The global scientific community has a far better understanding of the outer reaches of our galaxy than the depths of Earth’s oceans. In fact, we have sent four-times more scientists to the moon— 239,000 miles away—than we have to the ocean’s deepest documented point just 6.6 miles beneath the surface of the Pacific.
With so much ocean left to explore, it’s no wonder that new species are discovered with each expedition to the deepest trenches of our oceans. Scientists are still learning about the unique adaptations that allow life to thrive thousands of feet below sea level under intense pressure in the cold, pitch-black abyss. In fact, when it comes to marine animals, it seems the deeper you go, the weirder—and more remarkable—things get!
Japanese Spider Crab
Found in the Pacific Ocean near Japan at depths of nearly 2,000 feet below sea level, the Japanese spider crab looks like a work of science fiction. With a leg span of up to 13 feet and an adult weight of about 40 pounds, these spindly giants are the world’s largest crabs and can live for up to 100 years. Like their smaller crab cousins so popular here in the Chesapeake region, they are scavengers but they’re also intensely clever. In fact, they are known to hide from predators through camouflage by adorning their craggy carapaces with shells, kelp and other found items to blend into surrounding formations.
Diving another 1,000 feet, we encounter the vampire squid. Although it shares characteristics with both squid and octopuses, scientists have actually classified it into its own group, but don’t worry; it does not want to suck your blood. It was named for its dark coloring and the cape effect created by the skin that connects its eight arms. It does not expel ink like its squid cousins. Instead, it ejects a sticky, bioluminescent mucus that glows for up to 10 minutes, providing light in the dark middle regions of the sea, confusing its predators and allowing the vampire squid to escape attack.
About 7,000 feet beneath the surface, the deep-sea anglerfish exists in almost total darkness where the female of the species can choose to hide or reveal a glowing bioluminescent “lure” that bobs forward from her head. The lure is actually the bulb-like tip of a spiny extension of the dorsal fin. When exposed and glowing, the lure allows the deep-sea angler to attract a mate—or to guide prey straight into its large jaws ringed with long, sharp teeth.
Exploring 2 miles below the surface of the water—anywhere between 10,000 and 15,000 feet—scientists discovered the Dumbo octopus in 2005. These cephalopods can survive pressures of up to 5,000 pounds per square inch in the dark, icy waters they call home. The Dumbo octopus was named for Disney’s adorable Dumbo the elephant because it flaps two ear-like fins to move. However, notable “ears” are where the similarities end since most Dumbo octopuses only grow to be about a foot long.
Plunging even deeper to about 26,000 feet beneath sea level toward the Atacama Trench—just off the coast of Peru and Chile—you might encounter the snailfish. The teeth and inner ear bones are the hardest parts of this flabby, translucent fish. The snailfish is held together by the chilly temperature and high pressure of the deep ocean—They thrive in an environment that is inhospitable to most living creatures. According to researchers, the its body melts away when brought to the surface!
Since reaching them requires such intense effort, it is hard to understand everything we would like to know about the remarkable animals of the deep ocean. However, what we do up here on the surface makes a difference. In 2019, a massive expedition to explore the deepest point in each of Earth’s oceans known as the Five Deeps Exploration discovered candy wrappers and a plastic bag in the Mariana Trench.
In order for exploration to continue—and for marine life to thrive at any depth—we must treat our oceans with the greatest respect.