Monthly Archives: November 2014

Collector urchins munch up fast-growing invasive algae

Published November 24, 2014 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2014 Susan Scott

A collector urchin is dotted with items it has picked up. ©2014 Susan Scott

Who knew that a poky marine animal the size of a snow globe could do such a stellar job of fighting aliens?

The plodding heroes are collector urchins, a native species the state has been raising by the thousands and releasing in Kane­ohe Bay. There the sea urchins work like slow-motion Pac-Men, gobbling up weeds, the weeds in this case being three seaweed species gone to the dark side.

But we can’t blame the seaweeds. Industrial researchers brought the edible red algae, native to the Philippines and Malaysia, to Coconut Island in 1974 to raise for its rich carra­geenan content.

A nearly endless number of foods and household products contain carrageenan, a thickener. On the long list are toothpaste, ice cream, beer, shampoo, diet soda, pet food, milk, jam and medicines.

Red algae aquaculture failed as a business, but the hardy seaweeds escaped and went wild. One species can double in size in 15 to 30 days, growing to 6 feet tall with a 1-inch-diameter base and sprawling, finger-thick branches. The dense stalks shield the bay’s native corals from the sunlight they need to live.

To keep the seaweeds from destroying Kane­ohe Bay’s reefs, workers remove bulk weeds with a machine called the Super Sucker. Because bits of broken-off seaweed tips can quickly grow into mats, tens of thousands of algae-eating collector urchins are being released in the bay.

As vacuum cleaners of the reef, the urchins use hundreds of suction-cup feet to amble around, day and night, eating seaweed with a circle of five teeth at the center of their undersides. Following a Super Sucker session, the black whiskery creatures hoover their little hearts out.

Collector urchins are not the needle-sharp, long-spined sea urchins we call wana. Collectors, called hawae maoli in Hawaiian, are endearing little creatures with a touchable surface similar to a stiff hairbrush.

I have dozens of pictures of collector urchins because they wear silly hats, piling everything from rocks to plastic spoons to skeletons of their own babies on top of their round shells. Biologists think the animals’ hodgepodge collections act as shields from bright sun and might also disguise an urchin from fish and octopus predators. Whatever the reason, the results are adorable.

Our spheroid storm troopers might not have light sabers to battle plant aliens, but they’re making impressive progress with teeth and tube feet. May the Force be with them.

mandarinfish


Marine biologist Susan Scott writes the newspaper column, “Ocean
Watch”, for the Honolulu Star-Advertiser, www.staradvertiser.com

©2014 Susan Scott

Waters off Palau are home to treasure trove of sea life

Published November 17, 2014 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2014 Susan Scott

A mandarinfish in Palau. ©2014 Susan Scott

On the last day of my week in Palau, I asked five snorkeling companions to name their favorite part of the trip. The fact that we were evenly divided in our choices is testament to the wide variety of stunning marine life in this island nation of Micronesia. We were two for Ulong Channel, two for Jellyfish Lake and two for mandarinfish.

Ulong is a long, narrow island in western Palau, and the channel that runs near it has strong currents that nourish an astonishing number of coral species. Every shade of blue, pink, yellow, green and brown shaped like fingers, tables, bubbles, fans and flowers dazzled us as we drifted a few feet above the reef. Since our boat driver followed us in the deep part of the channel, all we had to do was gape, float and be awed.

To the two Hawaii island members of our group who were particularly interested in corals, Ulong Channel was such nirvana they asked our guide to go twice. There were no objections.

The other favorite, Jellyfish Lake, is a must-see for snorkelers worldwide. The golden jellyfish, often called by their scientific name Mastigias (ma-STIJ-ee-us), are found in a single land-bound lake. Fissures in the surrounding limestone island are the lake’s only connection to the ocean.

Each morning, an average of 5 million pulsing jellies swim to the east side of the lake and gradually move west with the sun, continually rotating their bell-shaped bodies. The traveling and twirling give the algae living in the jellies’ tissues enough sunshine to manufacture the carbohydrates that feed the jellyfish.

The symbiotic system is so efficient that the jellies, ranging from fingernail-size babies to teacup-size adults, no longer need to eat live plankton and therefore have no stinging tentacles. To drift among these graceful rhythmic creatures is to feel the heartbeat of Palau.

I loved the Ulong corals and golden jellies, but when I got so close to several tiny mandarinfish that I could take halfway decent pictures, I nearly wept with joy.

Only 2 to 3 inches long, the paisley-patterned mandarinfish are found only in the Western Pacific, where they hide among coral litter. The uncommon little fish are hard to find, but if you’re as lucky as we were and have a great guide as we did, the fish can sometimes be spotted at dusk when they emerge to mate.

For us the little darlings practically posed for our cameras. To be eye to eye with a curious mandarinfish in 2 feet of clear, calm water ranks at the tippy top of my list of superb snorkeling experiences.

I’m happily home on Oahu now, but Palau’s Crayola-colored corals, gilded jellyfish and decked-out mandarinfish will sparkle in my mind forever.

mandarinfish


Marine biologist Susan Scott writes the newspaper column, “Ocean
Watch”, for the Honolulu Star-Advertiser, www.staradvertiser.com

©2014 Susan Scott

Dolphins frequent shoreline to snack and let us interact

Published November 3, 2014 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2014 Susan Scott

©2014 Susan Scott

Tin Can Bay, Queensland, Australia » Last week I visited one of the friendliest, most lovable families in Australia: the dolphins of Tin Can Bay.

