One of the most significant animal habitats is the ocean, which makes up over three-quarters of the surface of the planet. Around 230,000 species have been reported there, and there are likely many more that haven’t been found yet.
Over a million species are thought to exist in the world’s seas, according to biologists.
There is an alphabetical list of ocean creatures on this page, along with information on each animal. Additionally, there are connections that you may use to access additional resources, as well as a FREE quiz to test your understanding.
Members of the animal genus Crustacea include crabs. Barnacles, krill, lobsters, and crayfish are examples of other crustaceans. The majority of crustaceans are marine creatures, but some, like woodlice, have adapted to life on land.
There are five pairs of limbs on a normal crab. While the other four pairs are utilized for mobility, the front pair is often converted into pincers. Crabs rarely move forward, preferring to move sideways.
Exoskeletons on crabs provide them with protection. The crab periodically molts as it develops, removing every part of its body—including its legs—from its previous shell. Because of the softness and expandability of its new shell, the crab has opportunity to develop further.
The Arctic Ocean and subarctic seas of the Northern Hemisphere near the North Pole are home to a scattered population of the enormous flippered walrus. The walrus is the only surviving species in the genus and family Odobenus.
Peacock Mantis Shrimp
The candy-colored peacock mantis shrimp, which is found in the Indian and tropical western Pacific oceans, is renowned for its capacity to fast “punch” prey with its front two limbs.
The worldwide ocean preservation advocacy organization Oceana claims that this shrimp has one of the swiftest motions in the animal kingdom, one that is powerful enough to shatter the glass of an aquarium. But don’t worry; they mainly just use their steel fists to crack open mollusks and chop up crabs.
Among all vertebrates, these aquatic creatures have the most astounding species variety. According to reports, 34,300 different fish species have been identified to date.
Fish have unique colors, forms, physical characteristics, coping mechanisms, and lifestyles. In contrast to sharks and whales, which humans should avoid at all costs, other fish, like goldfish, may be rather sociable and can even be kept as pets.
Water birds of the cormorant family range in height from 46 to 51 cm and weigh between 1.1 and 1.5 kg.
They are widespread around the globe and prefer freshwater settings close to the shore, such as lakes, rivers, estuaries, and marshes.
Large seabirds are albatrosses. They can fly large distances with minimal energy because of their long, thin wings.
About 21 different species of albatross exist (scientists disagree over the exact number). They make up the Diomedeidae family together.
On this website, you may learn more about several animal groups such families, orders, and species: Classification of Animals
The wandering albatross is the biggest species of albatross. The largest wingspan of any bird, at 3.7 meters (12 feet), belongs to it. (The nearly related southern royal albatross has a comparable size.)
The albatross’s wingspan is equivalent to two tall men laying head to toe on the ground.
Fish, squid, krill, and zooplankton are the main foods for albatrosses. They may hunt for food on the ocean’s surface or plunge underneath to get their prey.
The majority of an albatross’ life is spent at sea. Some people have been known to travel three times a year, all the way across the southern hemisphere!
In reality, seals are a species of pinniped that also go by the name. They are saltwater animals that mostly consume fish and squid. Eared seals and Earless seals are the two varieties of seals. The Earless seals, sometimes referred to as real seals, have ears that are buried behind the skin.
Pink See-Through Fantasia
The pink see-through fantasia, whose name sounds like a piece of erotic underwear, is really a sea cucumber that can be found 1.5 miles under the surface of the Celebes Sea in the western Pacific, east of Borneo.
The intriguing sea cucumber, which was first identified in 2007, has a survival strategy that suggests vast evolutionary history: it uses bioluminescence to fend off predators. The translucent skin of the pink see-through fantasia, which makes its anus, mouth, and intestines all visible, is how it gets its name.
The Grimpoteuthis is one of the world’s prettiest octopuses. They appear innocent because of their small size and large, sunken eyes.
These octopuses have fins that resemble ears and a button-nose. The Dumbo Octopus got its name because of how similar it looked to Dumbo the Disney character. There are now 15 species of dumbo octopus that have been identified, and they are all members of the deep-sea umbrella octopus genus.
The large antennae, spiny shell, and sharp claws of lobsters are well recognized. On the ocean floor, these are crustaceans that live. Lobsters have 10 legs for locomotion and two enormous claws for self-defense or catching prey.
The Lophiiformes are a family of predatory fish that includes anglerfish. The group comprises fish from numerous distinct families, including the sea toads, sea devils, goosefishes, monkfishes, and frogfishes.
Slow-moving ambush predators, anglerfish earn their name from the distinctive method they capture their prey.
