Island sees record number of sea turtle nests – Coastal Observer

Island sees record number of sea turtle nests – Coastal Observer

Pawleys Island has set a new sea turtle nesting record for the second consecutive year with 45 nests, up from to 39 last year. And more are expected as the nesting season continues. Nearby beaches haven’t seen the same surge. As of this week, North Litchfield has recorded five nests, Litchfield by the Sea has four, Litchfield Beach has 12 and Huntington Beach State Park has 18. “There’s no answer for that,” said Mary Schneider, the Pawleys Island coordinator for the S.C. United Turtle Enthusiasts, better known as SCUTE. “That’s the $50 million question,” said Brian Shamblin, associate research scientist at the University of Georgia who has studied sea turtle nesting habits.  SCUTE has been collecting maternal DNA from sea turtle nests since 2010 in order to track the nesting females and study their habits. That project tracks turtles from St. Augustine, Fla., through the Carolinas.  Female turtles typically go back to the area where they hatched to lay eggs, but it may not be the only reason, Shamblin said. “That’s true to some degree,” he said. “It’s something that we’re trying to learn more about. There seems to be a lot of individual variation in that.” Shamblin said he has tracked turtles that were hatched in Florida lay nests at Cape Lookout, N.C. “For some of them, it’s like they didn’t go back home. They imprinted on these new areas and then they started nesting in those areas,” he said. Researchers have also begun to collect paternal DNA over the concern that rising temperatures are reducing the number of male sea turtles and threatening the species’ future. The temperature of the nest determines the sex of the hatchings. Higher temperatures produce more females. “It’s still very early. We don’t really have answers yet,” Shamblin said. It wasn’t until a couple years ago that Shamblin figured out that the membrane that surrounds the yolk can help researchers learn about the males that a female turtle has mated with. “We’re just trying to understand what that looks like, especially now for the males. Unless they’re sick or they get hit by a boat or something, you’re never going to see the males come on land,” Shamblin said. “This is kind of a way that we can track the males from the beach.” It takes a few days to process data that comes in to his lab. Shamblin typically has six to 10 students working at a time. More than 100 students have worked on the maternal DNA project over the last 16 years. Broken eggs are preferred for DNA samples, but volunteers who collect them will sometimes sacrifice an egg from the nest. Collecting paternal DNA includes clipping half an inch off of a dead hatchling’s flipper. It isn’t unusual to find dead hatchlings or broken shells when volunteers conduct nest inventories. Those who have a letter of authorization from the state Department of Natural Resources to handle the turtles, including Schneider, collect the samples by rolling the eggs and fins up and placing them inside of a vial of alcohol.  Shamblin expects to have analyzed 1,000 samples by the end of turtle season. “It comes down to the folks that are actually on the beach, doing all the surveys and keeping everything going,” he said. The DNA is extracted by a Natural Resources staff member and logged into the Northern Recovery Unit Genetic Capture-Recapture database at seaturtle.org before the samples are shipped to Shamblin for analysis.  Each turtle is assigned a unique identification number and entered into databases. A female may lay several nests with more than 100 eggs in each up until mid-August. There have been nearly 31,000 live hatchlings released from Pawleys Island since 2010. SCUTE began recording nests in 1990, according to Schneider. They were lucky to find 10 nests per season, she added. SCUTE divides the island into four sections for its patrols. Three of the most recent nests were laid in the middle of the island, another between Hazard Street and the south end parking lot and one on the north end.  A majority of nests are found on the “quiet parts” of the island, Schneider said, which she thinks is a factor in why nesting turtles have favored Pawleys Island this season. “Fewer lights and fewer people,” she said. South Carolina recorded its first sea turtle nests on May 6 near Charleston. Georgetown County’s first nest was just a few weeks later at DeBordieu. Through June, SCUTE had recorded an increase of 116 nests over last year from North Island to North Myrtle Beach. “That means we will have a very, very, very busy hatching season,” Schneider said.