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Not all slugs (snails without shells) are slimy brown pests found in your backyard garden. In the ocean they come in a huge variety of colors — some match the background and are hard to spot, but...
The ROV Hyper Dolphin caught this deep-sea jelly (Atolla wyvillei) on film east of Izu-Oshina Island, Japan. When attacked, it uses bioluminescence to "scream" for help—an amazing light show known as...
You may have seen the sparkle of fireflies on a summer’s night. The fireflies produce light through a chemical reaction in their glowing abdomens, a process known as bioluminescence. But did you know...
When most people think of catfish, they think of a freshwater fish. But the striped eel catfish ( Plotosus lineatus ) is found in marine systems including coral reefs, estuaries, tide pools and other...
Is that fruit swimming in the ocean? Well it may look like fruit, but it's actually a pineapplefish ( Cleidopus gloriamaris ). Like the hard outer part of a pineapple, this fish also has an outer...
This summer, many of you have likely enjoyed feasting on crabs, be they blue, stone, or Dungeness, and a special treat will have been the big, easy morsels of claw meat. The size of this muscle is...
Beluga whales are naturally vocal animals. They are often called “ canaries of the sea ” thanks to their wide repertoire of sounds such as whistles, squeals, moos, chirps, and clicks. Some...
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...
When hoping to discover a pearl, looking inside one of the oysters you slurp may not be the best plan. Food oysters in the family Ostreidae are able to produce pearls, however these tend to be small...
These beautiful mandarinfish ( Synchiropus splendidus ) are covered in bright blue, red, yellow and orange waves. What they lack, however, are traditional fish scales. They live in western Pacific...
“It’s a little appreciated fact that most of the animals in our ocean make light,” says Edie Widder, biologist and deep sea explorer at ORCA. In this TED talk, she shows incredible film and photos...
A humboldt squid ( Dosidicus gigas )—also known as the jumbo squid—releases a cloud of ink at night in Mexico's Sea of Cortez. These large, carnivorous squids can reach more than 5 feet in length and...
Two bright orange anemonefish ( Amphiprion ocellaris ) poke their heads between anemone tentacles. Anemonefish are able to swim amongst the stinging tentacles without getting stung — but no one knows...
This bait ball shows how small fish can react when larger predators are near by gathering tightly together in a ball-like formation that exposes the least number of fish. Fish species found in the...
This crab ( Neolithodes sp. ) was collected on a NOAA/MAR-ECO cruise to the Mid-Atlantic Ridge in the summer of 2009. Its red color provides camouflage and protection from predators. Red wavelengths...
An octopus shoots ink in defense as it swims away from a scuba diver.
Nudibranchs are a kind of sea slug, and their 3000 species are found from the poles to the tropics in both shallow and deep water. Though they often only reach two centimeters in length, they are...
Stinging cells (nematocysts) line the tentacles of this moon jelly ( Aurelia aurita ). Upon contact with prey or a predator, a venom-laden harpoon shoots out to stun or kill. Read more about...
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