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Depending on whom you talk to, jellyfish are either fascinating, a nuisance, a toxic menace, or some combination of the above. Jellyfish plop into the media spotlight when their presence causes beach closures, or...
The ocean is home to a phenomenal diversity of marine organisms. They have...
What reef animal comes in a rainbow of crazy colors, can throw out its stomach...
This summer, many of you have likely enjoyed feasting on crabs, be they blue,...

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The sea hare gets its common name from its equivalent of nose and tongue—external sensory organs for smell and taste called rhinophores—which look like bunny ears. The sea hare, however, doesn't hop like a rabbit: it is a sea...
“Upon returning from the reef after a night dive, I swam toward a bright...
This ctenophore (a stingless jellyfish-like animal) is native to the east...

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Giant squid live up to their name: the largest giant squid ever recorded by scientists was almost 43 feet (13 meters) long,...

The Ocean Blog

Many jellyfish in the class Hydrozoa, such as this hydromedusa Aglantha digitale , are transparent and easily overlooked. Learn more about hydrozoan jellies and other jellyfish , and see more...
Thalassinidean shrimp ( Thalassinidea ) build complex burrows deep in the mud. More about mangroves ecosystem can be found in our Mangroves featured story .
Squids come in a wide range of sizes but despite differences in size and shape, all work basically the same way inside. More about the giant squid can be found in the Giant Squid section .
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...
Zombie worms ( Osedax roseus ) eat away at the bones of a dead whale that has fallen to the seafloor in Sagami Bay, Japan. These bizarre worms rely on whale bones for energy and are what scientists...
Ocean creatures may not sing carols and go ice skating, but some celebrate the winter holidays all year round! So turn on the “Jingle Shell Rock” and celebrate with these intriguing ocean animals.
Bivalves brought up in a box corer from the deep Arctic seafloor.
When this tusk shell was brought up from the deep reef, it was a surprise when a hermit crab poked out! Notice the hermit crab's large claw that it can use to tightly cover the shell opening when it...
In 2010, scientists from NOAA and Woods Hole Oceanographic Institute found dead and damaged deep-sea corals in the Gulf of Mexico, potentially affected by the Deepwater Horizon oil spill . These...
This tan urchin, Conolampas sigsbei , is one of only two known deep-sea urchins that cover their tops with small rocks and shells. Many shallow species cover themselves for reasons that have been...
Dead man’s fingers ( Alcyonium digitatum ) are soft corals named for their appendage-like appearance when thrown ashore by storms. The finger-like clumps of coral polyps come in various shades of...
A blue cod and sea pens , a unique type of cnidarian , speckle the seafloor in New Zealand's Fiordland region.You can see more beautiful underwater photos from Brian Skerry in his image gallery .
Two California market squids ( Loligo opalescens ) mate in the waters off of California's Channel Islands. While spawning, the male's arms blush red as he embraces the female, a warning to other...
Some of the most otherworldly animals—like those straight from a science fiction story—can be seen in the open ocean at night. By drifting in the blackwater in a scuba suit just under the surface,...
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...
This photo shows just a small part of the cephalopod collection at the Smithsonian's National Museum of Natural History. Shown here is Dr. Clyde Roper , a zoologist and squid expert. More about the...
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...
This beautiful larval (baby) octopus was collected by scientists from the University of Miami during a research cruise in the Straits of Florida, a narrow channel between the Atlantic and the Gulf of...
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