Monthly Archives: February 1997

Monk seals make movies with the ‘critter cam’

Published February 24, 1997 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1997 Susan Scott

One of the major problems biologists face in protecting our critically endangered Hawaiian monk seals is lack of knowledge. When seals are in the water, where do they go? What do they eat? How do they find it?

The scarcity of facts, particularly about the eating habits of monk seals, is frustrating for managers who need to know more to help the animals’ plummeting populations.

At French Frigate Shoals, the number of seals has dropped from about 800 in 1989 to about 400 currently.

Recently, though, there’s been a breakthrough in underwater seal study: Workers have devised a way for monk seals to film themselves.

National Geographic photographer Greg Marshall invented the sophisticated system, nicknamed the “critter cam.” Last summer, with National Marine Fisheries Service biologists, Marshall attached a 4-pound camera to the back of each of eight male monk seals at French Frigate Shoals.

To do this the team sedated the chosen seal. Then they epoxied the camera housing onto the seal’s furry back, just behind the neck.

When the seals woke up, they headed for the ocean and the cameras started rolling.

Daylight and saltwater immersion triggered filming, which was timed to run for 11/2 minutes every 15 minutes. After the three-hour film ran out, the team found the seals and removed the cameras.

Watching the subsequent footage feels like a breakneck ride on the back of the seal itself. But besides the thrill of getting a seal’s-eye view of the world, researchers now know something about what these marine mammals do when they disappear beneath the water’s surface.

Sometimes the seals are simply napping. The cameras recorded seals sleeping in caves as deep as 250 feet. After about five minutes, the seal would swim to the surface, take a breath or two and head back down for more snoozing.

Some camera-bearing males also spent time stalking and harassing female and immature seals. One adult male was recorded chasing, bellowing at and trying to mount a juvenile seal.

Other times, monk seals forage for food. Everyone expected this. But it was the seals’ style of hunting that came as a surprise.

Never did seals chase fish swimming in the open. Sometimes whole schools would pass by without arousing the slightest interest of the seal.

Instead, the films showed seals cruising over sandy or rocky bottoms as deep as 300 feet. Occasionally, the animal would turn over large, flat rocks with its snout, presumably looking for eels, octopus, sand-dwelling fish or invertebrates.

One time a seal caught and ate a razor wrasse. Another snatched a triggerfish. A third ate an octopus. A fourth seal rooted in and around an empty lobster trap.

Sometimes, gray and Galapagos sharks accompanied the seals during this rooting. Other times as many as 30 jacks tagged along, probably waiting for a fish or invertebrate to be flushed out by the seal’s stirring.

This information may not seem earth shattering, but in the world of monk seal research, it’s a gold mine. And it’s just the beginning.

This summer the critter cam team is planning to attach cameras to seals again, possibly in another area of the refuge.

By comparing films, researchers may find clues to the reasons behind the French Frigate Shoals’ population decline.

These critter cams belong to the National Geographic Society, which means that everyone will likely get to see some of this fantastic film work in one of their upcoming nature shows.

Watch TV listings for a National Geographic special on seals. In it our own Hawaiian monk seals will be the stars, carrying the cameras that not only entertain but may also help save the species.

Mynah gang didn’t alarm reader’s plucky plover

Published February 17, 1997 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1997 Susan Scott

My mail recently has been full of interesting marine tidbits.

Here are a few:

 On plucky plovers: I asked readers to share stories with me about golden plovers, the charismatic shorebirds that visit Hawaii each winter. Sadie J. Doyle of Honolulu sent this:

One day, years ago, Doyle heard some loud mynah bird squawking and went outside to investigate.

What she saw was “an unforgettable performance never again to be matched in all my years in Honolulu.”

There in her yard, its back to a fence, stood a golden plover facing a semicircle of mynah birds. They were “fussing and shouting mynah obscenities. Yah! Yah! Your mother wears combat boots!” they seemed to say, taking a step toward the plover, one at a time.

The plover replied by also stepping forward, facing the mynah, and delivering its own shrieking insults. The mynah backed down.

