Exploring the Deep Sea

Right next to the coast is the continental shelf, the submerged part of the continent. This area is characterized by shallow water and mostly exists within the sunlit epipelagic zone. Traveling away from the coast the seafloor will begin to slope down through the mesopelagic and bathypelagic zones into deeper depths.

• The mouth is loosely hinged and can be opened wide enough to swallow an animal much larger than itself; however, it usually only eats small crustaceans.
• Animals like mussels and crabs come to feed on the special bacteria by the lake’s edge, and often there are whole communities that live along the shore.
• A siphonophore, these animals are made up of multiple units, each specialized for a function like swimming, feeding, or reproduction.
• This mostly includes waste, such as dead and decomposing animals, poop, silt and other organic items washed into the sea from land.
• Under the light of the moon they feast on the phytoplankton that grew during the day.
• When most of us picture the ocean, we imagine turquoise waves, colorful reefs, and shoals of darting fish.
• Marine snow clumps are also swarming with microbes—tiny organisms ranging from algae to bacteria—that form communities around the sinking particles.

According to a Deep Sea commonly used definition, it begins where the comparatively flat seafloor of the coastal regions segues into deeper and steeper areas. Depending on the respective region, this can be at very different water depths. In the Antarctic, for instance, the tremendous ice masses weigh down the continent considerably. Its margin, referred to as the continental shelf, can extend up to 500 metres below the water’s surface; only after this point does the deep sea begin. In contrast, in most other regions, this transition begins just 200 metres below sea level. The hadalpelagic is the very deepest part of the ocean that includes the ocean trenches.

Tools & Technology

At 1,000 meters (3,280 feet), the temperature is about that of a refrigerator. Deeper down, it gets colder and quieter near the ocean seabeds, some of which are paved with metallic gray rocks, resembling underwater cobblestone streets. Each rock started as something small — like a shark tooth or tiny fossil.

Bizarre (and Terrifying) Deep-Sea Creatures

Scientists think that they might be an adaptation to living in darkness in a food-scarce environment. The giant chompers allow the 6-inch fish to grab on to anything unlucky enough to pass by, even prey much larger than itself. The same explanation may apply to deep-sea creatures like viperfish, dragonfish, and anglerfish. The top 200 meters of the ocean are known as the sunlight, or euphotic, zone. Plants, who convert the sun’s energy into food via photosynthesis, form the basis of the food chain at these depths, where there is indeed sunlight. At 200 meters depth, we enter the twilight zone, where light starts to decrease rapidly.

Noise and light pollution

Keep one eye out for Bonnelli’s cock-eyed, which clearly have one eye much bigger than the other. If disturbed, it will curl its arms up outwards and wrap them around its body, almost turning itself inside-out and, exposing spiny projections called cirri. They also have amazing bioluminescent displays with light organs on the tip of each arm and at the base of each fin. When disturbed, these can glow and pulse and the arms may writhe so that it becomes very difficult to tell one end of the vampire squid from the other. In addition to feeding, creatures of the deep use light in flashy displays meant to attract mates.

• Ghostshark is one of the common names for chimaeras, but they aren’t actually sharks at all.
• There are vibrant seamounts (underwater mountains, like those found off the coast  of Chile), teeming with corals, sponges, and fish, as well as hydrothermal vents, sometimes likened to hot springs on the ocean floor.
• As this material drops deeper and deeper, the particles can grow in size as smaller flakes clump together.
• Nodules also host a vast array of microbial communities that play a critical role in nutrient and carbon cycling.
• The AWI crawler TRAMPER can operate at depths of up to 6,000 metres and remain submerged for up to a year.

Its eyes are bright green and barrel-shaped (hence its name) and point straight up. The green hue might filter out certain wavelengths of light and aid them in seeing other creatures’ bioluminescence. Research dives by the Monterey Bay Aquarium Research Institute in 2009 revealed that the fish can also rotate their eyes to face ahead, which probably helps them forage for zooplankton more accurately. But why it developed such extreme adaptations to life in the ocean’s twilight zone is still a bit of a mystery. There were colonies of giant tubeworms (Riftia pachyptila) crowding the vents.

Pressure

Not much is known about them, but they dwell at depths ranging from a few hundred meters to at least 2.200 kilometers. They are so big that they probably caused the belief in the Kraken — a legendary sea monster of giant proportions that is said to dwell off the coasts of Norway and Greenland. Let’s change things up a little and look at this species — well, group of species actually.

Carranza and other scientists had first detected the coral reefs in 2010 using mapping technology. The team found that they were healthier, larger, and richer with life than they anticipated, and the tallest coral mound was just over 130 feet high. One of the largest reef complexes discovered is 984-feet-deep and covers the length of about 180 soccer fields.
The geography of a canyon also creates currents of moving water that suspend the amassed nutrition into the water column, often even reaching up into shallower, sunlit depths where photosynthetic algae grow. Krill and crustaceans called amphipods thrive off the phytoplankton, and it is the masses of these zooplankton that attract tuna, swordfish, and sharks to canyons. These worms house bacteria within their “roots” that take advantage of the sulfur in the bones to make energy in a process called chemosynthesis.

Cobalt-rich crusts

The area of the ocean between 650 and 3,300 feet (200-1,000 m) is called the mesopelagic. Barely any light filters down to these depths, and yet still life thrives here. About 90 percent of the world’s fish (by weight) live in the mesopelagic—about 10 billion tons of fish. The bristlemouth fish alone may number at about a quadrillion, making them the most numerous family of vertebrates (animals with a backbone) in the world.