Fantastic Creatures of the Deep

You don’t need to get kicked out of Hogwarts and travel the magical universe to find fantastic beasts with otherworldly abilities. The natural realm around us is teeming with mystery, wonder, and surprise.

No wands required to discover and enjoy these amazing creatures of the deep, but you will need the help of incredible teams of deep-sea scientists who help bring these creatures to light. Here are a few of our favorite deep sea discoveries, and where you can find them. We suspect they might be fantastic enough even for Newt Scamander.

Deep Sea Forests of Sponges

Breed: Family Rossellidae — the glass sponges

Farreid glass sponges are visible in the foreground of this fairly high-density sponge community found at about 2,360 meters (7,740 feet) depth. Corals were also present, but in lower abundance. Iridogorgia and bamboo coral are in the background. Image courtesy of the NOAA Office of Ocean Exploration and Research, 2017 Laulima O Ka Moana.
Left: This glass sponge was imaged on an unnamed seamount just outside the Papahānaumokuākea Marine National Monument. Credit: NOAA Office of Ocean Exploration and Research; Right — This pink precious Hemicorallium in the family Coralliidae, found at ~2,400 meters (~7,875 feet), had most of its tentacles drawn in.

Appearance: Glass sponges get their name from the beautiful and often intricate skeletal structures they create out of silica — the same material found in glass. Most are small, but i The giant organism measured over 11.5 ft (3.5 m) long by 6.5 ft (2.0 m) wide — the largest ever recorded.

“Magic” Abilities:

  • Ability to withstand great pressure: These sponges are often found at unbelievable depths in the ocean.
  • Ability to improve the world around them: Sponges helps filter ocean water and very large specimens actually provide habitat for other ocean creatures.

Dangers: The loss of stable deep water habitat.

Typical Habitats: Glass sponges tend to live in very deep ocean environments around the world including the seamounts surrounding

Explore more:

The “Ghost” Octopod of Papahānaumokuākea

While exploring at depths of over 4,000 meters northeast of Necker Island in the Hawaiian Archipelago, Deep Discoverer encountered this ghostlike octopod, nicknamed Casper, which is almost certainly an undescribed species and may not belong to any described genus. Credit: NOAA Office of Ocean Exploration and Research

Breed: Unknown member of the Suborder Incirrata Octopoda — aka Casper: the ghost octopod.

The “ghost” octopod slowly moves on a flat ocean shelf.

Appearance: This ghost-like octopod surprised and delighted scientists in 2015 when it was discovered by the 2.5 miles down in Papahānaumokuākea The ghostly octopod gets is pale look from a complete lack of pigmentation cells.

Magic Abilities:

  • The ability to live with almost no muscles. At those depths, food is scarce and muscles take work to grow.
  • The ability to stay hidden. This octopod is the first of its kind to be seen and described. Before 2015, scientists had no idea they existed floating deep in the depths of the ocean.

Dangers: The loss of stable deep water habitat.

Typical Habitats: Very little is known of these secretive creatures. They have been observed in deep waters near areas where there is a hard substrate for deep sea sponges. The ghost octopod has been observed laying their eggs on the stalks of dead glass sponges.

Explore more:

Palmyra Parrotfish : Colorful farmers of the sea (that grind coral and poop white sand)

Parrot fish swim and graze in the coral reef of Palmyra Atoll National Wildlife Refuge. Photo by Kydd Pollock.

Breed: Family: Labridae

Appearance: When looking at parrotfish, it isn’t hard to imagine where the name comes from. Their fused teeth give them a parrot-like beak and their bright color patterns can be quite fantastical. With over 60 species of parrotfish, they can range between 1–3 feet in length and come in various colors. They can be red, yellow to blue, green, or from gray to brown, and black. These colors may change based on age and sex.

Some species may have vertical, steep foreheads for head-butting coral to stir up algae or for ritually head-butting each other.

Parrotfish swimming through coral reef at Palmyra Atoll. Video by Kydd Pollock

Magic Abilities

  • Ability to change sex from female to male.
  • Ability to make white sand beaches. Parrotfish bite off coral with the algae, which is ground into a fine sand with molar-like teeth in their throats. This ground coral moves through the digestive tract and comes back out onto the reef as white sand. They are responsible for making 70% of white sand beaches and making habitats for shrimp and crabs. A large male can create over a ton of sand per year.
  • They gorge on a single area and rotate between them, guarding territories for the next harvest.
  • Ability to create a mucus “sleeping-mask” bubble to mask their scent from predators.

Danger: Loss of coral reef habitat.

Typical Habitats: Coral reefs worldwide, including

Explore more: You can take a in the waters of Palmyra Atoll.

Snailfish of the Mariana Trench: The unsuspecting, deepest living fish

Breed: Pseudoliparis swirei

A CT scan of the Mariana snailfish, showing a side view. The green shape, a small crustacean, is seen in the snailfish’s stomach.Image credit: Adam Summers/University of Washington

Appearance:. Unlike other fishes of the deep, these snailfish have no scales, no big teeth, and are not bioluminescent. They have a slightly pinkish-white skin that is transparent, and are about twice the size of a cigar, with the tail making up almost two thirds of its length.

Mariana snailfish in the Mariana Trench at depths of 7,000 to 8,145 meters. Video courtesy of SOI/HADES/University of Aberdeen (Dr. Alan Jamieson)

Magic Abilities

  • Ability to withstand more water pressure than the weight of 1,600 elephants.
  • Ability to chemically adapt to these deep conditions. They have evolved to keep their proteins stable: their enzymes to keep functioning and membranes to keep moving.


Pollutants from degrading pieces of plastic are being found in crustaceans’ stomachs. Snailfish may feed on these crustaceans.

Typical Habitats

Lives roughly around 6,898 to 7,966 meters down in the Mariana Trench, or as deep as two Grand Tetons of Wyoming is tall.

Explore more:

Across the vast Pacific Ocean, the U. S. Fish and Wildlife Service works with partners in Hawaii, Guam, American Samoa, the Commonwealth of the Northern Mariana Islands, National Oceanic and Atmospheric Administration, the Office of Hawaiian Affairs, and other partners to protect and conserve some of the largest protected marine areas on the planet.

You can can join in on future deep sea explorations by following

Written by Amy Olliffe, Elena Fischer, and Holly Richards
External Affairs Office for the U. S. Fish and Wildlife Service in the Pacific

Updates from the U.S. Fish and Wildlife Service

The U.S. Fish and Wildlife Service is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people.

U.S. Fish & Wildlife Service

Written by

We’re dedicated to the conservation, protection and enhancement of fish, wildlife and plants, and their habitats.

Updates from the U.S. Fish and Wildlife Service

The U.S. Fish and Wildlife Service is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people.

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade