Monthly Archives: April 1996

Fish’s sex lives may offer insight to human mating

Published April 29, 1996 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1996 Susan Scott

WHEN I was in sixth grade, my friends and I became keenly interested in biology. One of our favorite pastimes was searching for sex words in an older sibling’s biology textbook.

We whispered over gonads, giggled about gametes and blushed at the mention of genitalia.

One day, my friend came to school with a new word, hermaphrodite, from her big brother’s book. We looked it up: an organism having both male and female reproductive organs. We stared at each other. You were either a girl or a boy, weren’t you?

The concept was so confusing, we chalked it up as another of the many secrets of sex.

Now my interests have turned to the marine world, and I still find hermaphrodism a mystifying subject. On the reef, being male or female is anything but clear-cut.

Take nudibranchs. These snails-without-shells, also called sea slugs, are true hermaphrodites, having male sex organs on one end, female organs on the other. When these creatures have sex, they line up end to end, sometimes several individuals at a time, creating a kind of conga-line orgy.

Researchers also have discovered more than 100 species of hermaphrodite fish, and suspect that many more exist. Fish, however, vary in hermaphroditic types.

FISH equipped with both testes and ovaries are called simultaneous hermaphrodites.

One such type of sea bass spawns about 14 times a day. About half the time, the individual releases eggs; the other half sperm. This fish can switch from one to the other in 30 seconds.

As these sea bass grow older, their female gonads grow larger, causing the fish to release more and more eggs and less and less sperm. This probably increases the species’ reproductive success rate since most eggs get fertilized, but most sperm don’t link with eggs.

Other simultaneous hermaphrodite fish grow more male tissue as they age. Usually, these fish keep changing, eventually becoming all male. Fish that change sex completely like this are called successive hermaphrodites. Wrasses, parrotfish, some gobies and several other reef fish are in this group.

Successive hermaphrodites perform sex-change acts in a variety of ways, depending upon the species and circumstances.

In clownfish (those cute orange fish that live with anemones), only the largest female and male of a group reproduce. If this large female dies, her mate becomes a female. Then the largest juvenile in the family moves up, becoming the new male.

Other fish make more than one sex change. In Japanese reef gobies, a female in a group will become male if the dominant male leaves. If a larger male joins the group, the changed fish reverts to her former female self. This sex change takes only four days.

OTHER fish, such as Hawaii’s saddleback wrasses (hinalea lau-wili), have two different types of males in one species. Each varies in size and mating approach.

Such a two-male species, the midshipman of Northern California, has been studied extensively. Type I males take longer to mature, but grow bigger and develop strong vocal systems for courting.

These males, whose gonads account for only 1 percent of their weight, hum to attract females to their carefully built nests.

Type II males, however, mature early. Their gonads account for a whopping 9 percent of their body weight. (This would be 16 pounds of testicles on a 180 pound man). And humming to attract mates? Forget it. These males use invasion to get mates, stealing both nests, and the females in them, from type I males.

This sure sounds familiar. In fact, many marine scientists believe fish and people have enough in common to make studies of fish sex worthwhile. Perhaps learning what goes on in the brains and bodies of fish will unlock some of the mysteries of human sexuality.


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

 

Sick sailor will likely bring anti-Vibrio drugs next trip

Published April 22, 1996 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1996 Susan Scott

RECENTLY, I read a news story about a sailor with a leg infection who Navy SEALs rescued near Fanning Island.

Because Fanning has no airstrip, four SEALs loaded with medicine parachuted from a plane, swam to the anchored sailboat and started intravenous antibiotics on the sick man. Soon after, they set sail for nearby Christmas Island where the Coast Guard flew the man to Tripler Medical Center.

Wow, I thought. Now there’s some serious attention for a boo-boo of the leg.

Was the whole thing really that urgent? Didn’t this cruising sailor have antibiotics on the boat? Is this one of those eat-you-up infections?

