Pago Pago, AMERICAN SAMOA — For the fish, sponges and other strange wildlife that make their home on the seafloor dozens of miles from shore, this summer has been unremarkable, barely any different than the decades, centuries or even millennia that have passed by during their long lives. But the decisions being made far away could bring their alien existence to an abrupt end: right now, the U.S. Department of Interior is considering opening this remote, wild ecosystem to deep sea mining. 

What would this decision mean? Putting deep sea ecosystems at risk. 

LIFE IN THE DEEP SEA 

In the darkest depths of the ocean, there is a world of marine life strange and mysterious, a world we have only begun to explore. From the cute to the strange to the ancient, every expedition that visits the deep sea brings back new understandings of the animals that make this extreme environment hope. 

The steep slopes of submarine canyons and ancient volcanoes host vivid deep sea corals and delicate sponges. Lobster, crabs and fish swim between the swaying arms of soft coral and anemones. 

Rocky slopes of canyons and seamounts are not the only parts of the deep sea home to dizzying ecosystems. Hydrothermal vents, rising like chimneys from the seafloor, vent chemicals and heat from beneath the Earth’s crust, host eels and strange mollusks. Sandy flats dotted with potato-sized metallic nodules host sea anemones, soft coral and glass sponges. 

For all that we do know about life in the deep sea, there is even more we don’t: according to NOAA, only 26% of the world’s seafloor had been mapped to modern standards as of 2024. And nearly 80% of species observed during a 3-year NOAA expedition in the Central Pacific were unknown or unidentifiable, and potentially new to science. 

If mining plans go ahead, some of the species we’ve never even seen may disappear before we know they exist. 

THE PROPOSAL TO START DEEP SEA MINING OFF THE COAST OF AMERICAN SAMOA

On May 20, the Department of Interior’s Bureau of Ocean Energy Management (BOEM) announced that it was beginning the process to lease parts of the seafloor near American Samoa for deep sea mining.

This process was kickstarted after a company, Impossible Metals, formally asked the agency to begin the leasing process. 

OCEAN ECOSYSTEMS OF AMERICAN SAMOA 

The U.S. controls over 150,000 square miles of ocean around the American Samoan island chain. The area’s marine ecosystems range from spectacular, relatively intact coral reefs, seabird and sea turtle nesting sites found at Rose Atoll, to hydrothermal vent on Vailulu’u Seamount, to a humpback whale calving ground.

Just as with the rest of the global ocean, the seafloor near American Samoa is understudied. Scientists on the three year NOAA CAPSTONE mission to discover more about ocean ecosystems in the Central Pacific could identify fewer than 20% of the deep sea species spotted in the region. The expedition’s American Samoa cruise alone collected 100 animals, 30 of which the scientists believed to be new to science. 

BOEM is considering leasing a portion of the American Samoan ocean larger than the state of West Virginia for seabed mining. Mining across this region could have fatal consequences for ocean life–both in the mining site itself, and beyond. 

DEEP SEA MINING POSES RISKS TO OCEAN LIFE ON THE SEAFLOOR 

Deep sea mining operations globally have been confined to test runs (so far). But from those runs, we know some of what conventional seabed mining would do to deep sea ecosystems. 

Deep sea mining involves removing minerals from the ocean floor. While there have been a few different types of mining floated over the years, the type of seafloor mining proposed in American Samoa would be the mining of ferromanganese nodules, which are small, potato-size mineral balls formed on the ocean floor.  

Extraction of ferromanganese nodules from the seabed is generally carried out by remotely operated vehicles and mining machines equipped with cutting and suction tools to vacuum up nodules from the seafloor. 

These nodules themselves can host a unique ocean ecosystem. A 2016 survey near another nodule-rich site being considered for mining found 170 distinct types of animals in 11 square miles. Roughly half of the types of organisms identified were found exclusively on the nodules. Removing nodules en masse could mean losing these animals, and even a local ecosystem entirely. 

Recovery from mining for ecosystems this long-lived and slow-growing would take centuries, if it ever occurred. We can see the long-lasting impacts from test mining done in the 1970s off the coast of the southeastern U.S.: a recent scientific expedition to the test site found no recovery of ocean life in the areas stripped of nodules.

Beyond the threat mining poses to the immediate ecosystem, other concerns, like pollution from sediment and wastewater plumes generated by mining, noise and light pollution from continuous operation of mining equipment and disruptions to the broader ocean food web could all have widespread and poorly-understood consequences for marine life far and wide. 

The company putting forward the American Samoa proposal, Impossible Metals, claims that their AI-driven tech will be less harmful to ocean ecosystems than conventional mining equipment. Whether or not that is true, the fact is that mining itself will, by creating massive disturbance for a key part of an ecosystem, by bringing light and noise to a dark and remote part of the ocean, inevitably create problems for ocean life we can only begin to imagine.

WE CAN STILL STOP DEEP SEA MINING FROM BECOMING A REALITY

But deep sea mining is not inevitable: BOEM is only on step one of a longer process to evaluate where, how and if they will move forward with mining off the coast of American Samoa, and will still have to go through several steps before auctioning off mineral rights–and then likely several more before robots begin to mine the deep. 

We have a brief window now to highlight public opposition to deep sea mining before it begins. Not only will this opposition be formally considered by BOEM, it will also signal to the industry and investors that the road ahead for mining will be a rocky one–a signal that might keep the deep sea free from mining equipment in the years to come. 

We’re too late to know what today’s ocean without oil and gas drilling, whaling and overfishing would look like. We can stop this next great threat before it starts, and save one of the planet’s final frontiers — and the amazing life that lives there.