Ocean Watch
By Susan Scott
Monday, August 2, 1999
WHILE walking through the Ala Wai Boat Harbor last week, my visiting niece spotted some trash floating in a corner. Ala Wai has
problems but
also surprises"This water is really dirty," she said, wrinkling her nose.
It wasn't, actually. Beneath the plastic bags and Styrofoam cups, the water was crystal clear. I pointed this out and as we approached the outer harbor, the trash disappeared, revealing some of the most beautiful and interesting marine life Hawaii has to offer.
The much-maligned Ala Wai has its problems, but it's not all bad. Besides regularly spotting some of my favorite species, I continue to see animals there I have never seen before.
Once, while walking on the sidewalk near the middle harbor, something big and shimmering caught my eye. I squinted into the water and to my astonishment saw several thread-finned jacks, also called ulua kihikihi, go cruising by.
These have to be some of the most beautiful fish in Hawaii. Their diamond-shaped, silvery bodies are adorned with long filaments streaming from dorsal and anal fins. Both bodies and filaments flash iridescent colors in the sunshine, a phenomenon I was privileged to see that one time only.
Another time, in the innermost part of the harbor, I saw an eagle ray gliding through the garbage like a blue angel.
LAST week, I had one of my best ever Ala Wai moments. My sister and her son went snorkeling along the outermost pier of the harbor to try out new masks and snorkels. They came back reporting they had found something weird and wonderful. Their description sounded like a colorful hamburger. I was baffled.
"What was it?" I asked my husband, an experienced snorkeler who had been with them.
He shrugged.
"I have no idea."
"None?"
"No. It was really unusual."
The next morning, we went back to find the thing. Of course, it was gone. I had imagined some kind of sponge or tunicate, but no, apparently this creature could walk.
I gave up and went back to the boat but soon heard a call from the water, "Get a bucket!"
It was the strange animal, indeed looking like a small hamburger. On its top was a concave shell that didn't quite fit, like a too-small hat. The middle part of the animal was yellowish, squishy and covered with firm blue bumps. On the bottom was an orange, rubbery foot that oozed slime when you touched it.
We stared at the creature, then everyone stared at me, waiting for a pronouncement. But I had no idea what the thing was either.
THERE was only one thing to do: Take it to the Waikiki Aquarium. We piled into the car and soon aquarium director Bruce Carlson was peering into our bucket.
"It's a mollusk," he said. "An opistobranch of some kind. Wait here."
Bruce returned with his books and soon identified it as an umbrella slug.
Umbrella slugs are an odd type of sea slug. They have gills only on one side, a shell that doesn't cover the body, and a "face' on the side bearing two eyes, two tentacles and a noselike penis just above the mouth.
These sponge-eating slugs have a wide range throughout the tropical waters of the Indian, Pacific and Atlantic oceans but are rare in Hawaii. This was the first one Bruce had seen here and the first time I had even heard of such a creature.
Finding that umbrella slug was fun for all of us, proving once again that Hawaii's waters hold great surprises -- even in the Ala Wai Boat Harbor.
Marine science writer Susan Scott's Ocean Watch column
appears Mondays in the Star-Bulletin. Contact her at honu@aloha.net.
