Highlights from the Poseidon’s Web archives.
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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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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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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Walking sharks are only a small piece of our planet’s shark universe, but they’re remarkable for their ability to propel themselves along the seafloor using bodies and fins. And, actually, on land – literally fishes out of water. New walking shark research by an international team of scientists has found that, in terms of evolution, they are the most recent group of sharks to arrive on the scene. DESPITE A COMMON MISCONCEPTION, only a small number
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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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SEA ANEMONES ARE PROBABLY BETTER KNOWN FOR THE COMPANY THEY KEEP than for their unassuming, hard-working selves. On Caribbean dives, I rarely pass by one without checking it out for exotic little cleaner shrimps that might be in residence. If there aren’t any, I’m disappointed and move on. In the Pacific, of course, you hardly have to check them out to be aware of their frenetic, constantly on-the-move, high-visibility companions – clowns and other anemonefishes.
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IF IT LOOKS LIKE A PIG AND IT WALKS LIKE A PIG AND IT’S UNDERWATER, THEN IT MIGHT BE A…SEA CUCUMBER. Specifically, a member of the genus Scotoplanes. Or, to its multitudinous fans worldwide, a sea pig. Whereas most of us are used to seeing sea cucumbers that actually more or less resemble cucumbers in body shape, Scotoplanes species like S. globosa really do remind people of pigs. Plump, pink and sporting rather porky “legs,”
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BLACK CORALS ARE PROBABLY BEST KNOWN AS SHINY, JET BLACK JEWELRY. As living coral in their underwater habitats, they’re actually unlikely to be black. So what does black coral look like, actually? They’re most likely to be found in shades of soft reds, greens, yellows and other colors. They’re not stony corals – they grow in complex linear structures resembling trees, bushes or sea fans. The “black” part is the protein-based chitin that comprises the
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WHAT’S THE DIFFERENCE BETWEEN BALLOONFISH AND PORCUPINEFISH? They’re both unobtrusive, usually little guys with an ability to inflate into spiny basketball-shapes when disturbed. It’s a defensive response to threats. And, divers are often confused as to which is which. First of all, when you see picture of them, they’re often inflated like stuffed pincushions. In fact, like this…. But the truth is that recreational divers who are minding their manners are unlikely to see them
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WHEN PEOPLE SEE THE WORD “CORAL,” it very likely brings to mind the great mounds of star and brain corals that stand out on the reefs. In fact, “corals” include many organisms beyond the familiar stony formations, all built on similar, tiny, coral polyps. “Coral” itself is a flexible word. It applies to the coral exoskeletons that we see as the visible shells of hard corals, to the polyp animals that live within those exoskeletons
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