A long, bony “arm” protrudes from the top of the anglerfish’s head. At the end of the arm, a fleshy protrusion serves as a bait to entice interested fish to approach the anglerfish. (Consider a fisherman catching a trout with a phony fly.)
The anglerfish attacks, engulfing the victim in its long teeth, as soon as the unaware fish gets within reach of its terrifying jaws!
Sharks are dangerous predators in the water and ocean. They feature seven gill holes on either side of the head and a cartilaginous skeleton.
Any marine creature would be terrified by just a quick peek at their fins. Elasmobranchii is the subclass of sharks, rays, and skates.
Because these anglerfish (there are over 50 varieties) resemble their environment, which are primarily coral reefs, the frogfish is very easy to overlook.
They come in pretty much every color and texture conceivable and resemble sponges or boulders coated with algae. Even some frogfish employ their camouflage to imitate poisonous sea slugs rather than to conceal themselves. No matter how different they may look, frogfish species all have a peculiar way of moving about.
Even though they can swim, the majority of them walk along their pectoral fins, which have developed into limbs that resemble arms and even have an elbow-like joint.
The eight-limbed, soft-bodied mollusks known as octopuses belong to the order Octopoda. Octopuses have three hearts, blue blood, and doughnut-shaped brains. They also have three hearts.
There are 300 distinct species of octopuses, each with unique traits. They are clever underwater creatures that are seen employing tools.
Mollusks of the clam variety are frequently used as food. Sandy, damp ocean bottoms are common places to find clams. People consume them all around the world.
The most popular kind of edible mollusc is the clam. Although there are many various kinds of clams, the hard shell clam, which may be found in a variety of colors, is the most common.
A type of aquatic creatures known as bivalves have shells. Although some bivalves exist in freshwater settings, most bivalves are marine creatures. A bivalve has a two-part shell. These can open and close thanks to a single-sided hinge.
Bivalves include creatures like clams, mussels, and oysters. Humans hunt and consume a lot of bivalves. The enormous clam is the biggest living bivalve in the world.
Bivalves are in the invertebrate class Mollusca, which also includes mollusks (spelt mollusc in British English).
The lovely star-shaped creatures known as starfish, or sea stars, have five limbs. Starfish are a group of marine organisms that come in a range of sizes, shapes, and arm counts.
There are starfish with approximately 40 arms. The Asteroidea class of echinoderms includes starfish.
The ribbon eel, also known as the leaf-nosed moray eel, inhabits Indonesian seas from East Africa to southern Japan, Australia, and French Polynesia. It is typically found snuggled into burrows along coral reefs.
As they mature, the juveniles change from their initial black and light yellow fin strip coloration to a vibrant blue and yellow pattern. These eels are referred to as “protrandic hermaphrodites,” which means they undergo several changes in sex during their lifetimes.
These marine mammals, which are found in the Arctic and Subarctic, are members of the Monodontidae family. Humans enjoy petting beluga whales because they are amiable and have a lovely appearance, especially their velvety, melon-like heads.
Beluga whales are frequently referred to as “sea canaries” because of their calming calls. They can dive for up to 25 minutes and descend up to 800 meters. They are closely related to narwhals.
Sea turtles, one of the most iconic marine animals, having existed for more than 100 million years. Because of the adaptability of their physical structure, these gentle giants have endured for such a long time.
They have a number of modifications that enable them to live in both freshwater and saltwater.
Corals are marine invertebrates that belong to the Cnidaria phylum, which is a broad class of related organisms. This category includes sea anemones and jellyfish.
For a brief time of their existence, corals are free-swimming larvae. They stop swimming after this point and adhere to a suitable surface on the ocean floor. Polyps are corals in this stage of development.
After that, the polyps will either make new larvae capable of floating freely or a duplicate of themselves that will remain affixed to the original body.
Over many years, corals can keep making duplicates of themselves. They progressively combine their hard exoskeletons, or skeletons that develop outside of the body, to form stony formations known as coral reefs as they go.
Many other marine creatures depend on coral reefs as crucial habitats.
The Spheniscidae family of birds, which includes flightless penguins, is mostly found in the southern hemisphere. Their two short legs, black and white coloring, and in certain species, orange and yellow head, neck, and breast, give them a distinctive body configuration.
One of the sea’s gnarliest-looking species is the frilled shark, Chlamydoselachus anguineus. Since the prehistoric creature’s roots date back 80 million years, it has an old appearance.
The frilled shark gets its name from the frilly shape of its gills and may reach lengths of around seven feet. Despite having the term “shark,” these creatures swim in a very eel-like, sinuous manner. They often consume their prey whole since they mostly eat squid.