I called the sick sailor, Dave Baker, who invited me to come visit him at Tripler. There I found a pleasant, articulate man, previously in excellent health, with an enormous dressing over his left calf and ankle.

I also learned that yes, it had been urgent; yes, there had been antibiotics on the boat (but not the right ones); and yes, this was one of those extremely virulent infections.

Dave was still reeling over the incident. It began as an everyday fishing affair: A tuna thrashing in the cockpit of the boat poked Dave’s ankle with the hook in its mouth.

“The hook got you good?” I asked him.

“No, it barely scratched my skin,” he replied. “I just had two tiny marks where the points touched me.”

THE next day, however, Dave and his companion saw trouble brewing. The ankle began to redden and swell, and blisters crept up his calf.

In spite of taking both kinds of antibiotics from their medical kit, Dave’s temperature shot up. The leg, and the man’s overall health, deteriorated rapidly.

After describing these symptoms over the radio to Honolulu, the decision was made to do the SEAL rescue. It probably saved Dave’s life.

Doctors on this case believe the culprit bacteria infecting Dave’s wound was Vibrio vulnificus, a notorious organism known for its fast and lethal punch.

Vibrio bacteria occur naturally in warm seawater and estuaries throughout the world. Researchers recently identified Vibrio species on rocks, on marine animals and in the water surrounding pristine islets 185 miles from Baja.

Vibrio vulnificus usually enter the body either from eating contaminated raw shellfish (about 60 percent of cases) or through marine wounds. These bacteria multiply rapidly, quickly overwhelming the body’s defenses.

COMPARED to Staph and Strep infections, Vibrio vulnificus infections are rare. When they do occur, however, they can cause amputation or death.

In Florida, from 1981 through 1992, 72 people were infected by eating raw oysters. Thirty-six of those died. During that same period, 53 Florida people got the same infection from wounds. Eight of these victims died.

Most deaths occur in people with liver disease or in those with damaged immune systems. Healthy people, however, can also succumb, especially without appropriate antibiotics.

Few cases of Vibrio infections occur in Hawaii, but this is still a bug to watch out for.

Although any wound can become dangerously infected, Vibrio infections spread remarkably fast, and quickly look like the worst infection you’ve ever seen in your life.

Sailors, fishermen and others in remote areas should carry antibiotics that kill Vibrio as well as the more common Staph and Strep. Get these prescription drugs, and instructions on their use, from your doctor.

Fortunately, Dave Baker will live and return to his boat on two good legs. And, I’m sure, in his two good arms will be a load of Vibrio-effective antibiotics.


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

 

Let these sea lions live, and let humans pay instead

Published April 15, 1996 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1996 Susan Scott

WHAT happens when a dwindling species gets protected, makes a comeback, then becomes such a nuisance that people want to start killing it again?

That’s the $64,000 question in Seattle lately, where a group of clever California sea lions has figured out the Ballard Locks fish ladders.

Actually, there’s not much ingenuity required. People built fish ladders because the locks between Puget Sound and Lake Washington prevent steelhead trout from returning to their freshwater spawning grounds. Such ladders enable steelheads to climb the locks and enter the lake.

Since finding fish is a sea lion’s job, this, naturally, is where a bunch of them loiter. They are amply rewarded by this choice of hangouts.

Sea lion number 17, named Hondo, is the biggest California sea lion on record, weighing 1,084 pounds. The usual range for these adult male sea lions is 750 pounds to 1,000 pounds.

Hondo and his cohorts are being blamed, in part, for the depleted stocks of steelhead trout.

Because of this shortage, many people want the sea lions gone. Air horns, firecrackers and rubber bullets, however, did not permanently scare the sea lions away. Neither did net barriers, transporting several of the culprits 900 miles south or locking up Hondo in a zoo for a season.

WHEN the dust settled, the sea lions were back. Now the state of Washington has received federal approval to shoot the worst offenders.

My question is this: What is a steelhead trout anyway?

Seriously. What are trout doing wandering around in the ocean? I thought trout were fly-eating fish living in rushing, Rocky Mountain streams.

