Thanks to the discovery of abundant gold, copper, rare earth elements, and other critical resources for the digital age at deep-sea hydrothermal vents, the deep-sea mining industry is already developing slowly but steadily. Many countries and companies have already secured exploration rights or safe mining rights covering 20% of the world’s deep-sea hydrothermal vent areas.

Forty years ago, scientists discovered extraterrestrial life—not on another planet, but in Earth’s deep ocean—those nutrient-rich, steam-spewing depths heated by volcanic activity.

　　This discovery has redefined the biological possibilities of life, prompting scientists and explorers to begin mapping out what another—indeed, many—worlds might look like. On the seafloor of our planet, there are more than 500 hydrothermal vents, which not only feature smoking chimneys but also volcanic slopes covered with cobalt-rich crusts and seafloor plains teeming with manganese nodules. In a sense, the deep ocean harbors rainforests, mountain ranges, and grasslands of its own—but now, life in these environments is also facing grave threats.

　　Thanks to the discovery of abundant deposits of gold, copper, rare earth elements, and other critical resources for the digital age at deep-sea hydrothermal vents, the deep-sea mining industry is already developing slowly but steadily. Many countries and companies have already secured exploration rights or secure mining rights covering up to 20% of the world’s deep-sea hydrothermal vent areas. The first-ever deep-sea mining operation is expected to take place off the coast of Papua New Guinea in 2018.

　　The ultimate fate of deep-sea hydrothermal vents will depend on how carefully mining methods are carried out. Mining could cause destruction—or it could be done wisely. As long as we care about life beyond humans, we won’t go too far. Deep-sea ecologist Andrew David Thaler recently tweeted: “We’re going to have to make a choice: between a one-time technology and an ecosystem we may never see again.”

　　Thaler spent most of his life studying hydrothermal vents on the seafloor. The nautilus once asked him whether these vents could be saved. How can we inspire people to care about an ecosystem they may never have the chance to visit in person? We’re battling a long-held belief that has persisted since the 17th century—that the deep sea is devoid of life. People tend to think of it as a desert, a wasteland, a place where no exotic creatures could possibly exist, creatures they’ve never seen before. And generally speaking, in such dark, shadowy depths, the organisms aren’t exactly aesthetically pleasing—certainly not among the most charismatic species on Earth. Yet in the hydrothermal vents of the western Pacific Ocean live countless iron-scaled snails and armored shrimp. Their shells are covered with white bristles, and those creatures that look like crabs are actually short, stocky shrimp.

　　Why is it said that deep-sea ecosystems are unique?

　　Because they are so rare and because they spread extensively across the seafloor, each hydrothermal vent is unique. They harbor their own extraordinary communities of organisms, and their species’ growth patterns are particularly fascinating. These dynamic ecosystems represent some of the most biodiverse environments on Earth. Typically, they feature one or two dominant animal species, surrounded by a group of closely related species that consume biomass energy. When you look at photographs of deep-sea creatures, you’ll notice vibrant worms, crabs, limpets, and snails crawling around these vents. Yet, if you examine the ecosystem of this particular region more closely, you’ll discover that it’s dominated by a single species that has evolved to exploit this ecological niche. Despite being ruled by this one species, the ecosystem remains teeming with a wealth of lively and captivating organisms—many of which you simply won’t find anywhere else on the planet.

　　What have we learned from deep-sea hydrothermal vents?

　　When hydrothermal vents were first discovered in the 1970s, we found that hydrogen sulfide emitted from these vents could provide energy for microorganisms—but not directly. Instead, the microorganisms take in hydrogen sulfide and then use it to generate the energy necessary for life. It was at that time that humans began to study and ponder the significance of microbial life. Today, we’ve come to realize that most biological processes in the human body depend on bacteria. We are living organisms built upon bridges formed by countless diverse microorganisms. The reason we’ve been able to unravel this intricate relationship is precisely because of hydrothermal vents—they’ve provided powerful evidence for our research. Thus, these vents are not merely repositories of energy; they’re also places where inspiration abounds. In fact, before the discovery of hydrothermal vent systems, we had no idea that animals could survive without relying on sunlight. We’ve opened the door to an entirely unfamiliar world—essentially, we’ve uncovered a brand-new mode of existence. The knowledge we’ve gained from this discovery is immeasurable.

