Currents: science and conservation
Nesting sea turtles enjoy banner year
by Abi Nicholas
The Post and Courier
A loggerhead makes her way back to the ocean after nesting on Folly Beach last year.
Number of nests, hatching success rates climb in 2008
Three Folly Beach Turtle Watch volunteers gather around a blocked-off section of sand near the dunes at The Washout on Folly Beach. Orange tape and wooden stakes, along with a pumpkin-colored sign that reads “Loggerhead Turtle Nesting Area,” mark where, in late July, a female loggerhead laid her eggs.
It’s now mid-September. The eggs have hatched, and three days ago, some of the hatchlings scurried to the sea; the volunteers want to know just how many successfully completed their journey.
They start digging, scooping out handfuls of soft, tattered eggshells — and a few that look like perfect ping-pong balls — from a hole about 18 inches deep.
Of the 122 white, round eggs that were laid in the nest, only nine remain unhatched.
“This is great, a great nest,” says Judi Beahn, the volunteer program coordinator for Folly Beach Turtle Watch.
Abi Nicholas/Tideline Magazine
Bob Neville, volunteer with Folly Beach Turtle Watch
Abi Nicholas/Tideline Magazine
And so the season went: loggerheads nesting in record numbers and eggs hatching with incredible success rates. After a decades-long trend of declining nesting numbers, state sea turtle experts and volunteers are surprised and delighted to report that this was one of the state’s best nesting seasons since 1980, when the South Carolina Department of Natural Resources started keeping data.
By the end of August, when the last eggs were laid, South Carolina reported 3,119 loggerhead nests, up from 1,716 the year before and 2,568 in 2006.
As far as hatchlings go, Beahn says the Folly Beach nests averaged about a 77-percent success rate; nests in the past three to four years saw only about 50 percent to 60 percent of their eggs hatch, she says.
She’s not sure why, but Beahn thinks one reason the 2008 nesting season was so successful on Folly Beach was the strong community support. Aside from the 30 or so volunteers, “the mayor has been a strong supporter of the group and has done a lot of work with South Carolina Electric and Gas to get street lights shielded, informational letters sent to homes and enforcing lightingordinances,” she says.
The declining number of shrimp boats trawling the waters might also have some- thing to do with the increase in sea turtle nests this year, according to an Associated Press report.
Regardless, experts are reluctant to say that this is the start of a new trend; some even suggest that the currently threatened loggerhead could be labelled an endangered species by early 2009. Despite a stellar sea- son, threats still abound for loggerhead sea turtles.
Beahn notes problems this year with people digging deep holes and not filling them in.
“One turtle fell into a hole earlier in the sea- son,” she says. “She pulled herself out, but she exerted so much energy, which she needs to dig her nest and lay her eggs.”
Beach-goers also often leave trash, towels, beach chairs and other items behind when they leave the beach, Beahn says. Loggerhead sea turtles are fickle about nesting conditions.
If the water is too hot or too cold, they won’t mate. If it’s too bright or loud on the beach, they might not lay their eggs. And if they run into an obstacle — like an abandoned beach chair — they’re likely to turn right around and wait until next year.
And of course, natural predators such as sand crabs, raccoons and ants are a constant risk to sea turtle eggs and hatchlings trying to make their way to the surf.
“There will always be threats, things we’ll try to protect the turtles from,” Beahn says, “but this was a good year. Probably the best year Folly Beach has seen.”
Folly Beach logged 63 loggerhead nests this season; the highest number previously re- corded was 60 nests in 1999.
Folly Beach also had a rare leatherback nest, one of five in South Carolina this season, the highest on record for a single year, according to SCDNR. The other leatherback nests were recorded on Kiawah, Bull and Cape islands, and in Garden City.
Reach staff writer Abi Nicholas at 958-7375 or abi@tidelinemagazine.com.
