Bleaching isn’t always death knell for corals

Published November 11, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Many scientists believe that the Earth is headed for a sixth wave of mass extinctions, with humans rushing the rate. Corals will be among those affected, but one small sign of encouragement is that some corals are adapting to changing conditions. Susan Scott snorkels off Kelso Reef, Australia. Courtesy Craig Thomas

Since I returned from Australia last week, people have been asking what I think about coral reef bleaching. Do I believe humans are causing it, and, if so, can we fix it?

The questions refer to reports of corals turning white in areas of Australia’s Great Barrier Reef, and other reports about Hawaii’s reefs. Between 2014 and 2015, scientists found bleaching in 56 percent of corals off the Big Island, 44 percent off West Maui and 32 percent around Oahu.

So-called bleaching occurs when overly warm ocean water causes corals to ditch their algae. The corals’ clear bodies then expose the white calcium carbonate cups that support them.

Researchers theorize that this occurs because overheating causes the plants to make more oxygen, and too much of the gas creates free radicals, a single O instead of the usual O2. Lone oxygen atoms are toxic to animal cells.

The good news is that bleached coral isn’t necessarily dead coral. A coral can live for a while without its plants because its tentacles sting and eat passing animal plankton. When the water later cools, such as after El Nino years, live bleached corals catch algae drifting past in the water. When the plants multiply, they put the color back in corals’ cheeks.

Because bleached corals eventually need carbs, however, if the water stays warm, the corals can’t replenish their crops and die.

This isn’t the first time on Earth that corals have been in trouble. The first reefs formed 490 million years ago, and since then five mass extinctions caused by asteroids, climate change, volcanoes and sometimes more subtle changes killed all reef-building corals. The extinctions took 1 million to 2 million years each, and hundreds of millions of years for new species to evolve.

Most scientists believe we’re on the verge of a sixth extinction. The difference this time is that we humans are rushing the rate. What would normally take 140,000 years for a species to disappear now takes 100.

Homo sapiens is one of those species. In their bright white way, reef-building corals are our putting us on red alert. We are paving the road to our own extinction.

I doubt we humans will mend our ways in time. Our animal instincts to reproduce, fight, and segregate families and tribes from one another make uniting for a common cause tough.

But because species evolve to changing conditions, there’s hope. Some corals are adapting to higher water temperatures and doing just fine. Perhaps, as human and wildlife suffering escalates worldwide, our species will evolve to become less selfish.

In the meantime, there’s tremendous beauty left on the planet, and we should get out there and enjoy it. And who knows? By each of us volunteering to the charity of our choice, we may be accelerating our species’ evolution to altruism.

Spiral float is unique to 1 species of cuttlefish

Published November 4, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Each cuttlefish species has a distinct shape, size and ridge pattern in their buoyancy bone. Cuttlefish bones from Horseshoe Bay, Magnetic Island, Queensland, Australia, are displayed. ©2017 Susan Scott

I’m home from Australia after several outstanding voyages to the outer reefs of the Great Barrier Reef Marine Park. As is often the case, though, a highlight of the trip was a beach walk where I found perfectly intact shells of two kinds of cuttlefish: the common cuttlefish (Sepia) and the ram’s horn cuttlefish (Spirula).

These weren’t rare finds because the creatures’ skeletons are common on beaches here. In collecting some of the shells, though, and looking them up in a new doorstop book I bought for the boat, I was in for a surprise. When I studied invertebrate zoology in the 1980s, I misread a textbook caption, and since then have been merrily spouting half-truths about cuttlefish.

Cuttlefish belong to a group of creatures known as cephalopods, a class of mollusk (snails, clams, etc.) that includes nautilus, squids and octopuses. About 120 species of cuttlefish live throughout the world, but you won’t find their skeletons in Hawaii or on beaches in the Americas. Cuttlefish existed before Earth’s land masses split into continents, and that process isolated cuttlefish from some ocean areas.

