Lou Leon Guerrero, has urged the federal government to refrain from advancing leasing or exploration activities in the Marianas. She said in a public comment on the proposals that deep-sea mining poses “irreversible harm, substantial scientific uncertainty, minimal economic upside, and no demonstrated national security benefit.”
The Northern Marianas’ governor, David Apatang, said in a letter to Boem he could “neither fully support nor fully oppose” offshore mining activities in his territory’s waters. He blamed the information provided, calling it insufficient for anyone to fully understand the potential effects of seabed mining.
“My administration has expressed with a loud and clear voice that the potential for marine and ecological harm and degradation from deep-sea mining is likely, and that when science has made that argument convincingly probable, that no action must be taken,” Apatang tells Dialogue Earth.
Mangloña fears troubled economies could pressurise residents into capitulation: “One of my major concerns is this false narrative that deep-sea mining is going to save our community.”
Gaps in science, and engagement
Scientists at the National Academies of the United States are currently tasked with fixing this information gap, and establishing baseline data in areas targeted for mining. Their study will assess the feasibility and economic viability of extracting minerals from the ocean floor. It will also consider the social, cultural and economic impacts of seabed mining, and potential ways to reduce harm.
Boem, Noaa and the Bureau of Safety and Environmental Enforcement are sponsoring the study. But a professor on the panel conducting the work, Steven Mana‘oakamai Johnson of Cornell University in New York, tells Dialogue Earth the researchers will operate independently. Johnson was born and raised in Saipan, the capital of the Northern Mariana Islands.
Residents of US Pacific territories have criticised the lack of meaningful consultation on deep-sea mining in their waters. A consultation with government officials or community members did not occur before the government published information on its proposals, which itself had to be requested. And the subsequent public comment period was 28 days.
Boem defends its timeline and consultation process, saying it “understands and respects the deep cultural, environmental and historical connections Pacific Island communities have with the ocean”. The agency insists it has engaged with the governors of American Samoa, the Northern Marianas and Guam, and will take feedback from them and their communities on board.
But Johnson says: “This process is sidestepping local knowledge, it’s sidestepping the local expertise that exists, it’s sidestepping the rights of Indigenous communities to free, prior and informed consent.”
Grassroots organisations are scrambling to fill that gap. Amanda Dedicatoria, a science communicator from Guam and board member of the nonprofit Micronesia Climate Change Alliance, held four days of outreach seminars with students and community members across Guam, Rota, Tinian and Saipan.
“I felt a deep sense of grief from a lot of folks that I interacted with,” she says. “There has been this feeling that islands are not partners in these discussions but are treated as just possessions.”
