Tag Archives: Australia

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

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.

Nightmare on kid’s feet is critters’ big moment

Published September 2, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Lysianassoid amphipods, above, created an internet sensation when they nibbled on a teen’s feet in the waters at an Australian beach last month. The crustaceans known as sand fleas or sea lice are recyclers of the seas, usually choosing to feast upon dead plants and animals. Courtesy Wikimedia

Bloody attack! Mysterious sea creatures! A taste for human flesh! Unstoppable bleeding … And so went the sensational terms describing an injury sustained by a 16-year-old Australian boy last month.

Having sore leg muscles after a football game, Sam stood with his ankles in the water off a southern Australian beach. The 60-degree water numbed the teen’s skin, and when he emerged, blood oozed from multiple tiny bites.

When the teen’s father posted gory pictures of his son’s feet on Facebook, people got so overly excited you would have thought the kid got shredded by Freddie Kruger. In fact, the 16-year-old had pinprick lesions from a bunch of amphipods just doing their job.

Amphipods are crustaceans, an enormous group of shelled animals including shrimp, lobsters, crabs, barnacles and more. The ocean hosts 8,000 amphipod species with 2,000 more living in brackish and fresh water. Amphipod relatives are isopods and copepods, also with thousands of species each.

In biology, “pod” means feet, and the various prefixes above describe differences in the creatures’ limbs.

Although fleas and lice are insects, and amphipods are not, people often call amphipods sand fleas or sea lice.

The average amphipod is about a half-inch long. Some species, though, are barely visible to the naked eye, and one rare deep-sea species grows to 13 inches.

One of these huge amphipods, appropriately named gigantea, was found in the stomach of a black-footed albatross, one of Hawaii’s seabirds. Researchers believed the huge amphipod was already dead when the bird ate it. Check out this colossal crustacean at goo.gl/XdLhKF.

Most amphipods swim the world’s oceans eating dead plants and animals, making them outstanding recyclers. So, yes, amphipods eat animal flesh, but the creatures are neither parasites nor carnivores. Rather, most are omnivores, eating whatever they find, such as the Australian teen’s feet and ankles.

Sam’s immobility attracted his neighborhood amphipods, and since he couldn’t feel their nips in the cold water, he allowed them to keep biting.

Most amphipods use claw-tipped front legs to eat, cutting food off in tiny pieces and delivering it to the mouth. The creatures have no venom and are not medically dangerous. Had the parents elevated Sam’s feet and put a bit of pressure on the lesions, the bleeding would have stopped. But then the oceans’ sanitation engineers known as amphipods wouldn’t have had their 15 minutes of fame.

An Australian biologist identified the animals that munched on the boy’s feet as lysianassoid amphipods, a family that specializes in recycling. Some reporters, however, erroneously placed the creatures in the Kruger family of Elm Street.

Grotesque acorn worm helps clean sand in sea

Published August 19, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

An acorn worm leaves behind a mound of expelled sand that it has ingested while looking for organic matter. ©2017 Susan Scott

My nephew, Joe, pointed out an area of exposed sand during a low-tide walk in Australia.

“There sure is a lot of poop here,” he said.

“These piles aren’t poop,” I said, of the squiggly pyramids at our feet. “They’re sand cleaned by acorn worms.”

“What are acorn worms?”

“I would have to kill one to show you.”

I wasn’t joking. An acorn worm’s skin is so thin that when it’s full of sand, which is nearly always, the creature bursts open if you pick it up.

Besides, acorn worms aren’t exactly cute and cuddly. Each of the 70 or so species in the world’s oceans looks like a slimy piece of intestine with an acorn for a head and a neck that looks like a cervical collar, the brace people wear for neck injuries.

But even if these marine creatures won’t win any beauty contests, they’re tops in talent. The mushy housekeepers live under the surface from the shoreline to 10,000 feet, cleaning up the ocean’s organic wastes. The worms suck in sand, pick out and eat dead plant and animal material there and discharge the filtered sand in distinctive coils.

Hawaii’s acorn worms grow 1 to 18 inches long, the longer with a body diameter of 1 inch. North Carolina hosts the giant of the U.S., a worm that grows to 8 feet long and digs burrows nearly 10 feet long. The species ranges to Brazil.

An acorn worm’s rounded, muscular head does the digging. The collar serves as an anchor, and the body trails behind. Both head and collar contain glands that produce slick mucus that helps the worm slip through sand and mud.