Cuttlefish look like roly-poly squid, both having two big eyes and 10 tentacles around the mouth that reach out and grab anything they can catch, including other cuttlefish. In turn, just about every marine predator in the world, from fish to dolphins to seabirds, eats cuttlefish.

Most people know cuttlefish from the white, oval shells called cuttlebones that we hang in our pet bird cages as calcium supplements. Pet supply companies don’t have to search hard for the product. The bones float after the cuttlefish dies, and the white rafts of every size, from 1 to 20 inches long, litter Australia’s water surfaces and beaches.

In life, the cuttlefish’s porous calcium-type bone lies under its skin along its back like a flat backbone. By adding or removing air and water in the bones’ spaces, the animal controls its buoyancy.

The tiny cuttlefish species called the ram’s horn, however, lacks a flat cuttlebone along its back. Instead, near its rear end lies an internal spiraled shell, this species’ buoyancy controller. After the ram’s horn cuttlefish dies, its spiral also floats and drifts ashore.

My decades-old error was thinking (and telling anyone who would listen) that the spiral floats were inside all cuttlefish. In fact, each cuttlefish species has its own distinct shape, size, texture and ridge pattern in its buoyancy bone. My aha moment was in learning that the 3/4-inch-tall spirals come from a single deep-sea species, and that it has the charming common name of ram’s horn cuttlefish.

This is why, even after squishing my face and blistering my heels with weeks of superb snorkeling, beach walks remain high on my list of favorite activities.

As does buying heavy, expensive marine animal guides.

Sea snakes seen sunning amid Great Barrier Reef

Published October 28, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Sea snakes, which carry venom used to paralyze prey, can make for good swimming and snorkeling companions, if one doesn’t fear them. ©2017 Susan Scott

KELSO REEF, AUSTRALIA >> After sitting out a week of rain in Magnetic Island Marina, we’re back in flat water, moored on another of the Great Barrier Reef’s pristine outer reefs. Snorkeling here at Kelso Reef is as good as it gets, but even so, we don’t have to get in the water to be thrilled. We just stand on the deck.

While sailing between the mainland and the outer reefs these last few weeks, we’ve seen four sea snakes sunbathing on the water’s surface. Three dived before we could turn the boat around for pictures, but one, a tan-colored beauty with dark saddles on its back, totally ignored us, continuing to nap as we circled.

The 15 species of sea snakes that live on Australia’s reefs are bold, because they’re packing. All carry cobra-type venom stored in cheek glands connected to two front fangs. Injected toxin paralyzes muscles almost immediately, handy for halting fast-swimming prey, such as the bottom-dwelling fish that most snakes like to eat.

The good news is that sea snakes don’t waste their venom on snorkelers or divers. Australia reports no deaths from sea snake bites.

Even though we’ve seen sea snakes basking on the water’s surface this month, I’ve not seen a single one while snorkeling. That’s partly by chance, but it may also be because some sea snakes don’t like to travel.

In a study of olive sea snakes, the Great Barrier Reef’s most common species, researchers found the snakes’ foraging areas were only half an acre. When workers moved some individuals from their home reef to an adjacent one 200 yards away, none crossed the sandy channel to get back.

Sea Snake. New Caledonia 2006

That might explain why sea snakes are common on some reefs and absent on others, but it makes me wonder about the snakes we see basking on the surface miles from the nearest coral reefs. Maybe like us humans, some sea snakes are wanderers and others are homebodies.

All sea snakes are air breathers, but because they have one cylindrical lung nearly as long as their bodies, they can stay submerged for up to two hours.

Olive sea snakes come in shades of solid green, gray or golden yellow. Our first three snake sightings were olives. The species has light sensors on its flat, paddlelike tail, a feature that tells the snake whether its rear end is sticking out. When you’re 6 feet long, eye spots on your tail are handy for hiding under a coral head.

For us sailors, though, eyes peering through polarized sunglasses are all we need to spot a sea snake snoozing on the water’s surface.

