A slideshow of the newest features on Poseidon’s Web – Explain the Reef!

About Polychaetes: Marine Worms to You and Me

Worms may be fairly low on most reef visitors’ bucket lists but they’re super-important members of the reef environment. Overwhelmingly Polychaetes – that is, segmented worms lined with little limb-like appendages – they’re key prey in the marine food web and themselves important consumers of organic debris in the sediments.   FOR OUR PURPOSES – THAT IS, FOR SEEING THE REEF – marine worms come in three categories: The flashy tube worms we see all the time –

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How Do Flying Fishes “Fly?” Well, Actually, They Glide.

Why do flying fishes fly? To escape predators, to flee from surprises like boat engines next them, perhaps to entertain you during the ride to a dive site. In any event, they earn their names by propelling themselves out of the water and gliding for long distances on broad pectoral fins. Torpedo-shaped and silvery, sometimes with markings in subdued colors, they’re not especially exotic visually. But they’re impressive both underwater and in the air. YOU’RE

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Do Sea Urchins Sting? No, But They Hurt All the Same

What are sea urchins? Members of Class Echinoidea, they’re distant cousins of starfishes that boast imposing defenses and bad reputations. Do sea urchins sting? Not really. It’s more that they impale. But, if you don’t bother them, these oceanic pincushions won’t bother you. The trick is in not accidentally bothering them. RATHER THAN APPRECIATING SEA URCHINS, MOST PEOPLE FLEE FROM THEM, CAREFULLY. After all, the likely result of interacting with these oceanic pincushions while doing

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All Arms, All the Time: Feather Star Facts

UNLIKELY ANIMALS THEY MAY SEEM TO OUR EYES, but feather stars are full-fledged members of the animal kingdom. Here’s a key feather star fact: They may seem to be fixed in place in their perches on coral heads or sponges  or sea rods, but these crinoid creatures eat, reproduce and move like other animals. As a bonus, they’re often beautiful and compelling.  TECHNICALLY, FEATHER STARS HAVE ARMS JUST LIKE THEIR STARFISH AND BRITTLESTAR COUSINS. At

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Fevers, Shivers & Risks: Marine Animal Group Names

We’re all likely familiar with the terms “murder” of crows and “pride” of lions for assemblages of those animals. But marine animals groups have names, too, some familiar, some strange and some… really strange. As in, a “fluther” of jellyfish, a “risk” of lobsters and a “turmoil” of porpoises.  There’s not any point to any of this but still I felt impelled to produce a list, from fishes to sea birds, sharks to pelicans, after

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These Jellyfish Sting with “Mucus Grenades”

Researchers have discovered that seemingly benign upside-down jellyfish utilize a unique, previously unrecognized weapon to capture prey: “Stinging mucus grenades.” It explains the “stinging water” pain that divers, snorkelers and waders sometimes experience without coming into actual contact with the jellies. Upside-down jellyfish have been recognized for some 200 years, but nobody knew this until now. TO ALL APPEARANCES, UPSIDE-DOWN JELLYFISH LIKE CASSIOPEA XAMACHANA spend their days resting on the shallow bottoms of reefs and

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What Are Sponges? Maybe the Future of the Reef.

What are sponges? They’re animals, perhaps animals that stretch our conception of the term, but animals for sure. It’s easy to dismiss them as just backdrop scenery to more exotic stuff on the reef. But ocean sponges come in amazing shapes and colors, chug along with body features unique in the animal kingdom and perform important reef-related roles.  Sponges were among the earliest arrivals in the ocean. And, if corals disappear, sponges may be the

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Seeking Fish, Patrolling Albatrosses Join the Cops

In an innovative experiment to help find commercial fishing vessels poaching in restricted waters, scientists have attached tiny radar detectors to high-soaring albatrosses, renowned flyers known for their attraction to ships at sea. Patrolling albatrosses revealed that about a third of ships in the Southern Indian Ocean were seeking to avoid detection. TWO IMMUTABLE FACTS: 1) IF THERE’S FOOD AROUND, ANIMALS WILL SHOW UP FOR AN EASY MEAL. 2) There are always going to be

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True Soft Corals: Beautiful, with an Identity Problem

True soft corals are among the most beautiful gems of the reef, yet they’re difficult to get a handle on etymologically. People insist on calling other stuff, like sea fans and mushroom corals, “soft corals.” Species in Family Nephtheidae deserve to be appreciated and understood by themselves.  TRUE SOFT CORALS ARE BEAUTEOUS TO BEHOLD AND DIFFICULT TO DEFINE. They’re beautiful in their delicate multi-branched structures, feathery clusters of polyps and striking pastel reds, yellows, blues,

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Seahorse Anatomy: Differences Way Beyond “Cute”

Seahorses are at once weird and wonderful, exotic and underwhelming and unique among bony fishes. Underneath their obvious horsey-head charm, seahorse anatomy is really, really different from other fishes. THE MOST OBVIOUS THING ABOUT SEAHORSES IS THEIR BODY DESIGN – an upright torso connecting a horse-shaped head and a monkey-like tail. They’re bony fishes, but pretty much the only bony fish that swims upright. When they swim. If searching for them carries an air of

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