   

Other glands make bromine, a chemical with a medicinal smell. This, along with the accumulation of iodine in the body, might protect the worm from infection and/or predators. Given that these slow-moving worms have no teeth or claws, chemicals are their only defense.

In Hawaii, Gould’s auger snail eats only acorn worms. The worm-eating livid cone snail preys on acorn worms.

An acorn worm has no brain, but some nerves. Sensory cells on the head can taste incoming particles. The mouth lies at the junction of the head and collar, and when the worm meets something inedible, it ducks its head into the collar. This closes the mouth like a plug in a drain.

The anus is where you’d expect, on the rear end.

As we walked among the endless acorn worm castings of Queensland’s Pancake Creek, Joe said, “The worms push the sand out from where?”

“From their anuses,” I said.

“Um, Aunt Susan? That’s what people call poop.”

Technically, he’s right. The mounds, called fecal casts, contain the worm’s feces. Still, those are minuscule compared with what was in the sand when the worm ingested it. Call the acorn worm’s sand coils what you will. Given my fondness for marine worms, I call them cool.

Peculiarity above water in Australia also amazes

Published June 17, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

I’ve been home from Australia nearly a week, and I’m still smiling over some of the comments locals there made about Hawaii.

One day we anchored Honu in a picturesque bay in the lee of Hummocky Island. Because it was late in the day, and it takes time and effort to inflate our rubber dinghy and attach its outboard, we jumped in the water and swam ashore for a snorkeling excursion and beach walk.

About an hour or so after swimming back to the boat, our distant boat neighbors motored toward us in their dinghy. When the Australian couple saw our home port, Honolulu, on the transom, they called out, “Hello! We came over to see what crazies were swimming in shark-infested waters. Now we see. You’re from Hawaii!”

They sped away, leaving us puzzled. Did they think that Hawaii residents are braver than Australians? Or that we foreigners don’t understand the risk? Or that Hawaii residents are foolhardy? We never found out.

Nor could we find information anywhere that Hummocky Island is more “shark infested” than anywhere else in Great Barrier Reef waters, or in Hawaii.

On average, three people die from shark attacks in Australia annually. Given the number of people in the water, the chances of an attack are so minuscule I never even think about it.

No sharks showed up on this trip, but we could not shake the sharp teeth of politics.

While checking Honu into a marina during stormy weather, I slid her official certificate over the counter. In big, bold capital letters, the heading says, “UNITED STATES OF AMERICA.”

“Sorry,” the manager said, pushing the paper back. “We’ve stopped accepting these.”

I was speechless. This vessel documentation is as official as it gets. No other boat papers exist.

“Relax,” the manager laughed. “I’m just kidding you. But, really, what were you thinking, electing that clown?”

How does one answer such a question? “We’re from Hawaii,” I said. “It wasn’t us.”

“Hawaii! OK, then. You can stay.”

That guy was joking, but a young convenience store clerk was dead serious.

“I always wanted to go to Hawaii,” she said, “but I saw a TV show on tsunamis and now, forget it, I’ll never go there.”

Rendered speechless again.

The friendly woman at Townsville’s Breakwater Marina, where we left Honu, gave us a farewell that made us laugh.

“Have a good trip back to America,” she said as we finished up the paperwork. “Sorry! I mean Hawaii.”

And finally, as I folded up the last of Honu’s laundry and said goodbye to another marina worker, she said, “You’re not leaving us?”

“Yes. I love Australia, but I love my home in Hawaii, too,” I said. “I’m going from one good place to another.”

“Fair dinkum,” she said.

Spring tides are perfect for strolling among reef

Published May 27, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A shrimp at low tide off Australia’s Great Barrier Reef Marine Park waits for a spring tide to return and carry it away. ©2017 Susan Scott

BRAMPTON ISLAND, GREAT BARRIER REEF MARINE PARK >> For the past few days, I’ve been choosing walking over snorkeling. That might seem a poor choice given where we’re sailing. This week, however, the new moon has brought spring tides, and here off the Queensland town of Mackay, that means a 15-foot difference between the high and low. So when the tide is out, the reefs are, too.

Spring tides have nothing to do with springtime. The name comes from a centuries-old notion that during new and full moons, the water “springs” up. Here where we’ve anchored Honu, the incoming tide seemed to leap rather than spring, covering the places we walked yesterday afternoon with 15 feet of water. We must wait until this afternoon, when the tide drops to its new-moon low, to stroll with the seabirds on the exposed reef.

It sounds awful to be walking on a reef, but we aren’t. We step in sand lanes that the currents have deposited between coral heads, seaweed tufts and rocky spires. In the late afternoon sun, the smooth, water-carved sand whorls remind me of paintings by Georgia O’Keefe.