I know I’ll never convince people who fear snakes that they’re fun snorkeling companions. But even those with phobias might appreciate seeing, from the deck of a boat, a rare marine animal in its natural element.

Or not, if it’s a snake.

Banded Sea Snake on land, New Caledonia, 2006. Courtesy Scott R. Davis

Underwater ‘banquets’ are a feast for the eyes

Published October 21, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A giant clam sits on a bed of coral in Britomart Reef in Queensland, Australia. ©2017 Susan Scott

ORPHEUS ISLAND, AUSTRALIA >> After nearly a week of snorkeling on the outer reefs of the Great Barrier Reef Marine Park, stormy weather forced Craig and I to sail our 37-foot boat, Honu, back to the shelter of this island. Although Orpheus is also a national park with its own charming beaches, birds and reefs, we missed our giant clams.

While anchored on the reef, we had discovered a several-acre area that looked like the site of a mermaid’s banquet. Table after table was set with pink, green and lavender plate corals sitting between runners of gold and tan leather corals. In the midst of these place settings sat dazzling centerpieces: blue, green and gold giant clams.

A major downfall of these beautiful bivalves is that they’re sitting ducks, big pieces of meat that can’t run away and have only minimal defense. (They can close their shells somewhat but don’t slam shut like they do in cartoons.) Because the colorful algae in their soft tissues need sunlight to thrive, the clams grow mostly in clear, shallow water, making them easy to find, kill and eat.

Like stony corals, giant clams host algae in their tissues that grow sugars for the clams. If conditions are prime and the algae get too dense, the clam simply eats them, too.

A giant clam gathers fertilizer for its algae directly from the seawater that bathes it. Covering the soft, gaping lips of the creature is a type of tissue that can absorb ammonia, nitrate and phosphates, nutrients crucial for plant growth.

The clam breathes, and gets nutritional supplements, by inhaling water through a round siphon on one end of its soft body and sifting out tiny plants, animals and oxygen. The filtered water exits out another siphon on the clam’s opposite end.

Because giant clams grow well in tanks, aqua-farmers in Palau, the Philippines, the Cook Islands and other areas grow them for food, for the aquarium trade and to replenish reefs where people have overharvested.

Giant Clams being grown in a tank in the Cook Islands. ©2006 Scott R. Davis

Just when Craig and I were reminiscing about our amazing experience in what we named the Super Duper Royal Clam Garden, we made a joyful discovery. Near the James Cook University’s marine science center in Orpheus Island’s Pioneer Bay, researchers had planted a giant clam garden in the 1970s.

We found the man-made plot by accident while going ashore in our dinghy. From the surface we could see the 3-foot-long creatures smiling up at the sun, their oval bodies resembling iridescent place mats, and their siphons projecting from the flesh like white porcelain cups. Today 40 to 50 (my guess) mature clams thrive there.

Swank dinner parties aren’t Craig’s and my usual thing, but last week we attended two and we didn’t get a bite to eat. In giant-clam gardens the feast is for the eyes.

Colorful Giant Clams-Bora Bora, French Polynesia. ©2006 Scott R. Davis

Coral-eating starfish have their place in healthy reefs

Published October 14, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A crown-of-thorns starfish eats live coral bodies, leaving their white skeleton cups intact. ©2017 Susan Scott

BRAMBLE REEF, AUSTRALIA >> On our sailboat, Honu, no wind means using the boat’s loud, hot motor to go somewhere, something we sailors resist. Last week, though, the lack of breeze and Honu’s diesel engine were a godsend, allowing us to explore sections in the outer area of the Great Barrier Reef Marine Park.

Being out in the Coral Sea, anchored in striking white sand patches surrounded by city-block-size coral heads and boulevard-wide reef flats was a wilderness experience like no other. We snorkeled for hours on end, and each time we rested, the same word came to both Craig and I in describing what we saw: pristine. These reefs are among the few remaining places on Earth that show no sign of human disturbance.

