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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

Rapa whelks , native to Asia, have invaded the Chesapeake Bay and are raising concerns about economic and ecological impacts to the Bay region due to their shellfish diet. Scientists believe that...
Boring sponges get a bad rap. Their own name betrays them, announcing to the world that they are unexciting, ordinary and quite frankly, boring. However, if ever a misnomer existed, this is it. More...
Ochre seastars ( Pisaster ochraceus ) feed on invertebrates, such as coral and shellfish, like the mussels pictured here. The starfish forces open the shell with suction disks on the underside of its...
This male dancing fiddler crab ( Uca terpsichores ) has built a sand “hood” at the entrance to his burrow, which he hopes will attract females to his humble abode—as if that big beautiful claw of his...
Sunset? Time to glow! A biological clock triggers bioluminescence in the dinoflagellate Pyrocystis fusiformis . At dusk, cells produce the chemicals responsible for its light. Hear from marine...
Smithsonian squid expert Dr. Clyde Roper collaborated with National Geographic to attach this Crittercam to the head of a sperm whale, hoping to get footage of the whale’s favorite prey—giant squid...
Most wild seahorses (here the thorny seahorse Hippocampus histrix ) are monogamous and some species mate for life. Searching for mates can be difficult and risky since seahorses are poor swimmers,...
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...
A sea monster attacks a ship in an illustration for 20,000 Leagues Under the Sea by Jules Verne. The illustration is by publisher and artist Pierre-Jules Hetzel, who is most famous for his drawings...
A mangrove tree crab ( Aratus pisonii ) clings to a leaf near the Smithsonian Institution’s marine laboratory on Galeta Island, Panama, part of the Smithsonian Tropical Research Institute . During...
Ultraviolet light illuminates the growth rings in a cross-section of a 44-year-old deep-sea coral ( Primnoa resedaeformis ) collected off the coast of Newfoundland at about 1,300 feet (400 meters)...
Male fiddler crabs, like this one collected on Moorea, wave their enlarged claw as way of signaling to other crabs, especially during mating season. Learn more about the Island of Moorea in the...
Small amphipods, the blue bug-like creatures, can be seen here catching a ride on this enormous sea spider as it makes its way across the bottom. Many Antarctic creatures, like the dinner-plate-sized...
In 2006, this female giant squid attacked bait suspended beneath a Japanese research vessel off the coast of Japan in the Ogasawara Islands . This screenshot resulted when the research team pulled...
The Arctic comb jelly or sea nut ( Mertensia ovum ) is commonly found in the surface (top 50 meters) in cold, northern waters. Like other cydippid ctenophores, it has two tentacles fringed with...
This swimming crab ( Liocarcinus holsatus ) has a parasitic barnacle rooted in its reproductive system. This invasion cuts off all reproduction for an infected crab and can even cause a male crab to...
For a long time, scientists thought that some small tentacled fossils were early ancestors of jellyfish. But a new study has found that these ancient animals are actually related to an entirely...
This deep-sea black coral from Hawaii ( Leiopathes sp. ) is more than 4,200 years old. Black corals are named for the color of their skeletons, but the external tissues of black corals come in many...
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