Fire Corals: Sneaky, Painful & Masters of Disguise

What are fire corals? Well, they’re not true corals, although their talent for stinging certainly lives up to the fire part of its name. The tiny animals behind them are hydrocorals, hydroids that build calcium carbonate dwellings. They’re closer to jellyfishes than to the stony corals they sort of resemble.  THE FIRST THING TO SAY ABOUT FIRE CORALS IS A WARNING: THEY LOOK TOTALLY INNOCENT. But touching them, presumably accidently, has caused many a diver

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Seeing Sea Anemones – for Themselves

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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 Nematocysts & the Science of Sting

NEMATOCYSTS ARE OCEAN STINGERS’ SECRET WEAPONS. In fact, they are the stingers. The way in which nematocysts sting is a story of the sneaky, harpoon-like ordnance of Phylum Cnidaria – jellyfish, coral and gorgonian polyps, sea anemones, fire corals and hydroids. If you happen to touch a sea anemone, a sea plume or coral tentacles (which you shouldn’t do), you’re likely to not feel their sting. Actually, you’ve probably been stung, ineffectively. Those animals’ stingers

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