Honolulu Star-Advertiser © Susan Scott
May 4, 2009
People often ask me how I think up things to write about week after week, year after year. It’s easy.
Besides the ocean having a nearly infinite number of subjects, I’ve got mail.
“I found a baby plover,” e-mailed an Oahu reader last week. “What do they eat? Who can I call to rescue the chick?”
The time and place told me this orphan was not a plover. Hawaii’s golden plovers lay one clutch of four eggs each year from late May to mid-June in Alaska. A few of Hawaii’s plovers spend summers here if they’re injured or underweight, but these migratory shorebirds never raise chicks in the Islands.
The baby bird, it turned out, was a dove. The writer found help at Honolulu’s Wild Bird Rehab Haven. For information see www.wildbirdrehabhaven.org.
Seven-year-old reader Danielle writes, “Um, do turtles shed their shells?” Danielle’s friend has a turtle and claims it “shedded” its shell. Danielle wants to know if this could be true.
No, it’s not true. A turtle’s shell is a permanent part of its body attached to flesh and bones inside. The shell grows with the rest of the body.
A snail’s shell also gets bigger as the snail inside grows.
An empty turtle or snail shell means the animal died and then bacteria and other animals ate the flesh. Sometimes other recyclers use empty snail shells. Hermit crabs must find, and move into, bigger and bigger shells as they grow.
Crabs, shrimp and lobsters shed their shells in growing stages called molts. When the animal gets too big for its shell, the creature reabsorbs much of the calcium from its shell, puffs itself up with water and backs out of its too-tight “coat.” A new shell then hardens around the inflated body. When the animal releases the extra body water, the flesh has room to grow inside the larger shell.
Sea snakes are super-shedders, getting rid of their entire skins every two to six weeks. The shed starts at the head with the snake rubbing its mouth against a solid object. The snake then snags the loosened head skin on a protrusion and literally swims its skin off, leaving it inside out.
Researchers believe sea snakes shed skin so often to get rid of marine growth. Barnacles and other fouling organisms often attach themselves to sea snakes’ tails, and fuzzy seaweed can cover a sea snake’s entire body. Because these reptiles get 20 percent of their oxygen through the skin, fouling organisms can be fatal.
Regarding a sea snake, a Maui reader e-mailed that in 2007 she and her two sisters saw a black snakelike thing around some rocks near a beach on the southeast part of the island. When she came across one of my past columns that said yellow-bellied sea snakes have black backs, she realized what they saw. “I must say,” she wrote, “that I now stay out of the water.”
It’s a shame anyone would stay out of Hawaii’s waters because of sea snakes. These reptiles are extremely rare here and don’t give a hoot about people. If left alone, sea snakes swim past swimmers and divers without even a glance.
I love my mail, which gives me questions to answer and comments to ponder. I also get inspired when I find marine animals unfamiliar to me. That’s why, as you read this, I’ll be sailing across the Sea of Cortez — collecting column material, of course.