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The Ocean Blog

Atolla tenella , a midwater scyphomedusa , as seen under a microscope. View the “Under Arctic Ice” photo essay to learn more.
"Inside the Open Ocean: Blue Water Diving" produced by Woods Hole Oceanographic Institution (WHOI) , describes a specialized diving technique that lets biologists study the ocean's most fragile...
In this episode of the Podcast of Life , learn how three fiery, painful stings during an early morning swim in Hawaii changed the life of researcher Angel Yanagihara. Once the young biochemist had...
How long have jellyfish lived in the ocean? This jellyfish fossil is from the Cambrian period, more than 500 million years ago. It was found buried in Utah —an area that used to be underwater,...
A still from The Changing Sea , part of the 19th Annual Environmental Film Festival in the Nation's Capital.
Many expeditions in the Arctic reveal new species, such as this jellyfi sh Bathykorus bouilloni , which, strangely, has only four tentacles! Dr. Kevin Raskoff from California State University,...
Seagrasses don't just provide shelter for free-swimming animals, but also are a habitat for non-moving organisms, such as this sea anemone. Sessile animals attached to blades are called epibionts,...
Alien-looking creatures like this deep-red jellyfish ( Crossota norvegica ) swim in the Arctic Sea. Learn more about Arctic sea life in our Under the Arctic Ice story, or at the home page for the...
The Baltic is a brackish sea, a unique combination of freshwater from rivers in the surrounding countries and salt water from the ocean. The low salinity levels are one of the factors that determine...
Giant anemone. More about mangrove ecosystems can be found in the Mangroves section .
A still from Journey of the Universe , part of the 19th Annual Environmental Film Festival in the Nation's Capital.
These large jellyfish ( Chrysaora fuscescens ) are most commonly found along the coasts of California and Oregon. (They're also popular in the displays of public aquaria.) Their bells can grow to a...
If you don’t like purple, you can look for this anemone (Condylactis sp.) in green. It comes in different colors and brightens a variety of Caribbean reef habitats, from lagoons to deeper waters.
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...
A cnidarian brought up from the Arctic seafloor more than 2000 meters (6562 feet) deep.
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 .
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