Will they get stymied by a tire track in the sand? Some turtle hatchlings get confused by artificial lights and crawl away from the water, heading to parking lots where they die. Or maybe a crab, raccoon or some other predator will nab them before they get to the water. That’s why South Carolina’s Cape Romain National Wildlife Refuge, which has the largest nesting population of loggerhead sea turtles outside of Florida, has worked diligently for decades to increase the number of hatchlings entering the surf. The sea turtle recovery program has been successful because partners and scores of volunteers have made it a priority to get those baby turtles in the water for more than 30 years.
An eight-person crew, working seven days a week from April through September, uses three boats and four ATVs to survey the nesting areas, relocating nests that are laid in areas of overwash or in areas subject to the erosion, and protecting the hatchlings from predators by an active trapping program and wire exclosures over each nest.
More than 5,000 hours are invested annually in this program with considerable help from the refuge’s partners, including the South Carolina Department of Natural Resources, South Carolina Aquarium, Dewees Island Conservancy, the Service’s Charleston Ecological Services Office, the Sewee Association and more than 40 volunteers every year. These cooperative partnerships at Cape Romain have a greater impact on fish and wildlife than any partner could hope to have acting alone.
Because Cape Romain has only one biologist to survey for and protect nests on 15 miles of beach on four separate islands, each of which are accessible only by boat, what has been accomplished all these years is incredible. The turtles that were rescued 30 years ago are coming back to lay their own nests. And that is probably why the 2013 nesting season has produced twice as many nests as the yearly average for the refuge. As of September 11, loggerheads had built 1,912 nests at Cape Romain. That’s 200 more than last year and the highest count since 1978, when the species won national protection.
This is the third year in a row the refuge has seen the total nest count increase from the previous year.
The Cape Romain sea turtle recovery program’s nest relocation and predator protection efforts increase the chances that eggs in those nests will hatch. Hatch rates rose from 23 percent without recovery efforts to 80 percent. In 2012, 142,408 hatchlings were produced on refuge beaches. In about 30 years, the benefits of that bumper crop of turtles will be seen because loggerhead sea turtles reach sexual maturity after about 30 years and return to nest on where beaches they were born.
But climate change is threatening sea turtles with a double whammy.
With a changing climate feeding sea level rise, sea turtles might not even have a beach anymore as a nesting spot. Beaches are eroding away or just disappearing under the water. Even if the nesting areas start off dry, nests are in danger of being flooded. At Cape Romain, more than 70 percent of all nests must be relocated, due to sea level rise that accelerates the erosion of sandy beaches where turtles nest. The sea has risen more than 1 foot in 100 years at the refuge, near Charleston, South Carolina, according to NOAA, and it is expected to continue rising at even faster rates in the future.
A clear sign of the rising water at Cape Romain is the “no dogs” sign. It’s surrounded by water.
The refuge has lost 2,100 acres so far on refuge beaches. Although nesting beaches are rapidly shrinking, the number of nests laid on the on refuge beaches has nearly doubled. It is uncertain where the turtles will go when the islands disappear completely.
Part of the answer may lie in the results of genetics research that has been carried out by the sea turtle coordinators from Georgia, South Carolina, North Carolina and the University of Georgia. With the help of sea turtle protection groups in each state, one egg from each nest has been collected for the last four years. DNA studies on the egg shell yield a genetic blueprint for each nesting turtle. The extraordinary amount of information that just one egg can provide has never been revealed until now. Because sea turtles return to the area where they hatched decades earlier, the results of the genetic study will reveal where sea turtles nest today, and in time the study will reveal how they adapt to the effects of climate change over time.
An ominous sign of past events at Cape Romain.
This post once marked an island fully above water.
The sign uselessly warns, “No pets allowed.” .
But it’s not just beach loss – egg temperature helps determine the gender of some hatchlings as well (those of the green sea turtle, for instance). Warmer temperatures generally result in more females, which may sound good if you are a single male sea turtle on the prowl. But it is NOT good for the sustainability of a species. So, sea turtle nesting numbers are hitting records this year all along the southeast, but the future of the species is really unknown in the face of the changing climate.
The South Atlantic Landscape Conservation Cooperative is trying to bring some certainty to the equation by funding a study that looks at the effects of sea level rise on sea turtle, shorebird, seabird and beach mouse nesting distributions.
Researchers will look at past nesting patterns and predict future effects of sea level rise on nesting beaches. They will also estimate the cost to humans associated with losses of sea turtles and the other species, including losses in ecosystem services, tourist attractions, housing, land and jobs. Researchers will also estimate the benefits of responding to sea level rise, with measures including beach restoration or limiting development within a certain distance of coastlines. Finally, they will try to find the best response strategies by estimating and comparing their costs — cost of stopping development in an area — and benefits– sustaining ecosystem services. An online tool will allow users to change the values of ecosystem services and come up with their own cost and benefit estimations.
The study currently leaves out South Carolina, and staff at Cape Romain are eager for the study to be expanded to their state. The research will help decision makers choose how best to help the species and the human population and expand the scientific foundation for future management decisions.
We can’t stop a changing climate, but we can do our best to help species adapt to warmer weather. The study will make life easier for sea turtles and by helping their decision-making, it will help refuge managers, too.
This article was contributed by Matt Trott, Communications Office, U.S. Fish and Wildlife Service
To learn more about Cape Romain, or the management challenges associated with a changing climate, check out Cape Romain’s Climate Profile.