Each mynah took a turn, and each time, the plover stood its ground and “put the upstart mynah in its place.”

Eventually, the mynahs gave up. “The plover watched them depart … then proceeded to go about his little ballet as he extracted edible goodies from the ground.”

It’s a great plover story. Thanks for writing.

 On lobsters and chemicals: In U.S. waters, the taking of egg-bearing lobsters is illegal. Such laws were enacted to let the lobsters reproduce, thus perpetuating the fishery.

This logic appears to have escaped some lobster catchers who take fertile females anyway.

Before inspectors examine the catch, the criminal fishers remove the sticky eggs from the mother’s shell. One common way to do this is to dip the animal in chlorine.

Such dips dissolve the hard-to-

remove glue that holds the eggs onto the female.

Now, researchers at Woods Hole (Mass.) Marine Biological Laboratory has figured a way to fight chemicals with chemicals. When lobsters that have been chlorined are dipped in a solution of potassium iodide, they turn yellow. This happens even 10 days after a chlorine dip.

Hopefully, cheaters will be prosecuted as a result of this new test.

 Dolphin deaths: Since the passage of dolphin-safe legislation in 1991, about 4,000 dolphins have been incidentally killed in tuna nets annually. This number is way down from the 52,000 killed in 1990 alone, but still, 4,000 each year is a lot of dead dolphins.

This “acceptable kill rate reinforces my belief that keeping dolphins in marine parks and research facilities is a good idea. If we are to save dolphins, people have to see some and researchers have to learn more about them.

The number of captive dolphins in the world is minuscule compared with the number killed. At least those in marine parks are safe from killer nets.

 Sea horses’ slaughter: Throughout China, sea horses are considered good medicine, particularly useful in aphrodisiacs.

Now, as a result of economic booms there and in other Asian countries, demand for the little fish is shrinking their populations at alarming rates.

Of the 20 million sea horses caught each year, some are sold for aquariums but most are dried for use as medicine, even though its effectiveness is unproven.

Sea horses are vulnerable to overfishing with their limited range in sea grass and mangrove areas. But there’s hope. Captive breeding has been started in at least eight countries.

 Oiled birds: Regarding my column on the large cost and small reward of washing oiled seabirds, Mike Talvola of Los Angeles writes via e-mail: “I am struck by the similarity to the ‘war on drugs’ that pours huge amounts of money … toward illegal drugs when at least some of that money directed toward nicotine and alcohol would probably result in much greater benefit.”

Scientists may unlock secrets of gian squid

Published February 10, 1997 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1997 Susan Scott

 IT’S amazing to me that enormous squid, 50 or 60 feet long, live here in the Pacific ocean, perhaps in our back yard, yet no one has seen one alive.

Now some light may be shed on these obscure animals. A group of researchers is traveling to the South Pacific to try to film giant squid in their home territory. The scientists will lower remote-controlled cameras, baited with squid food, to as deep as 10,000 feet.

If the effort is successful, the team will have cracked one of the biggest marine biology mysteries of all time: Where and how do giant squid live?

Myths and stories about these elusive deep-water creatures have been with us for centuries. Norwegian sailors called these big invertebrates kraken and others knew them as polyps (Greek for many-footed). But for most people, giant squid are simply sea monsters.

The image of a slimy skinned, 50-foot-long creature waving around 10 sucker-lined appendages does give me a little shiver. But the truth is, in spite of the stories of these “sea serpents” wrecking boats and grabbing people for lunch, no such attacks have been confirmed.

Besides that, it just doesn’t make sense that giant squid would be interested in eating humans. These animals live in the dark, cold depths of the ocean and healthy specimens never rise.

What do giant squid eat? Probably anything they can get their appendages around, most likely fish and other squid.

Squid appendages are unique. Most species, large and small, have 10. Eight of these appendages, called arms, are short and heavy, like those of their close relatives, octopuses. Like octopuses, cup-shaped suckers cover the inner flat surface of each arm in most species.

But the rims of squid suckers contain toothlike material and sometimes the inner walls bear hard hooks. These hooks, teeth and suckers help the creatures hold onto their slippery prey.