Indeed they are. The surprise is that humans put them there. In fact, humans have transplanted these natives of the North American West Coast to rivers and streams all over the world. And there they thrive.

Rainbow trout are perfectly happy spawning and living their entire lives in fresh water, while steelhead trout need the ocean to live – and they’re both the same species.

They are, however, different races. Steelheads are called the sea-run race; rainbows are the freshwater race.

So. Back to sea lions. Will killing the biggest sea lions chowing down at the Ballard Locks help the steelhead situation? Maybe. But not for long.

In this world of survival of the fattest, other sea lions will soon be the kings of the locks and grow equally large. Then wildlife officials will again be faced with a difficult decision.

And this is a tough situation for wildlife workers. Although they are depicted as the bad guys in this by animal-rights activists, I can’t imagine one marine biologist I know enjoying the prospect of shooting a sea lion, especially such a prime specimen as Hondo.

I can’t see how killing three or four of a zillion sea lions is going to help the fish for long.

And neither can animal-rights activists. Some are threatening to sue, and others are rowing around in little boats near the Ballard Locks wearing red bull’s-eye targets.

The latest word from Seattle is that a marine park in Florida has offered to take five of the worst fish felons.

“No,” say the activists. “These wild animals should not be imprisoned. Redesign the locks so the sea lions can’t get the fish so easily.”

Rebuilding the fish ladders is a good answer. The rub is that it would cost a fortune in tax dollars. Trout and salmon (also suffering critical shortages) have lived with seals and sea lions for eons and have done just fine.

It’s we humans that have messed up the balance of their world; it’s we humans who should pay the price.


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

 

Ciguatera is common, but it may not be golf’s fault

Published April 8, 1996 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1996 Susan Scott

A reader recently asked me to write a column on ciguatera fish poisoning.

“Is there anything particular you’d like me to write about?” I asked.

“Yes,” she said. “I think you should let people know that pollution running off the island, especially fertilizers from golf courses, is making ciguatera worse.”

Is it? I wondered. She sounded so sure.

I called University of Hawaii marine toxin specialist Dr. Yosh Hokama. “What a coincidence,” Dr. Hokama said when I told him the story.

“Just yesterday we asked the UH Sea Grant Program for funding to study the growth of algae and other marine organisms off Hawaii’s golf courses.

“We know that golf courses change the quality of the water around the areas they are built. Some studies show that after each rainfall, algae bloom and some dinoflagellates proliferate.

“But what effect this has on marine toxins – we just don’t know yet.”

BESIDES runoff pollution, our porous islands also allow rain, fertilizers and other surface substances to soak through the soil, entering the ocean through underwater springs.

Injections of such nutrients into surrounding waters, from both runoff and seepage, are like showers in a desert. Tiny marine plants and animals thrive.

Is this causing ciguatera fish poisoning to increase in Hawaiian waters?

It’s a leap that Dr. Hokama isn’t willing to make. No one knows yet if such blooms also include an increase in numbers of the dinoflagellate that causes ciguatera fish poisoning, Gambierdiscus toxicus.

Perhaps growth of this organism is a normal, fluctuating condition of the ocean that has little to do with human proceedings.

Ciguatera is not a new affliction.

It was described in 1606 in Vanuatu (formerly the New Hebrides) and was undoubtedly present long before that.

TODAY, it is the most common cause of seafood poisoning in the United States. It is also common in certain Caribbean and South Pacific countries.

About 50,000 cases per year are recorded worldwide from many places that don’t have golf courses or much else in the way of development.

It is true that more cases of ciguatera have been reported in Hawaii and the world during the past two decades than ever before.

But more people are fishing, and eating fish, than ever before. Also, public awareness of this poisoning is higher today than in previous decades, resulting in more reports of the illness.

The number of cases reported in Hawaii over the past six years shows no trend.

In 1989, there were 84 cases reported. In 1990, 52 cases; in 1991, 138 cases; in 1992, 34 cases; in 1993, 86 cases; and in 1994, 63 cases.

