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Open-ocean animals

The open sea and the deep: whales, dolphins, sharks, tuna, swordfish and squid, and the strange animals of deep water such as anglerfish, oarfish, blobfish and the coelacanth.

Remember in a game that whales and dolphins are mammals, and that on this site flippers don't count as legs.

67 animals, A to Z.

• 🐾AlbatrossLarge seabirds of the Southern Ocean and North Pacific, among the biggest flying birds.
• 🐟AnchovyMore than 140 species of small, silvery-green schooling fish of the Atlantic, Indian and Pacific Oceans, the Mediterranean and the Black Sea; a few live in South American rivers.
• 🐾AnglerfishFish that lure prey with a modified fin ray on the head, tipped with a lure that glows in some species.
• 🐾BarnacleAbout 2,100 species of marine crustaceans related to crabs and lobsters.
• 🐟BarracudaAbout 26 species of long, silvery predatory fish with fang-like teeth and an underbite, found in tropical and subtropical oceans worldwide, near the surface, coral reefs and seagrass.
• 🐾BelugaAn all-white whale of the Arctic and sub-Arctic, the narwhal’s closest relative.
• 🐾BlobfishThe smooth-head blobfish, a deep-sea fish of the waters off Australia, Tasmania and New Zealand, usually under 30 cm long.
• 🐋Blue whaleA baleen whale, the largest animal known to have ever existed: up to 30 m long and 200 tonnes.
• 🐠ClownfishSmall reef fish of the warm Indo-Pacific that live among sea anemones, sheltered by the stinging tentacles.
• 🐟CodThe Atlantic cod is a large, brown or green spotted fish of the North Atlantic, one of the most widely eaten fish in the world.
• 🐾CoelacanthA lobe-finned fish more closely related to lungfish and land vertebrates than to most fish.
• 🐾CoralSea animals that live as colonies of many identical polyps, each a few millimetres across with a ring of stinging tentacles around its mouth.
• 🦀CrabArmoured crustaceans with the tail tucked under the body, able to run sideways.
• 🐾CuttlefishMarine cephalopods with W-shaped pupils, eight arms and two tentacles, and an internal shell, the cuttlebone, that controls buoyancy.
• 🐬DolphinAround 40 species of toothed whale, from the 1.7 m Maui’s dolphin to the orca, the largest at 9.5 m.
• 🐾DugongA seagrass-eating marine mammal of the Indo-West Pacific, the manatee’s relative and the only living member of its family.
• 🐍EelAbout 1,000 species of long, snake-like fish, mostly marine.
• 🐾HagfishEel-shaped, jawless sea fish, usually about 50 cm long and dull pink to blue-grey, with loose skin and no true fins.
• 🐟HalibutThree species of large flatfish of the North Atlantic, North Pacific and Arctic: the Atlantic, Pacific and Greenland halibut.
• 🦀Hermit crabAbout 800 species of crustaceans that protect their soft abdomen in empty snail shells.
• 🐟HerringOily forage fish that travel in huge schools through the shallow, temperate waters of the North Atlantic and North Pacific, including the Baltic Sea.
• 🐋Humpback whaleA baleen whale with very long flippers and knobbly bumps on its head, famous for breaching and for the long, complex songs males sing.
• 🪼JellyfishSoft, free-swimming sea animals with a bell-shaped body and stinging tentacles.
• 🐾KrillSmall, shrimp-like marine crustaceans found in every ocean, near the bottom of the food chain.
• 🦞LobsterLarge marine crustaceans with long bodies, muscular tails and big front claws, highly prized as seafood.
• 🐾Manta rayThree species of huge rays of warm seas, with triangular fins and horn-shaped flaps by the mouth.
• 🐟MarlinLarge ocean predators with a spear-like bill and a long, rigid dorsal fin.
• 🐾Moray eelAbout 200 species of eels found worldwide, almost all marine.
• 🐾NarwhalA toothed whale of the Arctic, closely related to the beluga.
• 🐾NautilusNine species of shelled cephalopods from the Indo-Pacific, the last living members of an ancient group.