Puddles and pools remain in the lowest reef flat depressions, where fish, crabs, shrimp, snails, sea cucumbers and countless other creatures lie motionless, waiting for the tide to turn. Those left high and dry, such as giant clams, anemones and coral polyps, close up tight during their dry time.

Because spring tides occur twice a month, the animals clearly have their ways of surviving in air for hours at a time. Even so, given all the damage we humans have done to animals and their habitats, I like to offer a helping hand to my friends.

During our reef walks Craig waits patiently while I carry starfish from dry sand to water-filled depressions left by awesomely huge stingrays. We saw one of these crater makers from the dinghy on our way to the beach and judged it to be about 4 feet wide.

Craig helps with photos too, reducing ripples on the water’s surface by standing heel to heel upwind of a stunning red-orange shrimp in about 3 inches of water.

In spite of four monster feet near its burrow, the shrimp remained motionless for the photo shoot. With its brilliant colors, it seems that hiding would be a better survival strategy than holding still. Then again, movement might give away the shrimp’s position to the stone curlews, oyster catchers, sea eagles and gulls scouting the flats for food.

When sailing among the hundreds of islands in the Great Barrier Reef Marine Park, there are no activities I would choose over snorkeling or diving. Except during spring tides. Then, with pleasure, I choose walking.

Platypuses add to thrill of wildlife sightings

Published May 20, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A platypus, a mammal of rather ordinary stature with a ducklike bill, is seen at a national park in Queensland, Australia. ©2017 Susan Scott

GREAT KEPPEL ISLAND, QUEENSLAND, AUSTRALIA >> “It’s so small.” That was our group’s first impression of the platypus we saw paddling along the surface of a creek in Carnarvon National Park. When an animal is as celebrated as the platypus, people expect something bigger than a chihuahua.

The weather had continued its stormy streak, making sailing Honu unappealing. But in Australia, to-die-for wildlife is always close by. We rented a car, drove to the national park and were soon hiking with kangaroos and wallabies, laughing with kookaburras and cockatoos, and gasping at a sugar glider’s aerial show. And even though they aren’t marine, three platypuses kindly showed up to give us an aquatic thrill.

Platypuses are freshwater animals that spend their days snoozing in riverside burrows. At dusk the creatures emerge to forage for insects, shrimp, tadpoles, mussels and snails in the streambed. In zoos, keepers often feed their platypuses yabbies, which I now know are freshwater crayfish.

Platypuses have been famous in biology lore since 1799 when an official in Australia sent a hide of the animal to Great Britain.

Scientists there thought that some jokester had sewn a duck bill to a beaver body.

The platypus bill so resembles a duck’s bill that a common name for the animal is duck-billed platypus, even though no other platypus species exits.

Nor is the bill a bill. It’s a single, flat leathery organ containing nerves that detect electrical fields generated by living prey. Sharks and electric eels also use electroreception to find food, but the platypus is one of the only mammals with that ability.

Speaking of mammals, that’s another platypus claim to fame. These little 4- to 6-pound creatures lay eggs and then nurse their hatchlings.

After mating, the female produces two eggs, which she incubates inside her body for about 28 days. Once laid, the mother curls her tail, a fat storage structure, around the eggs for another 10 days. Hatched platypus babies suck milk from two mammary patches (no nipples) on their mother’s belly.

Upon returning to Honu from our adventure inland, the wind lay down, the sun shone brightly and off we sailed to the Keppel Islands, popular anchorages in the Great Barrier Reef Marine Park. On the voyage another nonmarine species awed us all day long. Streams of exquisite blue-and-brown butterflies called blue tigers passed through Honu’s rigging while migrating from the mainland to the islands of the Great Barrier Reef.

As I write, it’s pouring rain again, but who cares? I’m in Australia.

Australian snakes keep residents on steady alert

Published May 6, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

A lace monitor lizard tasting the writer’s toes at Aircraft Beach, Eurimbula National Park. ©2017 Susan Scott

Pancake Creek, Queensland >> Australia has a national phobia about snakes.

We started our latest Australian adventure by sailing to this national park estuary that has no access by road. At Pancake Creek the beaches are huge (one is called Aircraft Beach because small planes can land there), the wildlife abundant (soldier crabs, stone curlews, friendly monitor lizards), and the hiking possibilities are nearly endless.

Pancake Creek is Australian wilderness at its best, so good I feel lucky to once again be visiting this magnificent country. So what’s the first thing several locals said when I told them we were sailing here? “Watch out for snikes.” (They mean snakes.)

