August 30, 2013

Turtle nest excavations are a big hit with visitors


On a hot and sunny morning in late August, a large crowd of about 75 men, women, children and even a few dogs huddled around a small beach enclosure, outlined with black tarpaulin, just south of Ramp 27 on Hatteras Island.

Just days before, more than 100 baby loggerhead sea turtles crawled along the same small stretch of sand as they made their mass exodus from nest to sea.  Unfortunately, some of their kin remained trapped within the nest.

But, the National Park Service excavated the nest -- to rescue any surviving hatchlings, document hatch success, and retrieve valuable data. And, the seashore staff members attracted scores of people looking to learn more about sea turtles and hoping to catch a glimpse of a much beloved sea creature.

Two National Park Service rangers oversaw the operation.  Kevin Chandler, who is often seen toting a large turtle shell around Coquina Beach, explained the excavation process and fielded questions from the audience, while James Yrigoyen, a biological science technician, kneeled in the sand as he dug, by hand, through the nest.

Yrigoyen worked swiftly, setting aside bits of eggshells and unattached eggs found within the nest, and, after only five minutes, he discovered a live baby loggerhead.

Folks snapped pictures with their cameras and inched even closer to Yrigoyen as he briefly displayed the palm-sized hatchling.  

“It is actually better if we don’t find any sea turtles in the nest,” said Chandler, surprising most of the observers.  “Part of that,” he explained, “is because they leave as a big group and their chance at survival is a little bit greater and, among other things, they’re still in this nest for a reason -- they either hatched late or are not as strong as the others.”

And their chances at survival are low to begin with.  “Close to only one in 10,000 are expected to reach sexual maturity,” says Yrigoyen.

As Yrigoyen continued to dig up the nest, Chandler provided detailed and colorful answers to questions that ranged in topic from general sea turtle information to specifics about the National Park Service’s research and the data obtained from excavations.

Chandler described the nesting process of adult female sea turtles and revealed that the number of eggs in a nest correlates with the size of the female and, at the same time, that the size of a turtle, which can reach up to 300 pounds, depends on its ability to find food.

When an observer asked about determining the sex of the hatchlings, Chandler explained that the temperature of the sand during the incubation period, not genetics, determines its sex.  Chandler also described several differences between the males and females, however, he directed further inquiries regarding mating and gender to the parents, who groaned in anticipation of an interesting car-ride home.

Once the nest was fully excavated, Yrigoyen had retrieved a total of 14 live hatchlings, five dead hatchlings, one turtle that died while hatching, and several unhatched eggs.  In total, the nest contained 145 eggs, 130 of which were empty by the time the Park Service excavated the site and it was, therefore, considered a very successful nest.

To ensure that all surviving hatchlings were rescued and correct data was collected, Yrigoyen examined each unhatched egg and those standing downwind quickly learned, or rather smelled, that several eggs had not fully developed.

Yrigoyen collected one egg for DNA research, but all other eggshells and matter removed from the nest was returned so that the natural cycle would remain intact and species, such as the ghost crab, could feed upon the remains.

At the end of the excavation, a few people took pictures with the rangers and asked further questions, while some families made plans to watch sea turtle documentaries.

The experience captivated both adults and children.

Madelyn Tyler, a 9-year-old from Virginia, has not studied sea turtles in school, but loves them and thought that the excavation was “pretty cool.”

For Cambria Anderson of Idaho and Kandice Butte of Tennessee, the experience exceeded their expectations.  Their children wanted to see sea turtles and they never imagined that they could outside of an aquarium.  “It was amazing, absolutely incredible,” reflected Butte.

And many who attended the excavation made plans to watch the park rangers release the 14 hatchlings later that night at Coquina Beach.  They felt lucky that they were able to witness both the excavation and the release of the surviving turtles.

The National Park Service opened the turtle nest excavations to the public this year with the idea that the program would provide a forum to talk to people and educate them about sea turtles.  It is an interactive program in a natural setting that allows folks to see marine activity and hopefully encourages them to protect the sea turtles, and other wildlife, in the future.

For those interested in attending a sea turtle nest excavation, call the excavation program hotline for specific details at (252) 475-9629.  Park rangers, roaming through the villages or on the beach, may also have information about impending excavations.

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