“The Deep Sea”: life in the depth of the oceans

Young software developer Neal Agarwal (Twitter: @nealagarwal) created an amazing interactive visualization showing life in the depth of the oceans. Named “The Deep Sea” (click here to see the visualization), the interactive webpage shows the living depths and also the maximum diving points of various animals. Be prepared to be amazed!

The deep sea: living and/or dive depths of some animals and plants

Please keep in mind that the animals and plants listed below are not the only lifeforms to live in these depths – they are just a few examples.

Up to 14 meters (46 feet) deep

Atlantic salmon, Manatee (large, fully aquatic, mostly herbivorous marine mammals also known as sea cows), striped bass, staghorn coral

Up to 40 meters (131 feet) deep

Polar bear, European pilchard, barramundi (Asian sea bass), clownfish

Up to 66 meters (217 feet) deep

Velvet crab, blue tang, Atlantic cod, spiny dogfish, leafy sea dragon, mahi-mahi (or common dolphinfish, a surface-dwelling ray-finned fish found in off-shore temperate, tropical, and subtropical waters worldwide)

Up to 92 meters (302 feet) deep

Flounder (a group of flatfish species), spotted bass, beluga whale, bluefish

Up to 127 meters (417 feet) deep

Great barracuda, killer whale, queen snapper, pelagic stingray

Up to 170 meters (558 feet) deep

Sealion, leptoseris, bull shark, black drum, green sea turtle

Up to 200 meters (650 feet) deep

Atlantic mackerel, dentex

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Ocean twilight zone begins

The ocean twilight zone lies 200 to 1,000 meters (about 650 to 3,300 feet) below the ocean surface, just beyond the reach of sunlight.

Also known as the midwater or mesopelagic, the twilight zone is cold and its light is dim, but with flashes of bioluminescence (light produced by living organisms). The region teems with life. Recent studies suggest that the biomass of fish in the twilight zone maybe ten times greater than previously thought, more than in all the rest of the ocean combined.

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Up to 240 meters (558 feet) deep

Thick-billed murre dive, haddock, wolf eel (a species of wolffish from the North Pacific), chain catshark

Up to 275 meters (902 feet) deep

Kelp, terrible claw lobster, olive ridley sea turtle, great white shark

Up to 310 meters (1,017 feet) deep

Bottlenose dolphin dive, Cockatoo squid

Up to 332 meters (1,090 feet) deep

Gummy shark, human dive

At 332.35 meters, this is the deepest any human has scuba-dived. Set in 2014 by Ahmed Gabr (born 9 November 1972), an Egyptian scuba diver. As of December 2019, Gabr holds the Guinness World Records for both The Deepest Scuba Dive (Male) and The Deepest Scuba Dive in Sea Water. Ahmed dived to a depth of 332.35 meters (1,090.4 ft).

https://www.youtube.com/watch?v=M2ciqRVxmlA

Up to 400 meters (1,312 feet) deep

Blue shark, firefly squid

Up to 450 meters (1,476 feet) deep

Bigeye tuna

Up to 500 meters (1,640 feet) deep

Sea angel, chinook salmon, mako shark

Up to 550 meters (1,804 feet) deep

Emperor penguin dive, swordfish

Up to 600 meters (1,969 feet) deep

Nautilus, sunfish

Up to 650 meters (2,133 feet) deep

Bamboo coral, Japanese spider crab (the largest known crab with a leg span of up to 3.8 meters / 12 feet 5.61 inches)

Up to 700 meters (2,297 feet) deep

Coelacanth

Dubbed “living fossil”, the coelacanth, which is related to lungfishes and tetrapods, was believed to have been extinct since the end of the Cretaceous period (from 145 million years ago -mya- to the beginning of the Paleogene Period 66 mya). The Cretaceous (along with the Mesozoic) ended with the Cretaceous-Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs.

But, on December 23, 1938, a living specimen was found off the east coast of South Africa, off the Chalumna River (now Tyolomnqa). Between 1938 and 1975, 84 specimens were caught and recorded.

https://www.youtube.com/watch?v=4jl_txxYQEA

Up to 750 meters (2,461 feet) deep

King crab

Up to 800 meters (2,625 feet) deep

Giant pacific octopus, giant oarfish (the longest bony fish on Earth, although they commonly measured up to 3 meters/9.8 feet in total length, they can grow a record length of 11 meters/36 feet)

Up to 850 meters (2,789 feet) deep

Monkfish, Pacific cod

Up to 900 meters (2,953 feet) deep

Marrus orthocanna, vigtorniella worm

Up to 950 meters (3,117 feet) deep

Sperm whale dive, leatherback sea turtle

Up to 1000 meters (3,281 feet) deep

Baird’s beaked whale, also known as the four-toothed whale

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Ocean midnight zone begins

The ocean’s midnight zone, also known as the Bathyal zone is a region between one and four kilometers (3,281 to 13,100 feet) deep, where no sunlight at all penetrates the frigid water. With no light, there is no growth of plants or phytoplankton (because of the lack of sunlight necessary for photosynthesis) – all animals are thus predators or scavengers.

