Deep Sea Reefs and What Lies Below the Surface

Discover the ecosystems deep below the ocean's surface and some of the most fascinating creatures that live here.

Apr 10, 2023byDonna Hobson
deep sea reefs below ocean surface

Along with the ecosystems of deserts, rainforests, and savannahs, deep-sea coral reefs are some of Earth’s most fascinating and diverse ecosystems. Like tropical corals near the surface, the deep-water coral reefs provide essential habitats for marine life, including fish, mollusks, and other invertebrates.

However, due to the depth and darkness of these environments, some as far as 6600ft, they can be challenging areas for scientists to get to and explore. However, technological advances make it possible to explore these unique habitats from afar using remotely operated vehicles (ROVs). Here’s what we’ve discovered about these fascinating ecosystems so far.

Deep Sea Reefs

deep sea coral reef

The deep ocean is a vast, mysterious place that makes up most of our planet’s living space. It accounts for 95% of all the habitable space on Earth and is home to an array of fascinating creatures, from bioluminescent jellyfish to giant squid. Despite its importance, we know little about what lies beneath the surface. Scientists are just beginning to uncover the secrets of this hidden world and its complex ecosystems. Here are just a few of the strange and wonderful creatures that lurk in deep sea coral reefs.


giant oarfish swimming next to human

The oarfish is an elusive deep-sea fish known to inhabit the ocean’s depths for centuries. It is one of the longest bony fishes in the world, reaching up to 36 feet in length and weighing up to 600 pounds. Its long, thin body is covered in silvery scales, and its head is crowned with a single crest.

Oarfish are rarely seen alive due to their deep-water habitat but have been known to wash ashore on rare occasions. They are believed to be indicators of seismic activity and can be found worldwide in tropical and temperate waters.


Cystisoma clear sea creature

Cystisoma is a type of clear fish that can hide in plain sight. It has transparent skin and scales, making it difficult to spot in the water. This fish species has been around since ancient times and can be found in many freshwater bodies worldwide.

Cystisoma are known for their ability to blend into their environment, making them excellent predators as well as prey.


chimaera ancient shark relative

The Chimaera is an ancient relative of the shark that has been around since the age of dinosaurs. It has unique features that make it stand out from other sharks. One of these features is the electrical sensors around its mouth, which it uses to detect prey and predators in its environment.

This allows it to hunt more effectively than other species and gives it an advantage in the ocean. The Chimaera also has a long lifespan compared to other shark species, making them a valuable asset in marine ecosystems.

Bioluminescence – Dragonfish and Deep-Sea Anglerfish

dragonfish bioluminescent lure

Bioluminescence is thought to be used by deep sea creatures for various reasons, including communication with other species, locating prey, deterring predators, and attracting mates. Deep sea creatures can produce light through specialized organs called photophores which contain proteins that react with oxygen to produce light.

Dragonfish, also known as stomiids, are a unique species of deep-sea fish that can produce light through bioluminescence. This remarkable trait allows them to survive in the ocean’s dark depths and hunt for food. Dragonfish use their bioluminescence to attract prey by luring them with a bright glow while at the same time hiding from predators. They can also use it to communicate with other dragonfish in their environment.

The deep-sea anglerfish is a fascinating creature living in the ocean’s depths. It has evolved to survive in this dark, hostile environment by using bioluminescence – light produced by living organisms – to attract its prey. This unique ability allows it to hunt and feed in an environment where other creatures struggle to survive.

Dangers of Commercial Fishing

coral damage caused by commercial fishing nets

Commercial fishing is a significant threat to deep-sea coral reefs. As the demand for fish increases, fishermen are pushing deeper into deeper waters and targeting species living in or near coral reefs. This has led to increased destruction of these fragile habitats, resulting in the loss of biodiversity and ecosystem services.

The destruction of deep-sea coral reefs can have severe consequences for marine life, as they provide essential habitat and food sources for various species. In addition, it can also disrupt global oceanic cycles by reducing the amount of carbon dioxide absorbed from the atmosphere.

Furthermore, commercial fishing activities can also cause physical damage to coral reef ecosystems by dredging up sediment from the seafloor and damaging fragile corals with trawling nets or longlines. This not only affects the immediate area but can have far-reaching effects on other areas as well.

Donna Hobson
byDonna Hobson

Donna believes that keeping a pet is the key to a happy life. Over the years, many creatures have passed through her home - Sooty the cat, Millie the rabbit, Stuart (Little) the guinea pig, and Trixie the tortoise, alongside her pet goldfish, Zippy, who lived to the grand old age of 24 years! She currently resides with her black kitten Jinx and an aquarium full of fish and snails to entrance them both. When she is not looking after her pets, Donna enjoys researching and writing the answers to all your pet-related wonders.