In some areas, though, nature had wielded a heavy hand. Massive coral heads lay on their sides, and car-size table corals stood upside down, tipped over by cyclone-­driven waves.

We also saw crown-of-thorns starfish, the largest of all starfish species, slurping the soft bodies out of corals’ hard cup skeletons. The starfish everts its stomach through its mouth, oozes digestive juices onto the live coral body and sucks it up, leaving only the white calcium carbonate cup.

Crown-of-thorns starfish, COTS for short, have 10 to 20 arms, grow to 20 inches across and are a normal part of healthy coral reefs. Coral deaths open space for juvenile plants and animals to settle, thus giving reefs variety in shapes, surfaces and species that can withstand, and recover from, natural damage, including starfish blooms. Of the reefs we visited, however, in two places COTS were clearly more numerous than a healthy reef can handle.

COTS blooms have been a threat to the Great Barrier Reef since the 1970s. Researchers once thought that human collecting of the giant triton snail, called Triton’s trumpet, was to blame, since the snail eats COTS. The outbreaks, however, aren’t caused by a shortage of starfish predators, but rather by the survival of exceptional numbers of the starfish’s babies.

River runoff causing algae blooms that feed drifting starfish larvae is another suspect. But COTS outbreaks also occur off remote islands where there’s no such runoff.

Of the 100-some COTS research papers published over the decades, the cause of the blooms remains the same: unknown. It may be a normal part of reef evolution.

Just when we started to worry about COTS destroying these pristine reefs, the starfish vanished. The next acres of reef had zero COTS, and the corals, fish and giant clams sparkled with such beauty, I felt happy to be alive.

Sailboats might need the wind to sail, but sitting becalmed on the Great Barrier Reef, sunny day after sunny day, landed us smack in the middle of ocean paradise. Now that’s a godsend.

Crown of Thorns starfish, French Polynesia, 2006. Courtesy Scott R. Davis

Colorful ocean plant also reeks of dead fish

Published October 7, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Sea sawdust blooms in the Coral Sea, forming strips of growth so large that they’re visible in satellite photos. ©2017 Susan Scott

TOWNSVILLE, AUSTRALIA >> Last week a Tahitian snapper made itself known to me by opening its own page in my fish book. This week an ocean plant I didn’t know called attention to itself by floating around Honu’s hull in swirls of yellow, purple and pink. With the plant came its signature smell, the nose-wrinkling stink of dead fish.

The alga — scientific name Trichodesmium (trick-o-DEZ-me-um) — is commonly called sea sawdust. Australian boaters know this marine alga well because it occasionally blooms in the Coral Sea, forming strips of growth so large they’re visible in satellite photos.

The streaks the alga sometimes forms on the ocean’s surface spooked Capt. James Cook and his crew in 1770. In his log Cook wrote, “The sea in many places is here cover’d with a kind of brown scum … upon our first seeing it, it alarm’d us thinking that we were amongst Shoals.”

They were not, however, in shallow water, but were sailing through miles of one of the most vital marine plants in our planet’s oceans.


Trichodesmium is a blue-green alga that grows as tiny filaments, like miniature grains of rice. Usually, the barely visible seaweed lives in the water column where endless tiny animals eat it. During blooms, though, thousands of alga strands stick together and float to the surface in miles-long lanes of sea sawdust.

Sometimes the alga produces substances that are toxic to fish and irritating to human skin. Other times, depending on conditions, the plant produces red, pink and purple pigments. The Red Sea got its name from a red strain of this alga.

Sea sawdust is key in keeping the nutrient-poor tropical and subtropical oceans around the world productive by converting nitrogen from the air to fertilizers crucial to other marine plants.

Blooms of sea sawdust during periods of calm seas are common inside the Great Barrier Reef. People here accept the colorful alga mats and their pungent odor as part of life on Australia’s tropical coast.