Because of the lack of light, some species do not have eyes. Many deep-sea creatures cope by creating light themselves – also known as bioluminescence.

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Up to 1,100 meters (3,609 feet) deep

Anglerfish (which have a large bioluminescent lure used to attract prey in the darkness), phronima, orange roughy (which is notable for its extraordinary lifespan, attaining over 200 years, one of the longest-living animals in the world. Deep-sea life often have elongated life spans.)

Up to 1,200 meters (3,937 feet) deep

Blobfish, the frilled shark, great white shark.

Up to 1,300 meters (4,265 feet) deep

Goblin shark – they sometimes called a “living fossil”, it is the only extant representative of the family Mitsukurinidae, a lineage some 125 million years old.

Up to 1,400 meters (4,593 feet) deep

Bubblegum coral, hatchet fish

Up to 1,500 meters (4,921 feet) deep

Dragonfish, big red jellyfish (many deep-sea species use the color red as camouflage since it is the first color to leave the spectrum as you dive deeper)

Up to 1,600 meters (5,249 feet) deep

Greenland halibut, giant tube worm ( giant tube worms get their nutrients from hydrothermal vents which are formed from seawater passing through extremely hot volcanic rocks. Hydrothermal vents release that are toxic to most animals, but giant tube worms can tolerate extremely high hydrogen sulfide levels.)

Up to 1,800 meters (5,906 feet) deep

Yeti crab, sixgill shark, narwhal dive (a medium-sized toothed whale that possesses a large “tusk” from a protruding canine tooth)

Up to 2,000 meters (6,562 feet) deep

Jewel squid, sea pen, telescope octopus (it is transparent, almost colorless, and has 8 arms. It is the only octopus to have tubular eyes, hence the reason it is commonly referred to as telescope octopus), Mobula ray.

https://www.youtube.com/watch?v=etPPM10JY70

Up to 2,200 meters (7,217 feet) deep

Giant isopod (meals are scarce in the deep-sea, so many deep-sea creatures are adapted to long periods of famine – one giant isopod has been known to survive over 5 years without food in captivity), Greenland shark, colossal squid (largest known squid species, they can grow up to 10 meters / 33 feet, and weigh up to 700 kg / 1.543 lbs)

Up to 2,400 meters (7,874 feet) deep

Barreleye fish, elephant seal dive

Up to 2,600 meters (8,530 feet) deep

Gigantactis, chimaera

Up to 2,800 meters (9,186 feet) deep

Squidworm, black swallower, viperfish

https://www.youtube.com/watch?v=_ax2Vp77hA0

Up to 3,000 meters (9,843 feet) deep

Scaly-foot snail, vampire squid, headless chicken fish (Enypniastes, also known as the “swimming sea cucumber”), zombie worm, Cuvier’s beaked whale dive – the deepest diving mammal

https://www.youtube.com/watch?v=pI6A218YE-Q

Up to 3,200 meters (10,500 feet) deep

Glass sponge, gulper eel (also known as the pelican eel, a deep-sea fish rarely seen by humans), cosmic jellyfish, spotlight loosejaw (Malacosteus)

Up to 3,400 meters (11,155 feet) deep

Harp sponge, cookiecutter shark (it is named after the cookie-shaped wounds that it leaves on the bodies of its prey. This small fish is also known as the cigar shark because of its body shape)

Up to 3,600 meters (11,811 feet) deep

Lizardfish, flabby whalefish

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The average depth of the ocean

3,688 meters (12,100 feet): the average depth of the ocean (according to NOAA, some sources, for example, National Geographic give a slightly different number)

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Titanic’s resting deep

The wreck of the RMS Titanic lies at a depth of about 3,800 meters (12,500 feet).

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Up to 4,000 meters (13,123 feet) deep

Patagonian toothfish (have antifreeze proteins in its tissues to prevent freezing in sub-zero temperatures), the dumbo octopus

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Abyssal zone begins

The abyssal zone is the portion of the ocean deeper than about 4,000 meters (13,123 feet) and shallower than about 6,000 meters (20,000 feet). The zone is defined mainly by its extremely uniform environmental conditions, as reflected in the distinct life forms inhabiting it.

