Oceana Newsletter Fall 2009: Nesting Nights
by Emily Fisher
Last September, I was lucky enough to witness loggerhead sea turtles hatch on Bald Head Island, NC. This year, Oceana marine scientist Kerri Lynn Miller joined me during sea turtle nesting season in mid-June. We were determined to see one of the most spellbinding rituals in the natural world.
2008 was a record-setting year on the island, with more than 100 sea turtle nests, well above the average 60 to 70 nests. But by the time Kerri Lynn and I arrived, turtles had laid just 12 nests and the staff at the Bald Head Island Conservancy (BHIC), our liaison on the island, had seen 13 false crawls. A false crawl, which is common among loggerheads, is when a female comes ashore but returns to the water without laying her eggs because she’s spooked by any number of factors, including predators, white lights, or beach chairs.
Loggerheads nest every two or three years, so there is variation in nesting numbers from year to year, but human intervention is also at play this year. As the channel near the island is widened by dredging, nesting beaches have rapidly eroded, alarming sea turtle conservationists.
While loggerheads have been protected as a threatened species for decades, their numbers continue to
decline, in large part due to fishing gear that kills turtles incidentally as bycatch. In August the National Marine
Fisheries Service (NMFS) issued a new status review showing that loggerhead sea turtles off the U.S. Atlantic coast are currently at risk of extinction.
We were wired to see a nesting, but the first night passed without any sea turtle sightings, and the second night went by uneventfully, too. We were on call: If the BHIC interns found a turtle, they would call my cell phone
immediately, no matter what time of night.
On the third night around 11 p.m. we saw a red headlamp flickering 100 yards or so down the beach. As the light got closer, we heard an intern shout, “Turtle!” and we dashed down the beach.
We slowed when we spotted a dark oval on the side of the dune. Incredibly, this female sea turtle was climbing a steep dune in her search for suitably dry nesting sand – the ideal spot for a nest is flat and smooth. I could see that she was dexterously moving sand aside with her back flippers.
“She’s digging her egg chamber,” said BHIC sea turtle biologist Brett DeGregorio. We watched, stunned, as this massive reptile carefully attempted to dig a hole for her eggs on the steep incline.
Within minutes, she gave up. When she took off toward the water, the interns barely had enough time to scan her for ID, a Passive Integrated Transponder (PIT) tag before she was back in the ocean.
The BHIC is one of a handful of programs in the Southeast United States that holds all-night beach patrols from mid-May to mid-August, and has collected sea turtle data since 1980. As one of the farthest north nesting beaches, Bald Head Island is also critical in supplying male loggerheads to the population. Sea turtle gender is determined by the temperature at which the eggs incubate: cooler sand means more males, warmer means more females. As a result, Florida tends to have more female hatchlings while North Carolina has more males.
When my phone buzzed at 2 a.m. the last night, we dashed, bleary-eyed, to the beach. This was our final chance to see a sea turtle nesting.
When we arrived, the turtle was at work digging her egg chamber, so we stayed at a distance. As soon as she started dropping eggs into the chamber, we moved closer. She was in the trance that female sea turtles enter during the egg laying process, allowing the interns to measure her shell and check her for tag IDs.
As soon as she was back in the water, two interns got to work uncovering the eggs to relocate them away from the high tide line. They were meticulous, and it was clear they were trying their hardest to give these eggs a chance for survival. The odds of a sea turtle hatchling making it to maturity are less than one in 1000 by some
Watching the dedicated BHIC interns, it occurred to me that sea turtles need advocates in and out of the water. While the Conservancy works tirelessly to protect hatchlings and nesting mothers, they can’t do much about the risk of getting caught in fishing gear such as trawls and longlines, which is where Oceana’s campaign to protect sea turtles comes in.