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What reef animal comes in a rainbow of crazy colors, can throw out its stomach to immobilize predators, then creep away and regrow a brand-new stomach? It’s the sea cucumber, prized as a gastronomic...
This summer, many of you have likely enjoyed feasting on crabs, be they blue,...
About 100 million years ago , during the heyday of the dinosaurs, reefs were...
Zombie worms don’t crave brains: instead they seek bones. The 1 to 3 inch (2 to...

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“Upon returning from the reef after a night dive, I swam toward a bright reflection and came eye-to-eye with this beautiful, curious squid," said Charles Viggers, a Nature's Best photographer. Squids have organs in their skin...
This ctenophore (a stingless jellyfish-like animal) is native to the east...
This nudibranch has a few tricks up its sleeve: it steals jellyfish...

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Sample the surprising diversity of deep-sea corals. See some of the ways they differ in color, shape, and size. Explore more...

The Ocean Blog

Found in Arctic waters, this rare deep-water species of larvacean , Oikopleura gorskyi , eats by filtering particles from the seawater it drifts through. Larvaceans build 'houses' around themselves...
The Census of Marine Life - a ten-year effort by scientists from around the world to answer the age-old question, “What lives in the sea?” It was an international effort to asses the diversity,...
A rockfish finds refuge in a deep-sea coral—a red tree coral of the Primnoidae family in the Olympic Coast National Marine Sanctuary. Learn more about deep-sea coral reef ecosystems in our Deep-sea...
Glowing photophores are visible on this midwater squid ( Abralia veranyi ) viewed from below at low light levels. We think of light as a way to see in the dark. But many species use it to help them...
Come one, come all! See the amazing, the astonishing, half-animal, half-plant! Journey to Tampa Bay, Florida, where scientist Skip Pierce and one of his students first made a remarkable discovery...
Seahorses range in size—from as small as a pine nut to as large as a banana. The largest seahorse species (pictured here) is Hippocampus abdominalis , or the big-bellied seahorse, which can reach...
Another common species of sargassum shrimp, Leander tenuicornis (Palaemonidae), can be spotted by its long transparent claws or "chelae". Very similar shrimp are found in near shore habitats all...
An adult giant squid struggles for survival in an encounter with a sperm whale - its only known predator. The whale will probably overpower and eat the squid. More about the giant squid can be found...
The “Hyperbolic Crochet Coral Reef,” a unique exhibition and thought-provoking fusion of science, conservation, mathematics, and art, is on display in Washington, D.C., at the Smithsonian’s National...
This bivalve mollusk is native to the Caspian Sea, lagoons of the Black Sea, and their inflowing rivers. It lives in fresh and brackish water and cannot tolerate full seawater. In the 18th and 19th...
Isopods (small, shrimp-like animals) like this one ( Gnathia aureusmaculosa ) are the mosquitoes of the sea, sucking the blood of fish while they sleep. Find out more in " No Fouling Around " from...
Atolla tenella , a midwater scyphomedusa , as seen under a microscope. View the “Under Arctic Ice” photo essay to learn more.
Light refracts off the comb-rows of the Mertensia ovum , a ctenophore , producing stripes of rainbow colors . The jelly eats copepods and small crustaceans that become stuck to its sticky tentacles...
This common octopus ( Octopus vulgaris ) doesn't have a jetpack to help him zoom through the water, but he's got something pretty close: a siphon that shoots water. (It's the little orange/yellow cup...
Seahorses are not just tropical creatures. They can be found in colder waters like those found off New Zealand, Argentina, Eastern Canada, and the UK. This long-snouted seahorse ( Hippocampus...
The blue lined octopus may be small, growing to at most 15 cm, but it can be deadly: its venom can cause breathing failure in humans as well as other animals. Turtles can accidentally consume the...
This close-up photo shows the tough, serrated ring around the opening of a giant squid sucker. The ring is made of chitin—the same material that’s in your fingernails. Using suction, the sucker...
This brilliant red octopus ( Benthoctopus sp. ) was photographed at more than 8,800 feet (about 2,700 meters) in Alaminos Canyon in the Gulf of Mexico. See more photos of wild creatures encountered...
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