Even if a group of Indo-Pacific dolphins hadn’t come to the shoreline each day to play with people and eat free fish, a visitor just has to stop at a place named Tin Can Bay. After putting my sailboat up for the cyclone season, I rented a car and drove to the cove.

Tin Can Bay is a fishing town of about 2,000 residents located in a deep, narrow inlet of the same name. The name has nothing to do with canned goods, but arose from the indigenous word “tuncanbar,” meaning dugong, another species that frequents the harbor’s calm water.

The dolphin phenomenon began in the 1950s when an injured male dolphin languished near a restaurant pier. Residents fed the animal, and after he recovered he remembered the kindness (and free food) and returned daily for a meal.

Eventually a female also came to the pier, and in 1991 she brought her baby. Today four dolphins from four generations arrive every morning at about 7 a.m. They have fun with people until 8 a.m. and then get one 6-inch-long fish from each person waiting in line for the privilege (about 30 when I was there).

Researchers restrict the number of fish the dolphins are given, making the feeding a light snack before a day of normal foraging.

Standing in the water with the dolphins costs $5, and another $5 buys a fish. The money supports research on the pod and supervision of human-dolphin interactions.

Cheerful volunteers had us turn off our ring tones and camera flashes and explained that touching is forbidden. As with most wildlife encounters, though, if the animal wants to touch you, that’s fine.

I waded knee-deep into the water, immersed my hand and waited. I was the first one there (surprise, surprise), and the exuberant 2-year-old, Squirt, nudged my hand with her snout. Then, ever so gently, she took my fingers between her long, narrow jaws. The thrill of feeling a wild dolphin’s roundish teeth on my hand will stay with me forever. I’m smiling just writing about it.

Some people don’t approve of this feeding and mingling, but I do. This mom, dad, daughter and auntie are ambassadors for all Indo-Pacific dolphins, a coastal and estuary species threatened by just about everything we humans do, from fishing to development to pollution.

To protect an animal we have to love it, and to love it we have to know it. Because of these special dolphins and their hospitable guardians, each day 30-some people from all over the world meet and fall in love with Indo-Pacific dolphins. It just may save them.


Marine biologist Susan Scott writes the newspaper column, “Ocean
Watch”, for the Honolulu Star-Advertiser, www.staradvertiser.com

©2014 Susan Scott

So many fantastic colors decorate snorkeler’s view

Published November 10, 2014 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2014 Susan Scott

Razorfish bob at the Koror boat ramp in Palau. ©2014 Susan Scott

KOROR, PALAU » Soon after I started studying marine biology at the University of Hawaii, I arranged to take scuba lessons and set off to Waikiki to buy my gear.

“You came at good time,” the enthusiastic shop owner said. “My cousin is here. She is one lady from Palau!”

I didn’t get the significance of that statement at the time, but I do now. I am currently one lady in Palau.

Palau is an island nation in Micronesia about 400 miles north of the equator. The country of more than 500 islands, mostly enclosed in a barrier reef, has fewer than 20,000 residents, but the place is bustling. Like me, people from all over the world come here to dive and snorkel Palau’s spectacular Rock Islands.

The 70 or so islands are dollops of limestone surrounded by turquoise lagoon waters. The stunning result, famous in aerial photos, looks like a bunch of green-capped mushrooms floating in clear blue soup.

Among Palau’s islands grow about 600 species of rainbow-colored corals that host just about every kind of marine animal in the tropical Pacific. Researchers think this area may be the evolutionary cradle of Pacific marine life. For snorkelers and divers, Palau is heaven on Earth.

Because I flew here from Australia, I arrived two days before my seven snorkeling companions, all of us on a trip arranged by the San Francisco-based Oceanic Society. We would be snorkeling from a boat each day, and that left me on my own walking the town of Koror.

I ended up near a boat ramp where a boy, fishing, yanked up a squid. After that little excitement, I spotted in this body of clear water lining the city two blue trevallies, their iridescent blues sparkling in the morning sun. Below them, nestled among bright corals and darting fish, lay eight giant clams, each modeling its own unique algae outfit. (As with corals, the colors in giant clams’ tissues come from symbiotic algae.)

I practically ran to my nearby hotel to get my snorkeling gear.

“Watch out for the sharp oysters,” called a friendly local, when he saw me walking down the concrete ramp with swim fins and mask. “And check out the clams.”

Oh, I did, as well as a dozen other marine animals that I usually see only in my dreams. A school of razorfish bobbed vertically, as they do, looking like a school of buoyant carving knives. As you swim toward these fish, they don’t flee, but turn on edge, nearly succeeding in being invisible.

Pajama cardinalfish (so named because they look like they’re wearing polka-dot jammies), banded pipefish and so many other fantastic fish and invertebrates caused me to snorkel until my face ached.

And I’m still in town waiting for the excursion.

How wonderful it feels to be one lady in Palau.


Marine biologist Susan Scott writes the newspaper column, “Ocean
Watch”, for the Honolulu Star-Advertiser, www.staradvertiser.com

©2014 Susan Scott