Trichodesmium films smell fishy because when each plant dies, its cell wall breaks down and the insides spill out. Bacteria eat the spillage, a meal that gives them gas. Called dimethyl sulfide or DMS, the gas is one of several fishy odors we associate with the ocean.

As we set about provisioning Honu for our latest voyage in the Great Barrier Reef Marine Park, Craig and I marveled over the colorful eddies around the boat, a vision worthy of an exhibition in a modern art museum. And the odor? Well, learning the chemistry of the plant, knowing the significance of it to the world’s oceans and remembering that bacteria pass gas like everyone else took the smart out of the smell.

I’m in no hurry to sail Honu out of this marina, because it’s in the central part of the Great Barrier Reef Marine Park, pure heaven for us oceangoers. All I have to do is open my eyes, breathe in deep and, like the Tahitian snapper, let the marine life come to me.

Mystery fish is revealed as snapper from Tahiti

Published September 30, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A Tahitian fish called the blacktail snapper can be found in Hawaii. This fish was found at a Ko Olina lagoon. Courtesy Gary Walden

Reader Gary Walden snorkels most days in Ko Olina Lagoon No. 4 and emailed the following, with a picture: “I cannot find the name of this fish.”

I didn’t know the fish name either, but thought it was probably one of Hawaii’s rascally wrasses. Those reef fish are tricksters to us snorkelers because worldwide there are 460 species in the family, and of those, Hawaii hosts 43.

That might not be so hard to sort out, except that some baby wrasses look so different from their parents that in the past, researchers considered the youngsters separate species and gave them their own scientific names. The true identity of the young wrasses became apparent when they gradually changed into their adult colors.

As if that’s not enough to confuse even seasoned fish watchers, some wrasses change body color dramatically after they’re adults, switching from female to male as the need in a wrasse harem demands.

Since I was feeling a bit under the weather when I received Gary’s email, I carried my fish ID book to the couch, lay back and started paging through wrasse pictures. Nothing, however, popped out resembling the Ko Olina No. 4 fish. Frustrated and sleepy, I tossed the book toward the coffee table where it fell off the edge.

And behold! When I reached down to pick up the guide, there was Gary’s fish staring up at me. The guide had fallen open to the snapper family and lay open on the precise page.

Gary’s fish is called a blacktail, or flametail, snapper, Lutjanus fulvus. The blacktail snapper has no Hawaiian name because it’s a Tahitian fish, not native to Hawaii waters. Tahitians call it to’au.

Hawaii hosts only two native coral reef snappers (we have three deep-water species: opakapaka, ulaula and onaga) and since snappers are delicious, in 1956 state fisheries managers brought blacktails here from Moorea, an island in French Polynesia.

Those snappers were roamers. Only weeks after their release in Kaneohe Bay, anglers caught them in North Shore’s Waimea Bay and others were caught off Honolulu.

To’au never became abundant, however, and in 1958, officials tried again, this time bringing to Hawaii bluestripe snappers, called ta’ape in Tahitian, from the Marquesas.

Although the introduction was well-intended, bringing the 12- to 13-inch-long fish to Hawaii was a mistake. Even though the ta’ape did well in Hawaii waters, and the to’au are hanging in there, they never caught on as food fish. A third introduced species called the paddletail snapper is rare here today.

Even so, Hawaii’s immigrant snappers have their charms, being attractive and — who knew? — psychic too. The next time someone sends me a snapper picture, I’ll just throw my fish book at the wall and let the fish find itself.

Puffy toylike fishes aren’t to be played with

Published September 23, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Boxfish are named for their rectangular shape, formed by a rigid shell around the body. Only the fishes’ eyes, fins, mouths and tail are movable. Boxfish ooze a poison to ward off predators. Courtesy Russell Gilbert

My 10-year-old snorkeling friend Darius shouted, “I see a pufferfish!”

He pointed as we swam at Three Tables, part of the Pupukea Marine Life Conservation District.

