Invertebrates

Animals without backbones make up a huge percentage of the ocean’s biodiversity. They aren’t just small (like pteropods) or squishy (like jellyfish); the giant squid and corals that build huge reefs are also invertebrates.

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Seaside Lichens

Horizontal bands of color represent different species of lichen that have...
Japanese scientists videotaped this female giant squid, alive, at the water's surface

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Giant Squid

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

Video of Cirrate Octopod aka Dumbo Octopus

This octopod is sometimes called a “Dumbo” octopod because its fins resemble the ears of Disney’s Dumbo the elephant. The video was recorded in 2003 on the Mid-Atlantic Ridge by the Russian manned submersible...
A bloom of moon jellies.

A Bloom of Moon Jellies

In recent years, blooms of jellyfish, such as these moon jellies ( Aurita aurita ) in the Chesapeake Bay, have become more common around the world for a number of different reasons . One...

The Amazing Horseshoe Crab

There’s a lot more to a horseshoe crab than meets the eye. They are not even crabs and are actually more closely related to spiders and scorpions. They don’t have teeth or jaws, and...
Sea otters floating on the surface of the ocean.

Not Just Another Fuzzy Face

A raft of sea otters grooming and resting after foraging. Credit: © Elise Newman Montanino Who hasn’t grinned at the sight of a sea otter floating on its back while grooming itself? No doubt...

Anemone Feeding Time

Anemones are known for serving as homes for Nemo and countless other small fish and invertebrates. But these Cnidarians (in the same phylum as jellyfish and same class as corals ) have a long...
Two nautiluses in the open ocean off the coast of Palau.

A Couple of Nautiluses

These two nautiluses ( Nautilus belauensis ) are pictured off the coast of Palau in the Pacific Ocean. There are six living species of nautilus who live in chambered shells. As they get bigger,...
Venomous Box Jelly from South Carolina

Pinning Down the Jellyfish

Credit: Bastian Bentlage 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...
Coral Spawning by Moonlight

A Tale of Sex and Stress in the Ocean

A coral has just spawned. Each of the hundreds of polyps releases a small pink bundle of sperm and eggs. Credit: Raphael Williams Welcome to Citizens of the Sea , a new blog series...
Horseshoe Crab in Stage Harbor, Massachusetts

This Flu Season, Thank a Horseshoe Crab

A small horseshoe crab rests on seaweed in Stage Harbor, Massachusetts. Credit: © Luke Robinson (Creative Commons via Flickr) Fever. Aching muscles. Coughing. Sniffling. It’s flu season . Have you had your shot? If...

Hydrothermal Vent Creatures

Travel to a world of perpetual night--the deep ocean hydrothermal vents near the Galapagos Rift where life thrives around superheated water spewing from deep inside the Earth. Discovered only in 1977, hydrothermal vents are...
An underwater photo of coral recovering from a bleaching event.

A Pleasant Surprise: The Recovery of Bleached Panamanian Corals

These corals are still in recovery after a mass bleaching in Panama, in the summer of 2010. You can see some bleaching on the tops, but the sides are looking good. Credit: Amanda Feuerstein...
Common cuttlefish

So You Think You're Smarter Than a Cephalopod?

Like other cephalopods, the common cuttlefish ( Sepia officials Linnaeus, 1758) possesses serious brain power. Credit: Hans Hillewaert, WoRMS for SMEBD The blanket octopus can rip a poisonous tentacle from a Portuguese man-o-war and...
A zoomed-in image of the crown-of-thorns sea star.

A Plague of Sea Stars

Scientists have been studying why populations of crown-of-thorns sea stars ( Acanthaster planci ) have mushroomed in recent decades. Coral reefs can suffer when the sea star's numbers explode; the echinoderm has a healthy...

The Dumbo Octopus: An Underwater Dance

This short video takes you two hundred miles off the coast of Oregon and some 6,600 feet below the water's surface to observe the Dumbo octopus ( Grimpoteuthis bathynectes ). Little is known about...
Juvenile plane-head filefish

A World Adrift: Life in the Sargassum

The open ocean is surprisingly barren to the naked eye. Every now and again you will encounter a school of fish and their attendant predators, but most of the life that you find is...

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