Deep Sea

On the other hand, the more food-limited Ryukyu Trench at this depth was dominated by very different communities with sea cucumbers nearly absent. Deep-sea creatures in the trenches of Japan’s volcanically active “Ring of Fire” belt are rapidly adapting to immense depths, scientists found. Noise and light pollution could seriously disrupt species, such as whales and other deep-diving or deep-dwelling animals, that use noise, echolocation or bioluminescence to communicate, find prey and/or escape predators. Alongside legal and extractive frameworks, alternative imaginaries—such as those inspired by Drexciyan mythology—disrupt dominant logics of ownership and exploitation.

• While exploratory mining to test equipment has occurred at a small scale, deep-sea mining has not yet been undertaken commercially.
• Packages and bags have been discovered that have apparently been on the seafloor for decades, virtually untouched by time.
• The ocean has absorbed over 90% of the excess heat generated by the burning of fossil fuels; much of this heat has been transported to the deep by ocean currents.
• The latest round of talks ended in July 2025, and negotiations will resume in 2026.
• Sperm whales, southern elephant seals, leatherback sea turtles, emperor penguins, and beaked whales are especially good divers.
• By the time the ocean returned to that region, sediment had covered the salt, isolating it from the seawater.

Seafloor Habitats

Proponents of deep-sea mining argue that it can help meet the world’s pressing need for critical minerals, which will likely only continue to grow as countries invest more in decarbonization, digitization, defense and infrastructure. Estimates suggest that global demand for nickel, cobalt and rare earth elements may double by 2040 in a net-zero emissions scenario. Several studies have concluded that there is no shortage of mineral resources on land, but the world still faces significant hurdles in locating viable reserves and quickly scaling up mining and processing operations.
While there has been commercial interest in these minerals for decades, recent advancements in technology have made it feasible to mine these areas by sending vehicles down to harvest mineral deposits from the seafloor. The sensory modes through which the deep sea has been scientifically understood have evolved over time—from the tactile to the auditory and, finally, to the visual (Helmreich 2009). This progression has made the submarine world simultaneously more comprehensible and more fantastical (Helmreich 2009). To gain experience of the deep sea, anthropologists and other social scientists rely on the same technical aids as the oceanographers with whom and through whom they study. This medium of engagement ‘blurs distinctions between inside and outside, artifice and environment’ and is simultaneously ‘hyper-present and invisible’, much like the water surrounding the submarine itself (Helmreich 2009, 214).

Sea turtles

A few countries have already approved permits to explore mineral resources in their own domestic waters (known as “exclusive economic zones,” or “EEZs”). However, most deep-sea mining interest is concentrated in international waters. This means the industry’s future will largely hinge on how the ISA decides to regulate it. Despite years of negotiations, the ISA and its membership have been unable to agree on rules that will govern commercial mining operations in international waters.
However, mining them is a technically complex and correspondingly expensive undertaking. As such, there have only been pilot projects; there is no commercial mining network. But many countries and private companies have already applied for exploration licenses with the United Nations’ International Seabed Authority. For observations, experiments and taking measurements directly on the seafloor, “bottom landers” are a good choice – devices that, without a cable, sink down to the seafloor, where they take pictures and conduct pre-programmed experiments.
A second has been observed on video, however, it has yet to be captured and formally described. Despite the remoteness of the hadalpelagic, humanity still finds a way to interfere—plastic debris has been found at the bottom of the Mariana Trench. Oceanographers divide the majority of the ocean midwater into five broad zones. The very deepest depth of the ocean is roughly 2,000 meters deeper than Mount Everest is tall—36,070 feet deep (10,994 m)! Each zone has a different mix of species adapted to its specific light level, pressure, temperature, and community.

Threats to underwater cultural heritage: deep-sea mining

• For example, the AWI’s Ocean Floor Observation and Bathymetry System (OFOBS) consists of a downward-pointing camera and flash, together with a sonar system that scans the seafloor topography to its left and right; all of which is housed in a protective metal frame.
• When the phytoplankton are gone, the animals that grew quickly to eat them die and sink to the seafloor.
• In 1989, eleven square kilometres of the Pacific seafloor were churned up in an area roughly 650 kilometres southeast of the Galápagos Islands to simulate the mining of manganese nodules.
• The aim is to build the largest-ever dataset of these habitats and help shape legal protections.
• There, an estimated 60 million nests are spread across 240 square kilometres, an area the size of 36,000 football fields.

The extreme saltiness causes significantly denser water than the average ocean water and, like water and air, the two do not mix. The salt difference is so definitive that sitting above the brine lake, you can visibly see the lake’s surface—even waves when the lake is disturbed. Salinity is remarkably constant throughout the deep sea, at about 35 parts per thousand.9 There are some minor differences in salinity, but none that are ecologically significant, except in largely landlocked seas like the Mediterranean and Red Seascitation needed. Undiscovered oil reserves in the region have been estimated at 801.5 million cubic metres (5,041 million barrels). Undiscovered gas reserves in the region have been estimated at 3,180 billion cubic metres (112,349 billion cubic feet).

Temperature

This, he said, could wipe certain pelagic species out before deep-sea mining even Deep Sea begins on a commercial level. For Warwick, the bigger concern is for benthic species, which are slower growing. “Because of their habitat use, deep-sea mining could be almost as great as deliberate killing of them through fishing,” Warwick told Mongabay. While commercial deep-sea mining has not yet started, some companies are looking to launch operations in the near future.

Deep seapdf

However, because the highest concentration of rare earths is thought to be in international waters, the ISA holds significant regulatory power over deep-sea mining. Yet, the ISA is still developing its official policy on how it will approach deep-sea mining regulation, and it has not approved any extraction projects. As of August 2025, the ISA has only issued 31 exploration contracts, which are 15-year contracts that allow countries and corporations to assess the potential for rare earths in certain approved locations.

Rapidly adapting sea creatures found in Japan’s deepest ‘Ring of Fire’ trenches

Fish, too, find shelter within the canyon walls, and also a good place to catch a meal. Natural light does not penetrate the deep ocean, with the exception of the upper parts of the mesopelagic. Since photosynthesis is not possible, plants and phytoplankton cannot live in this zone, and as these are the primary producers of almost all of earth’s ecosystems, life in this area of the ocean must depend on energy sources from elsewhere. Except for the areas close to the hydrothermal vents, this energy comes from organic material drifting down from the photic zone. The sinking organic material is composed of algal particulates, detritus, and other forms of biological waste, which is collectively referred to as marine snow. Deep-sea fisheries take place between depths of 200 and meters, and target species on continental shelves, seamounts and ocean ridges using bottom and deep mid-water trawls, gillnets, longlines and pots.