Green Sea Turtle
The family Cheloniidae, which includes several species of giant sea turtles, includes green sea turtles. Green turtles, black turtles, and even Pacific green turtles are other names for green sea turtles. The largest hard-shelled sea turtles are green turtles.
These herbivorous turtles are widespread across the world. They only consume seagrass and algae, which gives them their green hue. There are only 80,000 nesting females, making them one of the endangered species.
Being a semiaquatic animal, the North American river otter spends time both in and out of the water. To shield the animal from the frequently encountered cold and rainy circumstances, its fur is waterproof.
Long guard hairs on this coat also serve as insulation.
The sea mammal dolphins. Dolphins are only aquatic creatures, despite having ancestors that were terrestrial mammals. Despite having streamlined, fish-like bodies, dolphins remain mammals and yet need to surface to breathe.
The family Delphinidae, sometimes referred to as the oceanic dolphins, is made up of the majority of dolphins. The biggest dolphin family, Delphinidae, has 30 species.
Oceanic dolphins are, as their name implies, marine mammals. The three other families of dolphins inhabit freshwater or brackish environments, which are comprised of both freshwater and saltwater.
In proportion to their size, dolphins have some of the greatest brains of any mammal. Dolphins are highly intelligent creatures that can collaborate, impart knowledge, and solve problems.
Christmas Tree Worm
The Christmas tree worm was appropriately named by scientists who discovered it near Lizard Island in the Great Barrier Reef.
The worm really lives in a tube, but the spiral “branches” represent its breathing and feeding mechanisms. The radioles, which resemble hairy appendages, cover these tree-like crowns. These are needed for breathing and grabbing food, but the Christmas tree worm can remove them if it senses danger.
Because of their canopy-shaped bodies and vivid colors, jellyfish are among the most well-known aquatic creatures. Some jellyfish have the ability to shine at night. These multi-organ creatures may be found all over the planet, and some of them are also quite dangerous.
The fact that the microscopic jellyfish Turritopsis dohrnii is eternal is one of the most intriguing things to know about jellyfishes. It has the ability to transform into a polyp, which is the first stage of life, and live forever. It develops illnesses or experiences trauma as it ages.
The huge water bird known as the pelican is a native of the Americas and certain regions of eastern Asia. They often reside close to bigger bodies of water and consume tiny amphibians, invertebrates, and fish. The pelican’s bill features a tiny notch that aids in their nearly flawless precision while catching fish.
Fish called eels have lengthy, snake-like bodies. Eels have lengthy fins that run along a large portion of their length. They move from side to side as they swim, creating waves that drive them through the water by traveling down their bodies. Eels may also swim in the other direction.
There are around 800 different types of eels. While the majority are marine creatures, some migrate to freshwater environments before returning to the ocean to reproduce.
Before they change into little eels, eels start off as tiny, transparent larvae that float in the ocean for up to three years. Elver is the name given to a young eel.
The box crab is very expert at disguising itself, much like many other water species. The crab, which often stays on the seabed, buries itself beneath the sand in this instance, only allowing its eyes to peek out from the murky depths.
The mating rituals of the box crab, which practically redefine what it means to be swept off your feet, are one of the most interesting parts of its life cycle. When a male box crab finds its mate, it grabs hold of her and drags her around the ocean floor until she sheds her shell.
Giant Manta Rays
The biggest species of rays are Giant Manta Rays, commonly referred to as Manta Rays or Oceanic Manta Rays. Typically, you may find them in tropical and subtropical regions.
These rays’ primary predators are large sharks and killer whales. Although the precise number of Giant Manta Rays is unknown because to their extensive migratory pattern, local estimates place their population between 300 and 1500. The biggest manta rays ever captured has a 9.1-meter wingspan.
One of the most numerous and diversified organisms on the world, sea anemones are also one of the least understood.
Only a small portion of this species’ anemones may be seen on our beaches. Sea anemones come in over 900 different kinds, some of which are so small they can only be seen under a microscope.
Fish having flattened bodies are called flatfish. On top of their body, both of their eyes are situated. This indicates that flatfish are asymmetrical, in contrast to other creatures.
Typically, flatfish are located on or close to the sea floor. They may blend with their environment because the tops of their bodies are often darker than the undersides.
With an eye on either side of their heads, flatfish larvae resemble other fish in appearance. Depending on the species, one eye migrates to the other side of the head as they go from the larval to the juvenile stage of their development.
The skull and jaws flatten at the same moment that they start swimming on their sides. Flatfish are key sources of protein for humans, including halibut, plaice, and flounder.