Dr. Hokama and his colleagues are also interested in the 1994 illness of eight people who ate “short ogo” (limu manauea) from Maui.

One of Dr. Hokama’s workers recently discovered a blue-green algae growing on the surface of the suspect seaweed. That algae produces aplysatoxin, a potent marine poison.

No one knows what caused this unusual growth.

ARE golf courses trouble for Hawaii’s ocean waters? The only way to know for sure is to spend money on studies.

I know, there’s little funding for such research. But without examining the situation with rigorous scientific standards, it’s all just guesswork.

Hippocrates said, “There are two things, science and opinion; the former begets knowledge, the latter ignorance.”

I hope Dr. Hokama gets his grant.


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

No fooling – government must make trailheads safe

Published April 1, 2013 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1996 Susan Scott

LAST week, after several frustrating computer crashes, I decided to treat myself to a hike at Kaena Point Nature Park. I drove my car to the end of the road where I parked in a clean, paved stall.

As I got out of the car, a police officer patrolling the area on a bicycle greeted me.

Quietly, we discussed the beauty of this exquisite wilderness. Moments later, I started my hike with a feeling of gratitude that such a serene place exists on this otherwise frenzied island.

APRIL FOOL!

Here’s the real story: Last week after several frustrating computer crashes, I treated myself to a hike at Kaena Point Nature Park.

When I arrived at the trailhead, I felt even more depressed. Broken glass lay everywhere in the pitted, dirt field. Motorcycles and four-wheel-drive vehicles charged unrestrained around the so-called gate, creating such a racket that I had to shout to a friend standing right next to me to be heard.

IT took more than two miles of walking to get away from the dust, smoke and noise. We returned to the car a couple hours later, covered in red dirt – as was my car. The dirt was so thick, I couldn’t see through the windows to drive. After a pathetic attempt to clean them, I grumped home, both car and driver filthy.

“It’s just the weekend,” I rationalized. “I should only go out there on weekdays, when it’s quieter.”

So I did, a few days later. It’s true there were fewer trucks and no dirt bikes barreling around inside the gate. This time, however, I came back to my car to find that I could see out the window just fine – because it was gone. So was every single item in the car.

I drove home in a sea of broken glass and called police. They wouldn’t come to my North Shore house. Why?

“You wouldn’t believe the number of break-ins like this that happen out there. We can’t possibly come for each one,” I was told.

Uh, isn’t there a clue there? I wondered out loud. The officer sighed and I knew what was coming: not enough money; not enough officers.

THE good part of this wretched story is that on both hikes, after I got through the vehicular battlefield and before I found my car trashed, I fully enjoyed myself.

At the far end of Kaena is a true pot of gold. This small section of preserve lies behind a real barrier, not a pretend one, and holds a wonderland of native plants and animals.

What was once wasteland now blooms. I watched a monk seal snooze on the beach there and saw courting Laysan albatrosses dance. Just offshore, baby humpback whales entertained me with playful breaches.

There’s no arguing that Kaena Point is a jewel, a marvel of rebounding nature. But how can residents or visitors enjoy it? People here on the North Shore just shake their heads when I say my car was vandalized at Kaena Point.

“You left it THERE?” they say. Then they tell me a worse story of what happened to their car at some other trailhead.

THIS is the third car hit in my family in a year and a half. The worst two were at trailheads. What do we do now? Stop hiking? Rent a car when we go on a hike? Hire a guard? Not one of these ideas is reasonable.

What is reasonable is for government agencies to work together to enforce gate rules and make trailheads safe. I know funds are tight. But what good does it do to spend money on pseudo-barriers when people can easily drive around them? And how can we taxpayers justify spending money to maintain nature parks that we’re afraid to use?

I am appalled at how many people pointed out how lucky I am that the brick was thrown at my car window instead of at my head.

Clean, safe parks and trailheads on Oahu should not be an April Fool’s joke.


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