AF biologists observe, protect sea turtle nesting habitats

  • Published
  • By Eric M. Grill
  • Air Force Civil Engineer Center Public Affairs
JOINT BASE SAN ANTONIO-LACKLAND, Texas --  With the annual sea turtle egg-hatching peak season beginning, biologists at Air Force bases in Florida are closely monitoring the nesting habitats of several different species of sea turtles on their installations' beach fronts.

Sea turtles, inhabiting coastal U.S. waters, are protected under the Endangered Species Act of 1973. Although sea turtles live most of their lives in the ocean, adult females return to beaches to lay their eggs. They often migrate long distances between foraging grounds and nesting beaches.

Female sea turtles excavate pits using their fore and rear flippers to remove the upper layer of dry sand, said Julie Jeter, Air Force Civil Engineer Center wildlife biologist here. Using their rear flippers to dig egg chambers in moist sand, the females lay 100 to 126 ping-pong ball-sized eggs per nest. Afterwards, they finish the nests by covering the eggs with sand and return to the water.

After hatching, the young may take as long as a week to dig themselves out of the nest, said Jeter, who helps oversee the Air Force's conservation efforts. The hatchlings emerge at night and move toward the ocean using low-lying light, like the moon's reflection off the ocean's waters.

The nests and hatchlings however are an easy source of food for predatory animals by native and nonnative species on almost all nesting beaches. Of the eggs that hatch, one out of 1,000 sea turtle hatchlings will make it to adulthood. If they make it to adulthood, the average sea turtle lives up to 80 years.

At Tyndall Air Force Base, where the Loggerhead, Leatherback and Green sea turtles are prevalent, biologists observe and protect nests on 18-miles of beach front.

"The barrier islands (located on Tyndall's coast) are a good buffer for the mainland of Tyndall where the main military mission occurs," said Wendy Jones, Tyndall's wildlife biologist with the 325th Civil Engineer Squadron's Natural Resources branch. "Because we don't have active military missions out there, it's become a habitat for the endangered sea turtles as the majority of the surrounding beach front was developed."

Biologists look for crawls, or flipper tracks left behind on the beach, to locate the sea turtle nests.

"When we find the crawl and nests, we then screen, flag and monitor the sights for the 60 days or so before hatching begins," Jones said.

Protecting sea turtle eggs sometimes means having to move nests to keep them safe from predatory animals or human interference.

"We relocate nests as necessary to give the eggs a better chance for hatching," said Bruce Hagedorn, supervisory biologist with the 96th Civil Engineer Group at Eglin Air Force Base.

Eglin has 20 miles of beach front where the Loggerhead sea turtle lays eggs.

"We try to mimic the natural habitat of the original nest," Hagedorn said. "It's better to have them survive and make it back into the water."

At night, both adult female sea turtles and hatchling sea turtles are disturbed by artificial light, including street lights, flashlights, flash cameras and even campfires, Jeter said. Visual cues from natural light sources are important for sea turtles to navigate back to the sea after nesting or hatching.

Regulating artificial light on beach fronts help hatchlings survive, she said. The U.S. Fish and Wildlife Service and National Marine Fisheries Service recommend shielding of light sources, screening with vegetation, placing lights at lower elevations and using limited spectrum low wavelength lighting (such as low pressure sodium vapor lights) as possible solutions to beach lighting problems.

"Artificial light confuses the hatchlings and they sometimes head toward urban areas," Jeter said. "Sea Turtle Recovery Plans provide guidance regulating artificial lighting leading to less light pollution on the beach fronts."

The sea turtle hatching season runs from August to October.