I looked at the fish.

“That’s called a trunkfish,” I told him.

But neither of us was entirely right, nor was either of us entirely wrong. The swimming suitcase I called a trunkfish gets the heading “Boxfishes and Cowfishes” in my fish textbook, but adds in parentheses, “Also called trunkfish.”

And Darius wasn’t far off in calling the slow-­swimming fish a pufferfish. Trunkfish and pufferfish aren’t from the same family, but they’re kissing cousins.

No fish, though, wants a kiss from a boxfish. Like its pufferfish kin, boxfish carry a toxin so strong it can kill aquarium mates. And if the little boxfish gets really upset, it can exude, from its skin, enough poison in the tank to also kill itself.

Clearly, boxfish didn’t evolve to live in bowls. In the ocean the boxfish’s slippery toxin repels predators but dilutes fast enough in open water to keep the boxfish unharmed.

Boxfish poison isn’t known to kill humans, as does pufferfish poison, but still, I wouldn’t try licking one. Although some people in Asia eat boxfish, the soapy substance the fish ooze is similar to detergent.

Like pufferfish, blue-ringed octopuses, poison arrow frogs and others, boxfish hire out their chemical weapon production to bacteria. In this classic case of symbiosis, the bacteria get a place to hang their hats, and in return they manufacture sudsy slime to protect their host.

The name boxfish, and trunkfish, comes from the fishes’ rigid, rectangular shell, which covers the entire body like a knight’s armor. Only the fishes’ eyes, fins, mouths and tail are movable. A few bones support the fishes’ internal organs, but evolution has done away with most bones, including ribs.

Hawaii hosts two common species of trunkfish, the spotted boxfish and the thornback cowfish, growing 5 to 6 inches long. It seems as if there are more, because males and females of the same species look different.

The cowfish gets its name from forward-pointing “horns” on its head. When threatened, the cowfish swims backward, keeping its sharp horns facing the intruder. En guard!

Boxfish swim like little wind-up toys, propelling themselves around with amazing speed and dexterity using only side and rear fins. Members of this family eat algae, sponges, worms and small crustaceans.

I don’t fuss over animal names because, to me, as long as the person involved knows what the other person is talking about, well, the name did the job.

I’m looking forward to my next snorkeling excursion with Darius, hoping he spots another pufferfish-trunkfish-boxfish-cowfish. When you see a fish in shining armor, it’s always worth a shout.

Male Spotted Boxfish. Courtesy Scott R. Davis

Female Spotted Boxfish. Courtesy Scott R. Davis

Scorpionfish well hidden with leafy camouflage

Published September 16, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Leaf scorpionfish belong to the scorpionfish family but lack the anglers and venom that others commonly have. Hawaii is home to many leaf scorpionfish, which resemble decomposing leaves drifting in the water. ©2017 Susan Scott

I have a friend named Oakley, and when he emailed, my spam blocker apparently thought he was trying to sell me sunglasses. That’s why just last week I found in my junk mail the note Oakley sent in early August.

“We saw a pair of leaf scorpionfish at 3 tables,” he wrote. “At least I’m pretty sure that’s what they were based on my Googling. Really cool. I thought of you. Is this something common in Hawaii? Never saw one before.”

They are really cool, and yes, leaf scorpionfish are common in Hawaii, sometimes in water only inches deep. But that doesn’t mean we commonly see them. Most people don’t notice them, because they look like their namesake: a leaf. Oakley writes that the two he saw were black and looked like dead leaves drifting.

I’ve surely missed seeing countless leaf scorpionfish during my snorkeling excursions, because camouflage is their (and most scorpionfishes’) defense. But I did spot one several years ago on the North Shore.

Courtesy Russell Gilbert

I thought it was a yellowing leaf until I noticed that it didn’t move as it should when a wave passed in the 3-foot-deep water. When I looked closer, I saw a starry eye staring back at me and knew I had a treasure.