The Pancake Creek region has no more snakes than anywhere else in the country, but OK, I’ll give Aussies the fact that most of the world’s venomous snakes are found in Australia. Of the country’s 172 species, 115 are venomous.

Most of the world’s pythons are Australian, the longest being the scrub python at 23 feet, as long as a two-story building is tall. I have a book aboard Honu with an amazing picture of an olive python — only about 16 feet long but bulkier than a scrub python — trying to haul a drowned wallaroo up a cliff for a meal.

In the Darwin area, homeowners have to protect their dogs, chickens and cats from olive pythons that squeeze the pets until they stop breathing, and then swallow them.

During dry spells some snakes seek out water and have been found bathing in residents’ toilets. One 7-foot-long snake worked its way through an overhead light fixture in an apartment bathroom. Roommates walked in to find the snake dangling, giving them an updated version of the “Psycho” shower scene.

My favorite Australian snake story happened in 2013 when a passenger aboard a Qantas flight pointed out a snake on the wing to a flight attendant. The scrub python bravely held on for the entire hour-and-50-minute flight. People rooted for the plucky animal, but the wind and cold were too much for it,and, sadly, the hitchhiking python died.

All snakes have forked tongues that they flick in and out to taste or smell potential food. Only Australia’s goanna lizards, called monitor lizards in other countries, share this forked tongue trait with snakes. (Goanna is the Australian version of the word iguana, a group of lizards from the Americas unrelated to monitor lizards.)

So far, we’ve encountered no snakes while hiking around Pancake Creek, but I did manage to hold still in a picnic area while a goanna (lace monitor lizard) flicked its forked tongue over my toes.

In the meantime, we Americans are looking forward to meeting some Australian snikes.

Australian yabbies draw fishers and stingrays

Published April 29, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Freshwater crayfish, or yabbies as they are called in Australia, serve as bait for fishermen. Yabbies are also delectable to stingrays, which smash the burrowed tunnels the yabbies live in, and also to the fish that follow the stingrays. ©2017 Susan Scott

BUNDABERG PORT MARINA, QUEENSLAND, AUSTRALIA >> I’m back in Australia getting our sailboat Honu ready for another Great Barrier Reef adventure.

To answer a common question, no, we do not sail Honu back and forth between Hawaii and here. At Honu’s average speed of 5 miles per hour, it would take 50 days, minimum, to sail the 6,000 miles between Hawaii and Australia. It’s a long, hard voyage that for us is unfeasible, timewise. So, for now, the boat stays Down Under.

That means, of course, Honu is subject to cyclones. To answer another question, Cyclone Debbie did not strike this marina, and Honu survived the torrential rains unscathed.

Because Australia has marine life I don’t know, customs I’ve not seen and language I don’t always understand, during my trips here I have my own endless questions. A recent one was: Why are people sticking hand-pump suction tools into the sand at low tide?

When I asked a friendly angler, he said, “I’m pulling up yabbies.”

I’ve been in Australia enough to know that yabby is another name for edible freshwater crayfish. (Spiny and slipper lobsters are also called crayfish here.) The beach, however, was on the ocean and the suction pipe was small.

“To eat?” I said.

“No, for bait. Look here.”

He stabbed the wet sand, pulled back the plunger and came up with a cream-colored, soft-bodied creature about 3 inches long. “There’s a yabby,” he said, handing it to me. “That big claw means it’s a male. Careful, it can give you a sharp nip.”

It looked like a shrimp to me, but then that’s the problem with common names. (Latin names have their own issues — call a yabby a Callianassa australiensis and the conversation is over.)

Australia’s bait yabbies are found along its east coast where they live in the sand between the high and low tide lines. At low tide, fishers dig near telltale holes in the sand, but that’s no guarantee the creature is there. Each adult yabby has three or four holes joining its main burrow, which can be 2 feet down.

Another question I’ve had for years in Australia is why the sand on some beaches during low tide is pocked with dozens, sometimes hundreds, of perfect stingray outlines including their long tails.

It’s yabbies again. During high tide, the rays swim over the sand flats and “puddle” the sand with strong beats of their powerful pectoral flaps. This collapses yabby burrows, bringing the now-homeless creatures to the sand’s surface. Besides being meals for the rays, the uprooted yabbies also get eaten by fish freeloaders that have followed the rays.

Every time I take a walk here in Australia, I end up with so many wildlife questions, I have to write them down. And I’m still in the marina.