The temperature here is near freezing and very few animals can survive the extreme pressure.

“Abyss” derives from the Greek word “ἄβυσσος”, meaning “bottomless sea.”

Some sources start the abyssal zone from 2,000 meters (6,600 feet) and others from 3,000 meters (9,850 feet).

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Up to 4,050 meters (13,287 feet) deep

Atolla jellyfish

Up to 4,600 meters (15,092 feet) deep

Sea pig, megamouth shark (it is one of the largest shark species with some reaching 8 meters / 26 feet long)

Up to 4,700 meters (15,420 feet) deep

Ninja lanternshark (Etmopterus benchleyi)

Up to 4,800 meters (15,748 feet) deep

Fangtooth, tripod fish

Up to 5,000 meters (16,404 feet) deep

Caridea

Up to 5,100 meters (16,732 feet) deep

Faceless fish

https://www.youtube.com/watch?v=AJst_Ux8bew

Up to 5,300 meters (17,388 feet) deep

Amphipoda

Up to 5,500 meters (18,044 feet) deep

Brittle star

Up to 5,600 meters (18,373 feet) deep

Abyssal spider fish

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The Hadal Zone begins

The hadal zone (named after the realm of Hades, the underworld in Greek mythology), also known as the hadopelagic zone, is the deepest region of the ocean lying within oceanic trenches. The hadal zone is found from a depth of around 6,000 to 11,000 meters (20,000 to 36,000 feet).

Deep-sea trenches form by a process called “subduction” where the Earth’s tectonic plates meet and push together. Life here is sparse – the extreme conditions make survival difficult, but still not impossible.

So little is known about life in these deep environments. Almost every expedition uncovers something new.

More people have been to the Moon than the Hadal Zone.

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USS Johnston (DD-557) shipwreck – the deepest shipwreck ever found

The USS Johnston sunk in WWII. Its wreck was discovered on October 30, 2019, what is believed to be the deepest shipwreck ever located at 6,220 meters (20,406) deep in the Philippine Trench.

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Up to 6,800 meters (22,310 feet) deep

Grenadier

Up to 6,900 meters (22,638 feet) deep

Chiton

Up to 7,200 meters (23,622 feet) deep

Comby jelly – they have been around for 500 million years. Despite looking like jellyfish, they are not closely related.

Up to 8,200 meters (26,903 feet) deep

Hadal snailfish

Up to 8,400 meters (27,559 feet) deep

Cusk eel

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The height of Mount Everest

So far, you have scrolled the height of Mount Everest (8,848 meters / 29,029 feet).

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Up to 10,300 meters (33,793 feet) deep

Hadal amphipod

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Mariana trench – the deepest point of the Earth’s oceans

On January 23, 1960, about 9 years before the moon landing, humans went where they never had before.

The Swiss oceanographer and engineer Jacques Piccard (28 July 1922 – 1 November 2008) and the American oceanographer, explorer and marine policy specialist Don Walsh (born November 2, 1931) reached the floor of the Mariana Trench (the Challenger Deep) using a special submarine named Trieste.

The submarine used a re-breather system that would later be used in spacecraft. There was barely enough space inside the pressure sphere for both of them.

The descent progressed without incident until 9,150 meters (30,000 feet), when the crew heard a loud crack that shook the entire vessel. They had no idea what it was.

Even at these unfathomable depths, Jacques and Don could still see life out the window. Life can survive in unimaginable environments.

The immense pressure of the deep sea means any mistake would mean certain death. They continued the dive, however, and after 4 hours and 47 minutes of anxiety and claustrophobia, they finally touched down in “snuff-colored ooze” at 10,916 meters (35,813 feet).

On March 26, 2012, Canadian film director James Cameron (born August 16, 1954) has reached the bottom of the Mariana Trench in the submersible vessel Deepsea Challenger. He became the first person to do this in a solo descent and is only the third person to do so ever.

https://www.youtube.com/watch?v=UHUF0m28i0U

The depth of the descent was measured at 10,916 meters (35,813 feet); later, more accurate, measurements during 1995 found the Mariana Trench to be slightly less deep at 10,911 meters (35,797 feet).

Data suggests that microbial life forms thrive within the trench.

Sources

• “Ocean Twilight Zone” on the Woods Hole Oceanographic Institution website
• Ahmed Gabr on Wikipedia
• Coelacanth on Wikipedia
• “Welcome to the Midnight Zone” on aquarium.co.za
• Goblin shark on Wikipedia
• Cookiecutter shark on sharksider.com
• Hadal zone on Wikipedia
• Jacques Piccard on Wikipedia
• Don Walsh on Wikipedia