LOGGERHEAD SEA TURTLE
Matt Winter/Tideline Magazine
A loggerhead relaxes in a bed of sargassum about 20 miles offshore Charleston.
SCIENTIFIC NAME: Caretta caretta
LOGGERHEAD BASICS: Adult and juvenile loggerheads have rich reddish-brown carapaces and yellow plastrons. Hatchlings lack the reddish tinge and vary from light to dark brown dorsally. A large skull is conducive for strong jaw muscles, used for crushing conchs and crabs.
Adult loggerheads in the southeastern United States have a mean length of 36.2 inches and weigh about 249 pounds. Hatchlings measure about 1.8 inches long and weigh about 0.7 ounces.
STATUS: The loggerhead is federally listed as threatened.
MIGRATION: During the winter, loggerheads usually leave the cold coastal waters and head toward the western edge of the Gulf Stream.
NESTING: The southeastern United States is the major nesting area for loggerheads in the western Atlantic. The primary nesting beaches in South Carolina are between North Inlet and Price’s Inlet. Of the 188.3 miles of coastline in the state, about 70 percent is suitable nesting habitat. Nesting season runs from mid-May to mid-August. Average clutch size in South Carolina is 120 eggs, with an average incubation period of 55 to 60 days. The log- gerhead, the official reptile of South Carolina, is the most common sea turtle to strand in the state, though nesting population has declined 3 percent per year since records began in 1980.
Source: SCDNR Marine Turtle Conservation Program
Matt Winter/TIDELINE
Beached whales suffered illnesses
The Post and Courier
A 10-foot pygmy that washed ashore Aug. 22 at Folly Beach was poorly nourished and “heavily parasitized.
Hemorrhaging, congested lungs and a parasite infestation were found in a mal- nourished 11½ -foot pygmy sperm whale that washed ashore Aug. 31 at Isle of Palms, a marine scientist said.
It was the latest in a spate of pygmy sperm whale strandings that have ocean researchers puzzled. Nine have happened recently from Florida to North Carolina, including one at Folly Beach on Aug. 22.
“We’re trying to find out what’s going on because we can’t determine it right now. We don’t know. It’s a big mystery at this point,” said Wayne McFee, a marine biologist with the National Ocean Service in Charleston.
The strandings are significant because they could provide clues about the ocean’s health, he said.
A serious heart disease known as car- diomyopathy has been found in about half of stranded pygmy whales. Meningitis has been discovered in some. But there is nothing that points to an epidemic of viral or bacterial infections, he said.
A 10-foot pygmy that washed ashore Aug. 22 at Folly Beach was poorly nourished and “heavily parasitized.” Tissue samples from the Isle of Palms and Folly Beach whales’ organs have been sent to a lab for analysis, McFee said.
Fully recovered, ‘Little Jetty’ heads back to sea
Diane Knich/The Post and Courier
S.C. Aquarium biologist Kelly Thorvalson releases Little Jetty.
Little Jetty, a juvenile Kemp’s ridley sea turtle, was released Sept. 13 on the Isle of Palms after spending nearly three months at the S.C. Aquarium’s Turtle Hospital.
The 3.3-pound turtle swallowed a fishing hook after a recreation fisherman reeled him in near the Charleston Harbor jetties in late June.
The turtle initially had endoscopic surgery to remove the deeply embedded hook from its esophagus, only to experience complications from trauma and anesthesia afterward. Sea Turtle Rescue Program staff had to resuscitate the turtle many times using oxygen and medications.
A crowd of about 300 people gathered to watch Little Jetty’s release, probably the only time most will see a Kemp’s ridley sea turtle on Charleston’s shores.
The rare endangered turtle feeds off the South Carolina coast but never sets a flipper on its sand, aquarium veterinarian Shane Boylan said. The turtles nest mostly in Mexico and the Caribbean.
When the time came for Little Jetty to embark on his journey out to sea, Boylan said he was “completely healed, A-OK.”
Source: The Post and Courier
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