Tag Archives: Brampton Island

Ocean ‘jewels’ encompass life stories of amazing snails

Published June 3, 2017 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2017 Susan Scott

Snail species, or gastropods, are abundant in the waters off Australia. The shell at upper right is from a Conus geographus, a cone snail that can kill a person with its sting. However, the sand-filled shell was indicative that the snail inside was long dead and, therefore, was safe to pick up. ©2017 Susan Scott

BRAMPTON ISLAND, QUEENSLAND, AUSTRALIA >> The combination of afternoon low tides and Cyclone Debbie’s recent stirring up of the ocean floor has sparked a new passion in me: snails.

Like all beach walkers, I’ve always enjoyed finding pretty seashells, and like all biologists, I learned about the animals called mollusks. But never have I seen snails and homes like I have this week.

Australian waters host countless snail species. Really countless. One local book claims that more than 10,000 species live here. Another shell guide reports tens of thousands.

Marine mollusks include octopuses, cuttlefish, squids and sea slugs, but those shell-less creatures don’t leave much of a legacy after they die. What gets us beachcombers excited is finding the jewel-like homes of two-shelled creatures we call clams and oysters (bivalves), and the one-shelled creatures we know as snails (gastropods).

Most people don’t include the word “snail” when talking about a shell they’ve found, but that overlooks the animal that built the stunning piece. Of the billions of empty shells cast ashore on the world’s beaches, each has its own life story.

Most snails begin their lives as tiny hatchlings that swim for days or months before settling on the ocean floor. Soon after, the baby snail’s glands secrete a hard, calcium carbonate covering, the beginning of the adult animal’s shell, around its soft body. As the animal grows, its glands enlarge the shell along its outer edge, often in a spiral.

A snail doesn’t add shell material evenly, but rather lays it down in precise places to create its own species’ shape, thickness, height and diameter. At the same time, the creature’s glands introduce pigments into the calcium carbonate that show up on the shell as spots, lines or other markings unique to the species.

Snails don’t enlarge their shells continuously, but do it in spurts. On some spiral shells you can see growth lines called sutures. In adult snails the inside whorls of broken shells reveal the snail’s nursery and its rooms during adolescence.

Besides being superb architects and sculptors, snails are math geniuses. The complex calculations of depositing each molecule of shell and each speck of color in the precise right place at the precise right time to create a species’ exclusive shell is unfathomable.

During a stretch of bad weather, we parked Honu in a marina, rented a car and drove to central Queensland to see Australia’s sapphire gem fields. The sapphires in the shops were OK, but I didn’t buy any. I prefer jewels made by snails.

Kangaroos are surprisingly excellent ocean swimmers

Published October 12, 2015 in the “Ocean Watch” column, Honolulu Star-Advertiser ©2015 Susan Scott

A baby kangaroo, or joey, fits comfortably in writer Susan Scott’s hand. ©2015 Susan Scott

A baby kangaroo, or joey, fits comfortably in writer Susan Scott’s hand. ©2015 Susan Scott

BUNDABERG, Australia >> Today is my first day back on my sailboat, Honu, moored here in the Bundaberg Port Marina. Bundaberg is a town in Queensland, the state famous for its offshore neighbor, the Great Barrier Reef.

I say offshore because the closest atoll from this marina to Great Barrier Reef National Park is 50 miles, and in some places the islands and reefs are 100 miles out. If the weather permits and my boat systems work, I plan to sail to the closest atoll, Lady Musgrave. But even if I stay in the marina to wait out strong winds or make repairs, I’ll be having a good time with one of my favorite marine animals: kangaroos.

OK, kangaroos aren’t marine animals. But during past visits to Australia, I’ve had outstanding experiences with these creatures on islands, in beach parks and at shore-side wildlife facilities. Several years ago I sailed solo to Brampton Island, one of the 300 or so islands in the Great Barrier Reef. After anchoring, I rowed my dinghy ashore and headed off on a hike. The island was having a butterfly bloom at the time, and as I stood spellbound in a blizzard of blue wings, the ground began to shake. Earthquake! I thought, heart pounding. Tsunami!

My panic didn’t last long, though, because a moment later, hopping down the trail like a bunch of mutant bunnies, was a family of eastern gray kangaroos.

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Kangaroos can’t walk backward, so when the dominant male (called a boomer), saw me, he made a wide U-turn. His family followed, and off they bounced, creating another trail tremor.

The eastern gray kangaroo is a heavyweight, not as tall as the red species, but weighting about the same, up to 200 pounds for males, 100 for females.

People didn’t bring these kangaroos to the island. Surprisingly, kangaroos are excellent swimmers and do just fine in the ocean, even maneuvering around stand-up paddlers: bit.ly/1PdBV2T.

Another time here, I visited a beach-side trailer park known for kind residents rescuing orphaned roos when their mothers are hit by cars. To escape early-evening mosquitoes, the kangaroos there hop to the beach and stand in the water. Afterward the animals spring back to their human friends for dinner, served in dog dishes at the door of each person’s home.

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Last year I visited a private wildlife facility and arrived to find a worker bottle-feeding a baby kangaroo. That nice woman had no idea what a joyous moment she gave me when she handed the joey to me and let me feed it.

Now I’m back in Australia looking for more roo delights. I don’t have to look far. Kangaroos might not be marine animals, but (thank you!) they routinely visit this marina.

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

©2015 Susan Scott