It is the hard parts of the giant squid’s suckers that leave scars on the skin of their main predators, the sperm whales.

Besides eight arms, most squid have two other appendages, called tentacles. Only the spatula-shaped tips of these long tentacles contain suction cups.

Squid tentacles are the business end of the animal, shooting out with tremendous speed to seize passing prey. The tentacles retract, drawing the food to the arms which hold it up to the creature’s mouth. There the squid tears the prey apart with strong jaws.

Capturing food in dark, sparsely populated ocean depths is difficult at best. But squids have superb eyesight. Also, they can instantly change color, have the ability to shoot out clouds of dark “ink,” and some species glow in the dark. All these strategies confuse prey.

They also fascinate people.

When I lean over the side of a boat at sea, I often wonder: What’s down there really, really deep?

Hopefully, we’ll soon find out.

Kaena Point is cleaner, safer than it was before

Published February 3, 1997 in the “Ocean Watch” column, Honolulu Star-Advertiser ©1997 Susan Scott

 Last week, I took some family members on a hike to Kaena Point. This was my first visit there since my car was trashed in the parking lot a year ago. Determined not to let paranoia spoil the walk, I removed everything from the car, left the doors unlocked and headed down the road.

My precautions were probably unnecessary because changes have occurred in this state park over the past year. Neat boulders line the parking lot and beginning of the trail, prominent signs forbid littering and motor vehicle riding, and the area looked cleaner than I had seen it.

Most important, the new Kaena Point ambassador, Reuben Mateo, was an obvious presence. When I met him, he was sitting near the entrance of the park greeting visitors in his state pickup.

I complimented him on the improvements. “I haven’t done much,” he said. “I’ve only been here two months.”

Still, the attendance of this friendly man with the big smile made all the difference. The message is that this jewel of a park is worth spending some money and effort to protect.

Mateo agreed that the number of vehicles in the park is still a problem. A future permit system may fix that.

But my family and I didn’t dwell on the noise and dust of the trucks and vans. We hiked past them in a brisk two-mile walk, then entered the nature park. There we enjoyed one of the best whale shows I’ve ever seen from shore.

Several groups of humpback whales were as active as they get. Two whales held their pectoral fins high out of the water as if “sailing” in the strong winds. Several others began tail-slapping. Others occasionally leaped from the water in spectacular breaches.

What a show it was, made even better by our having viewed the new IMAX film “Whales” the night before in Waikiki. “I’m so glad we saw that movie,” my sister said as we watched one whale slap its tail on the surface over and over. “Now I know what’s going on under the water too.”

The film, produced and partly written by former Waikiki Aquarium director Leighton Taylor, is well worth seeing. The footage of Hawaii’s humpbacks, both here and in their summer Alaska feeding grounds, is superb. The exciting coverage of right whales reminded me that there are other whales in the world to visit. Argentina’s Peninsula Valdez is now on my list of must-see places.

Kaena Point is a must-see place too, and not only for humpbacks. When we could finally tear our eyes from the sea, we discovered that other marine animals were practically sitting at our feet.

A group of Laysan albatrosses stood on a hill singing and dancing up a storm. We lowered our voices and kept our distance so as not to disturb them. Then along came a family with a big dog on the loose. We cringed, hoping it would not find and kill the albatross sitting on an egg near the path.

Such deaths will continue until people stop bringing unleashed dogs into the park.

I wished there was some way to shoo the courting albatrosses to the other side of the island. There, off Sea Life Park, private and public agencies have set up a little seabird paradise at Kaohikaipu Island.

On our way home, goat-like braying echoed from the cliffs above. These are the unusual calls of white-tailed tropic birds nesting on the mountainside. Despite years of looking, I have never seen one of these seabirds here.

This day was different. When I looked up, I spotted one of these lovely white birds flying toward the ocean.

“Now I understand why you like to hike so much,” my sister said when we returned to my untouched car. “With places like this around, walking is really fun.”

Walking to Kaena Point is fun. And with increased protection, it’s getting better all the time.