　　How do hydrothermal vents fit into the grand blueprint of life on Earth?

　　This isn’t something we encounter often, yet it’s precisely the kind of consideration we need to make if we’re serious about safeguarding Earth’s long-term evolution. Hydrothermal vent ecosystems represent an entirely different mode of survival. Should a catastrophe similar to the Cretaceous-Paleogene extinction event—a disaster that wiped out 99.9% of life on Earth—ever occur again, having these alternative life forms would ensure that humanity wouldn’t face total extinction. Or, to put it in more lofty terms: Isn’t the very purpose of life to keep life itself going?

　　What will mining companies bring to the seafloor?

　　Nautilus Minerals has already built several large, Michael Bay–style machines for use on the seafloor. As someone who works both in robotics and in deep-sea conservation, I— the original author— am both amazed and a bit apprehensive. I believe that no underwater machine should ever be fully autonomous; instead, we might consider remotely operated vehicles, some of which would even excavate the seabed. Another suggestion is to lower a huge bucket to the seafloor, scoop up sediment from the seabed, and then pull it up using a rope— a principle similar to open-pit mining.

　　Is deep-sea mining safe?

　　Like other mining operations, deep-sea mining is bound to have some destructive impacts—but we have many ways to minimize those impacts as much as possible. Mining companies are developing tools, laying groundwork, identifying ore deposits and exploration targets, and obtaining the necessary permits. Yet no one has yet actually set foot on the seafloor to begin deep-sea mining; all of them are still searching for methods that are as environmentally friendly as possible. However, until someone actually starts mining in the deep sea, none of us can know just how far they’ll go. The first-ever deep-sea mining venture will be an experiment.

　　However, before deep-sea mining even begins, environmentalists and explorers have already made their way there. Over the past 40 years, they’ve gathered an abundance of data on the region’s ecosystem—including high-resolution seafloor maps and detailed information on the biodiversity around hydrothermal vents. As a result, we now have more opportunities to reflect on how to carry out deep-sea mining responsibly.

　　If mining damages deep-sea ecosystems, can they recover?

　　They are dynamic systems; in some areas, their life cycles last only 10 to 12 years, and they have already evolved to the stage where they can withstand external disturbances. Underwater volcanoes erupt periodically, wiping them out—but these ecosystems eventually recover. So we’ve been thinking: once deep-sea mining begins, it’s still entirely possible for these life forms to return. It’s quite conceivable that you could move into a particular area today and, ten years later, that spot would look completely untouched—no trace at all of any previous mining activity. While other parts of the seafloor might bear long-term scars from the disturbance, the seafloor as a whole would likely appear largely unaffected.

　　However, manganese nodules and cobalt-rich crusts are relatively slow-to-recover ecosystems. The traces left by mining in these areas can persist for centuries, and the disturbance to these regions could have even more far-reaching consequences. Here’s the question: Before we destroy too many deep-sea ecosystems, is there an acceptable threshold for allowable damage?

　　Maybe we’ve never really discovered whether hydrothermal vents on the seafloor are better after all?

　　This issue has been constantly lingering in my mind. Perhaps, in some respects, these biological communities might have fared better if left undisturbed. But I still don’t think they would have fared any better—after all, we’ve already done a great deal of harm to deep-sea ecosystems before we even began to understand them. We drag fishing nets across the ocean floor and use dredges to crush coral reefs in order to raise fish. So, looking at the bigger picture, I really can’t say whether leaving them alone back then would have spared them from destruction. After all, we’ve already destroyed other species and entire ecosystems out of sheer ignorance.

　　However, this idea has indeed kept me awake for several nights. I can’t help but wonder: What exactly are hydrothermal vents doing to these creatures? Although it would be even more tragic to lose them without ever knowing, discovering this sooner gives us a chance to protect them before they’re gone.