Leaf scorpionfish belong to a large family called scorpionfish, notorious for poking anglers, waders and aquarists with the fishes’ sharp back and side fins. The stings are memorable because many of the world’s 350 species are packing. Venom flows into the victim from glands at the base of the fins’ spines. Leaf scorpionfish have no such venom.

Hawaii hosts 28 kinds of scorpionfish, 11 found only in our waters. Leaf scorpionfish, though, are widespread throughout the Indian and Pacific oceans.

In most places, finding a leaf scorpionfish is a rare event, but not so in Hawaii. Look carefully, though. The longest these little beauties get is 4 inches, but most are only 2 inches.

Besides looking like decomposing leaves (the fish can be white, pink, red, yellow, black, brown, green or mottled), leaf scorpionfish are hard to spot because they collect tiny bits of algae and other marine growth on their skin.

Courtesy Russell Gilbert

When the outfit becomes burdensome, the fish molts. Shedding can occur up to twice a month and starts at the head. In less than a minute, the little leaf-fish is back to its true skin color and starts trying on new accessories.

My yellow leaf scorpionfish held still for pictures, but even when I caused it to hop, it always kept its face inward toward its coral head. This typical head-in pose of the species serves as another defense strategy.

I thanked Oakley for writing, and we made a promise to go snorkeling together soon before the north swell starts up.

I ordered sunglasses from him, too, but I’m still waiting.

Disturbing truth makes seafood unappealing

Published September 9, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

An Australian slipper lobster known as a Balmain bug. ©2017 Susan Scott

Last week when our Sydney taxi driver asked the carload of us where we were from, we shouted in unison, “Bangladesh! France! Guatemala! Hawaii!” We were in Australia attending a wedding, the groom Bangladeshi, the bride French-Guatemalan.

One of the places the French wanted to visit the following week was the Sydney Fish Market, a shore-side facility famous for artful displays of edible marine animals. Many are still alive, the bride told me. You choose something and they cook it for you. Given my interest in marine biology, she was sure I would want to go.

Oh, dear. This brought up my dilemma regarding marine life. It feels wrong to eat the animals that give me so much pleasure when I see them alive in their natural environments.

Seeing them suffocating in tiny tanks and twitching on beds of ice makes my stomach hurt. Plus, I’m aware of stock depletion, habitat destruction and the wasteful ways we catch fish.

On the other hand, it feels equally wrong not to eat marine life that someone, whose livelihood depends on fishing, has already caught. And then there are the markets and restaurants whose owners and employees earn their livings by cooking and selling fish.

According to Sylvia Earle, an oceanographer who has spent more than 50 years working to save the world’s oceans, we who have choices should stop eating all marine animals.

I can practically hear the gasps from island residents, where catching and eating fish, lobster, shrimp and crab is part of daily life. But Sylvia isn’t a fanatic. She’s a scientist who knows the data.

Factory ships put out enormous nets and lines 50 or 60 miles long, and bottom trawlers scoop up entire ecosystems. Humans’ ability to kill wildlife has far surpassed the oceans’ ability to keep up. Even more disturbing is that much of what’s caught is thrown out.

Many people think that marine animals’ sole purpose in existing is to feed us. Not so. Their roles in ocean ecosystems far outweigh our need to eat them.

This wedding, where people of several races came together to celebrate the union of two people from different cultures, was a good example of a changing world. With 7 billion people on the planet, and the oceans in trouble, I’m changing, too. I’m not a vegetarian, but more and more I’m choosing to eat plants over animals.

Except for my visit with those special friends at the Sydney Fish Market. I ordered eel because it was already dead. I had recently written about it. (I didn’t like it.)

The bride picked a slipper lobster known as a Balmain bug. When she passed me her plate for a taste, a silver gull swooped down, snatched the entire lobster tail and flew off with it.

Fair enough, I thought. Seabirds don’t have many choices.

Fortunately, we Americans do.