UPDATED 15 AUGUST: Kemp's Ridley Nests at Outer Banks
by Jackie Orsulak
: Rare Kemp's Nest on OBX
The sea turtle nesting season of 2012 has begun on the Outer Banks of North Carolina, and awesome things are happening! So far we have six loggerhead nests, as well as Nest #5, a Kemp’s ridley nest we are calling “Kaylie’s Nest.”
For those of you new to Outer Banks sea turtle nesting, the Kemp’s ridley (Lepidochelys kempii) is the smallest and rarest of the world’s sea turtles. They primarily nest on an 18.6-mile stretch of sand that runs across Rancho Nuevo, Mexico; there is also a small population established on South Padre Island, Texas, and they are occasionally found elsewhere, including the beaches of North Carolina.
There once were many Kemp’s ridleys. These turtles would come ashore in what is known as an arribadas (mass nesting). Over a period of a few days, hundreds of turtles would come to nest on the beaches of Rancho Nuevo. There is a video of 40,000 turtles coming ashore to lay their eggs in one day in 1947; if you want to see it, please ask permission from a parent or teacher and then watch it here on YouTube.
Some people in that area consider turtle eggs to be an aphrodisiac. This makes the eggs very valuable, so some local people collect as many eggs as they can to sell. With the over-harvesting of the eggs and with net fishing, the Kemp’s ridley species almost became extinct. They are coming back slowly, but still are considered critically endangered. With the help of conservationists throughout the world—and of the Endangered Species Act of 1973—there is now hope this species will survive.
In the United States, a person can receive a $100,000 fine and/or a year in jail for harassing, collecting or harming sea turtle eggs, hatchlings or adults in any way. In Mexico, environmentalists have worked to protect both the animals and the culture of the local people. The people are allowed to collect the eggs on the first day of the arribadas. These eggs would probably be damaged anyway by the many turtles that come in the succeeding days to nest. While digging their nests, they would probably dig up many of the eggs laid the night before. This solution benefits both the people and the animals.
For the third year in a row, one of these very endangered turtles has nested on the beaches of the Outer Banks. What is even more exciting is that the Kemp’s ridleys frequently come ashore to nest in the daylight, most often when the winds are strong. That was the case on the day “Kaylie” nested. A wonderful tourist, Susan Ellett from Richmond, Virginia, saw her come ashore and knew to call the Network for Endangered Sea Turtles (NEST) hotline. As a 12-year NEST volunteer, it was an incredible experience for me to see a nesting sea turtle in daylight—and this a great opportunity to share the event with turtle fans on FieldTripEarth.
Kaylie came out of the sea to an area of the beach prone to erosion. Homeowners recently had arranged for tons of sand to be dumped on the beach to build up the dunes and to protect their homes and the beach. The turtle climbed to the top of the pile of sand but was not pleased with it. It was probably very loose and not as compacted as she would find on a regular beach. She then slid down the dune and crawled to another spot at the toe (bottom) of the dune and began digging her nest cavity at about 8:45 in the morning.
[Of course, if you see a sea turtle on the beach during nesting season, it is very important to stay away and to remain very quiet while she digs her nest. She cannot see as well on land as she can in the water. Being on land is a very scary environment for her. If she sees any movement or hears any noise, she may head back to the water, leaving us with a “false crawl” and no nest.]
Since she is much smaller than the loggerheads that usually nest on our beaches, her nest was not deep. Once she dug her nest, she began to deposit the eggs in the nest chamber. During this time, she seemed to be in a trance. We carefully approached her from the rear and took pictures of this amazing event. She looked like she was crying, though the sandy, salty tears were actually secretions of saltwater from glands in her eyes. This is a sea turtle’s way of ridding her body of saltwater.
She seemed to catch the eggs with a rear flipper and then lowered each into the hole. When she finished laying the eggs, she covered them with sand. Unlike the loggerhead or (in particular) the green turtle, she did not throw mounds of sand over the eggs with her front flippers. Instead, she just used her back flippers to pull sand over the eggs and pat the sand down. When she finished covering the eggs, she slowly turned and crawled back to the ocean.
In a sense, she left the eggs for us to protect. We hope she will come back and lay another clutch in 10-28 days. These turtles mature at about 10-12 years of age and can live to be 50 years old. If we see her again we will know it is the same turtle, as she has very unusual notches on the rear outside (marginal scutes) of her carapace (shell). This could be what is called a “living tag.” When she was a hatchling, her shell may have been notched for future identification. We are trying to find out if this is why her shell is so unusual. We will let you know what we find out.
Researchers at the University of Georgia are doing a study on female loggerheads. We take an egg from each nest for DNA sampling. Two years ago, before a nesting turtle was identified as a Kemp’s, researchers took an egg for the study. It was decided to take one egg from this nest to compare with the other Kemp’s DNA, even though this study is focused specifically on loggerheads.
Emily Veigel from Indianapolis, Indiana named the turtle “Kaylie.” You can see Emily helping Karen Clark, the wildlife educational specialist for the Outer Banks Center for Wildlife Education, collect the tissue from the shell of the egg for DNA sampling.
Even though these turtles are less than half the size of loggerheads, the eggs are still about the same size—about that of a ping pong ball. Do you think the hatchlings will be the same size as the loggerhead hatchlings? How many eggs do you think she put in the nest? Do you think since the mother nested in the daylight maybe the hatchlings will emerge in the daylight? Since the Kemp’s nest is much shallower than the larger turtles it may incubate faster. We will wait 45 days and begin sitting out on the beach watching for the little hatchlings to emerge to find the answer to those questions. We’ll report back to FieldTripEarth as we learn more.
: Kemp's Nest Update - 5 August 2012
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