Photograph by Awashima Marine Park, Getty Images
Humans rarely encounter frilled sharks, which prefer to remain in the oceans’ depths, up to 5,000 feet (1,500 meters) below the surface. Considered living fossils, frilled sharks bear many physical characteristics of ancestors who swam the seas in the time of the dinosaurs. This 5.3-foot (1.6-meter) specimen was found in shallow water in Japan in 2007 and transferred to a marine park. It died hours after being caught.
Giant Spider Crab
Photograph by David Doubilet, National Geographic
Thought to be the largest arthropods on Earth, giant spider crabs spend their time foraging on the ocean floor up to a thousand feet (300 meters) deep. These rare, leggy behemoths, native to the waters off Japan, can measure up to 12 feet (3.7 meters) from claw tip to claw tip. This five-foot (1.5-meter) specimen was photographed in Japan’s Sagami Bay.
Atlantic Wolffish Pair
Photograph by Jonathan Bird, SeaPics
The sinister-looking Atlantic wolffish makes its home in the rocky coastal depths up to 1,600 feet (500 meters) below. Reaching 5 feet (1.5 meters) long, wolffish have conspicuous dentition suited to a diet of hard-shelled mollusks, crabs, and sea urchins. This mated pair was found in a deep-sea den off the coast of Maine.
Photograph by David Wrobel, SeaPics
The nightmarish fangtooth is among the deepest-living fish ever discovered. The fish’s normal habitat ranges as high as about 6,500 feet (2,000 meters), but it has been found swimming at icy, crushing depths near 16,500 feet (5,000 meters). Fangtooth fish reach only about six inches (16 centimeters) long, but their namesake teeth are the largest, proportionate to body size, of any fish.
Photograph by Paul Nicklen, National Geographic
Six-gill sharks, like this one off the coast of Vancouver, cruise the ocean floor during the day, sometimes as deep as 8,200 feet (2,500 meters), then move toward the surface at night to feed. They can reach impressive lengths of 16 feet (4.8 meters) on a diet of other sharks, rays, squids, crabs, and occasionally seals.
Giant Tube Worms
Photograph by Emory Kristof, National Geographic
Crushing pressure, freezing temperatures, and zero sunlight isn’t enough of a challenge for giant tube worms. They’ve adapted to thrive at the edge of hydrothermal vents, which spew superheated water saturated with toxic chemicals. This colony was photographed 1.5 miles (2.4 kilometers) below the ocean’s surface on the East Pacific Rise near the Galápagos Islands.
Photograph by Kim Reisenbichler, National Geographic
Vampire squid is an apt name for a creature that lurks in the lightless depths of the ocean. Comfortable at 10,000 feet (3,000 meters) below the surface, these diminutive cephalopods navigate the blackness with eyes that are proportionately the largest of any animal on Earth. The species gets its name from its dark, webbed arms, which it can draw over itself like a cloak. It occupies the mesopelagic and bathypelagic regions of temperate and tropical world oceans. The animal’s physiology has adapted to enable it to live at the very low oxygen levels found within the oxygen minimum layers of these regions.
Photograph by David Wrobel, SeaPics
The Pacific viperfish has jagged, needlelike teeth so outsized it can’t close its mouth. These deep-sea demons reach only about 8 inches (25 centimeters) long. They troll the depths up to 13,000 feet (4,400 meters) below, luring prey with bioluminescent photophores on their bellies.
Photograph by Espen Rekdal, SeaPics
An orthodontist’s dream, an Atlantic wolffish displays the hardware it uses to crush mollusks, shellfish, and sea urchins. These tough-looking predators swim as deep as 2,000 feet (600 meters) and range from the Scandinavian coast to Cape Cod to the Mediterranean.