Honolulu Star-Advertiser © Susan Scott
April 12, 2010
These gusty spring tradewinds sure can make a mess. Leaves litter my lanai, my screens are clogged with grass clippings and pictures are crashing from my walls, their wires rusted clear through.
I’m not complaining, though. When the trades are on, our beaches bloom.
In the recent past, after periods of strong winds, the beaches of Kailua and Lanikai were often fouled with tangled nets and plastic pieces that lay there for weeks or months. Now, though, it seems that far less marine debris litters the sand there.
I’d like to think that the recent publicity about plastic pollution in the world’s oceans is causing less junk to be lost or dumped at sea, but I don’t know that for sure. What I do know, though, is that beachgoers now routinely pick up trash that crosses their paths.
Last week during a Kailua Beach walk, after the wind had been blowing like mad for days, I saw people collecting trash in plastic bags. The sand looked remarkably clean, so clean that it was easy to find treasures. There I found, gasping on the beach, a live sea hare.
“A what?” my sister said when I showed her the creature in my rescue aquarium. That’s a common reaction when discussing sea hares, not because they’re so rare, but because they’re hard to find. Even looking at good photos of Hawaii’s nine species, it was a strain to make out the animals against their backgrounds.
Sea hares are marine snails with only a small piece of a shell embedded in their backs. If you run a finger over the animal’s back, you can sometimes feel this shell, but it’s hard to see by just looking.
Called a remnant, this shell is useless, a scrap in the junk heap of evolution. Biologists classify sea hares between snails with shells (cowries, cone snails) and snails with no shell at all (sea slugs, also called nudibranchs).
Sea hares get their name from their resemblance to rabbits. Well, mutant rabbits. The sea hare has four sensory tentacles on its head, one pair standing upright and two pointing forward. The sea hare also has a plump, rabbit-shaped body. But don’t expect fur on this sea bunny. Its body is covered with slime.
Most of Hawaii’s sea hares are speckled and blend in with their seaweed surroundings amazingly well. Each species tends to match the marine plant it eats. Some sea hares are so well camouflaged that they’re nearly invisible, while others tuck themselves into cracks and crevices by day, only venturing out at night to eat.
Most of Hawaii’s sea hares (like the one I found) are a couple of inches long, but one species here grows to 10 inches long.
Like their nudibranch relatives, sea hares are hermaphrodites, male on one end and female on the other. This arrangement lends itself to chain mating, each individual acting as the male to the sea hare in front and the female to the sea hare behind. Sea hare egg masses look like tangled spaghetti.
All sea hares are vegetarians. The ones that eat red seaweeds secrete a pink to purple ink.
Some sea hares secrete toxins that protect them from predators. This toxin isn’t dangerous to handle, but don’t let a sea hare’s body slime get in your eyes.
Ancient Hawaiians ate the nontoxic sea hares, wrapping them in ti leaves and baking them in imu.
Thank you to all those beachgoers out there picking up trash. It makes a huge difference in the appearance of our beaches.
It also makes it easier to find stranded sea hares.