• 🐾NudibranchAbout 3,000 species of soft-bodied sea slugs that shed their shell after the larval stage, many of them in startling colours.
• 🐾OarfishThree species of very long, ribbon-shaped silver fish with a red crest and a dorsal fin running the whole length of the body.
• 🐙OctopusEight-armed molluscs, about 300 species, with three hearts and copper-based blood.
• 🐋OrcaThe largest member of the dolphin family, black above and white below with white eye patches.
• 🐾OysterSaltwater bivalve molluscs with rough, often irregular shells.
• 🐾Pelican eelA deep-sea eel of temperate and tropical oceans, living 500–3,000 m down, with a loosely hinged mouth much larger than its body.
• 🐧PenguinFlightless seabirds of the Southern Hemisphere with flippers for swimming.
• 🐾PorpoiseEight species of small, dolphin-like toothed whales, more closely related to narwhals and belugas than to dolphins.
• 🐡PufferfishFish that puff up into a ball when threatened.
• 🐾PuffinThe Atlantic puffin is a small seabird of the auk family with a big red-and-black beak.
• 🐟SailfishA blue-grey billfish of the open ocean, named for the huge dorsal fin that runs almost the whole length of its back.
• 🐟SalmonFish that hatch in rivers, go to sea to grow, then return to fresh water to spawn, usually in the stream where they hatched.
• 🐾ScallopSea bivalves found in every ocean but never in fresh water.
• 🐾Sea anemonePredatory relatives of corals and jellyfish, named after the anemone flower.
• 🐾Sea cucumberAbout 1,786 species of soft, leathery, cucumber-shaped echinoderms living on the sea floor worldwide.
• 🦭Sea lionEared seals with external ear flaps, long front flippers and the ability to walk on all fours.
• 🐾Sea otterThe heaviest member of the weasel family, and one of the few mammals that use tools: it cracks shellfish open with rocks.
• 🐾Sea spongeSimple animals fixed to the seabed, with bodies full of pores and channels.
• 🐢Sea turtleSeven species of ocean-going turtles, including the green, loggerhead, hawksbill and leatherback.
• 🐾Sea urchinAbout 950 species of spiny, globe-shaped echinoderms living on the seabed of every ocean.
• 🐾SeadragonThe leafy seadragon, a relative of the seahorse covered in leaf-like lobes of skin that make it look like floating seaweed.
• 🐠SeahorseSmall bony fish, 47 species, named for their horse-like head and neck.
• 🦭SealFlippered marine mammals: the true seals, the sea lions and fur seals, and the walrus, 34 species in all.
• 🦈SharkCartilaginous fish with five to seven gill slits on each side and rows of replaceable teeth.
• 🦐ShrimpCrustaceans with long bodies, long antennae and thin legs, which swim forward with paddles under the tail and flick backwards to escape.
• 🐌SnailA gastropod with a coiled shell big enough to pull itself into.
• 🐋Sperm whaleThe largest toothed whale and the largest toothed predator.
• 🦑SquidFast-swimming molluscs with large eyes, eight arms and two long tentacles.
• 🐾StarfishStar-shaped echinoderms, not fish, with about 1,900 species on the seabed of every ocean.
• 🐾StingrayAbout 220 species of flat, cartilaginous fish with a venomous barbed stinger on the tail.
• 🐟SwordfishA large, migratory predatory fish with a long, flat, pointed bill.
• 🐾TardigradeAbout 1,500 species of plump, eight-legged micro-animals, usually about 0.5 mm long, also called water bears or moss piglets.
• 🐟TunaFifteen species of fast, streamlined ocean predators in the mackerel family.
• 🐢TurtleShelled reptiles, about 360 species, including land-living tortoises, freshwater terrapins and sea turtles.
• 🐾VaquitaThe smallest of all whales, dolphins and porpoises, found only in the far north of the Gulf of California in Mexico.
• 🦭WalrusA huge Arctic pinniped with long ivory tusks, bristly whiskers and a nearly hairless body.
• 🐳WhaleOcean mammals that breathe air and feed their young on milk, including the blue whale, the largest animal that has ever lived.

How each answer is decided: How we answer. Every animal, in one list: All animals.