Spanish dancer’s flare, eggs attract many devoted fans

A rose is a rose is a rose — except when it’s the egg cluster of a Spanish dancer.

My recent column about that nudibranch and its roselike eggs generated some inspired email. About the lovely red or pink "flower," a reader wrote, "I have seen the same thing and it looked like someone cut chiffon rosettes off an old-fashioned dress and glued them to the reef. I couldn’t figure out what in the heck they were. Now I know! Thank you."

And thank you, Steph­a­nie, for describing so elegantly one of the world’s prettiest clutches of eggs.

Biologists call these flower look-alikes egg ribbons, and they are fastened with remarkable strength to the reef. The nudibranch might attach the eggs with a special glue, or the adhesive quality might be in the stickiness of the gelatinous egg cases. No one knows.

Also remarkable is the concentration of poison in the eggs, which contain more recycled sponge toxin than the nudibranch that laid them. In one lab experiment, researchers ground up the red eggs and fed them to creatures that eat almost anything.The offering were rejected.

Another Honolulu reader, physician and photographer Russell Gilbert, wondered how the nudibranch eggs held together, so he took a close-up picture. You can see the individual eggs (and Russell’s other excellent underwater photos) at hsalinks.com/12l4NJX.

"After taking this shot," he wrote, "I realized how the eggs were structured — embedded in sheets in some kind of gel-like material."

He’s right. Multiple eggs are enclosed in rigid, protective mucus capsules, which stick to each other to form the spiraled ribbon.

Once hatched, free-swimming larvae drift in the plankton, eating tiny plants. When a baby dancer is ready to settle down, it alights on its food, one of several species of sponges.

Depending on which sponge species they’re eating, Spanish dancers are red, pink or orange, sometimes mixed with yellow or white.

Most nudies only crawl, but Spanish dancers get their common name from their ability to swim in midwater, flexing their bodies energetically, their soft edges flaring like the skirts of a flamenco dancer. Most people who see this flamboyant dance become lifetime fans and protectors of Spanish dancers.

Nudibranchs in general are not long-lived, some for only a month. The life span of dancers is about a year.

Occasionally, they beach. A San Francisco reader wondered by email whether returning a grounded one to the water revives them or if the creatures were trying to die.

I don’t know, but since nudibranchs have no eyes, my guess is that groundings are accidents occurring when the creatures get too near the shore break.

At the shoreline I once found a live Spanish dancer larger than my hand and waded, fully clothed, to place the creature on the ocean floor. I don’t know whether the orange beauty survived, but it was worth getting wet to give it a chance.

Spanish dancers and their eggs inspire most everyone who sees them. Maybe Elton John’s tiny dancer was a nudibranch, and Gertrude Stein’s rose its eggs.

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Reach Susan Scott at www.susanscott.net.