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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Akin to Brittlestars, Basket Stars Network in the Dark

Basket stars are the starfish relatives you’re least likely to see in their full glory. Key basket star fact: They do their work of unfolding their tangled arms and capturing passing prey in the dead of night.  Another: If you come across one during a night dive and stop to look at it – shining a light on it, of course – it’s going to fold right up and not quite disappear in front of

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Stars of Doom: Crown of Thorns Starfishes

Coral reefs are constantly being built up and simultaneously torn down, but Crown of Thorns Starfishes throw that equation out the window. Left to their own devices during population outbreaks, Acanthaster planci devour coral polyps and devastate reef habitats. Herewith: Crown of thorns starfish facts.  IF CROWN OF THORNS STARFISHES HAD A THEME SONG, it would be Darth Vader-type music. So destructive are these rogue echinoderms that their very name is synonymous with bad news

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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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Brittlestars: Well-Armed, Laid-Back and Full of Tricks  

If you think of brittlestars as just a variation on the familiar, pointy starfish, think again. They’re made quite differently, they act differently and they live quite a different lifestyle.  It’s all in the long, whip-like arms. BRITTLESTARS ARE MORE THAN JUST TRADITIONAL STARFISHES WITH LONG, SINUOUS ARMS AND LAID-BACK ATTITUDES. Actually, there are many differences between brittlestars and star-shaped starfishes, both in body design and behavior. In contrast to sea stars, brittlestars have flexible,

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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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The Inside Factor

HERE’S A RULE I FOLLOW ON DIVES: ALWAYS LOOK INSIDE THINGS. You can’t tell what’s you’ll find: Octopuses in holes or old tires, eels in crevices, brittlestars in vase sponges, cleaning gobies in barrel sponges, banded coral shrimps under ledges. Here’s a sharpnose puffer inside a tube sponge in Bonaire. Just hanging out, apparently. There appears to be another little fish, which I didn’t notice at the time, inside the tube at the right.  

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Bivalve Mollusks: Oysters & Scallops & Clams, Oh My!

ON THE REEF, OYSTERS, SCALLOPS, CLAMS AND MUSSELS ARE PRETTY MUCH THE INACTION FIGURES. Mostly, they just sit there. If you come close, they clam up, so to speak, until you go away. Yet, environmentally, economically and, yes, culinarily, they’re big players in the oceans and in our kitchens. Spoiler alert: The bivalve mollusks you’ll see on the reef are unlikely to be the ones seafood lovers salivate over. But, they’re likely to be more

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The Shrimp-Goby Connection: An Ocean Odd Couple

GOOGLE THIS FISH, THE SPOTTED PRAWN GOBY, and most of the posts you’ll find are for the aquarium trade. Amblyeleotris guttata appears to be a popular fish for home saltwater aquariums. Www.fishbase.org carries a listing for it, but it’s largely related to it colors, size and distribution (which is the Western Pacific from the Philippines down to the Great Barrier Reef at Australia. This photo was taken on the GBR). IT’S A SHRIMPGOBY    All

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