As you may know, the Island Turtle Team has collected genetics samples from every loggerhead nest laid on the Isle of Palms and Sullivan’s Island for 13 years as part of a multi state research project along the Atlantic Coast. This sample is found where the mother turtle leaves a few cells in the inner lining of an eggshell.
Dr. Brian Michael Shamblin at the Warnell School of Forestry at the University of Georgia started this innovative method of monitoring the Atlantic Coast loggerhead population over a decade ago. This portion of the coast, north of Florida, is known as the Northern Recovery Unit. This population of turtles is genetically different from Florida’s loggerheads.
Some of us remember first meeting Brian at the International Sea Turtle Symposium, when he was a predoctoral graduate student presenting this idea to sea turtle experts from all over the world. The paper he presented introduced a huge innovation using genetics testing never before utilized in sea turtle research.
Most recently, Brian let us know about an interesting discovery relating to one of our Isle of Palms nesting moms known in the project as CC002992. Since 2011, she has been recorded as laying 30 nests on the Isle of Palms, almost always at the northern end at Ocean Point and in Dewees Inlet. We have documented the location, number of eggs and hatchling success for all of her nests over the years.
Regarding this female turtle, according to Brian, “She has six daughters that have started nesting since 2018. … All six are nesting nearby but one as far away as Ocean Isle, North Carolina. … What’s even more incredible is that all six are full sisters – they share the same dad. Given the size of the population, we think it is unlikely that the same pair of loggerheads would mate across breeding seasons, so we suspect that all six of these turtles hatched the same year. … It is extremely difficult to measure survival in juvenile sea turtles, but we suspect that most hatchlings that make it into the water likely perish before their first birthday. … It may take a female’s entire lifetime to produce a daughter to replace herself in the population.”
He developed a graphic showing locations where three of the six daughters have nested since 2018. He said he ran out of space for more, but those three now nest regularly – one on Dewees Island, one on Capers Island and one on Pawleys Island.
We are constantly amazed and impressed with his project and Brian’s work. We now have nests hatching and being inventoried to gather data. We are able to tell our volunteers who found and protected each nest exactly who the mother of those hatchlings is, as well as where and how many times she has nested.
But the sad news is that after over a decade, the federal grant money for this ongoing research has been stopped. We are hoping it can be continued, and that is why some South Carolina nesting projects, including ours, are raising money and donating to this very valuable and ongoing research project.