Blog Post By: Sarah Glover, Sea Turtle Intern
Once they hatch from their eggs, loggerhead sea turtles only have a 1 in 1000 chance of surviving to adulthood (30 years of age). These tough odds are why they have evolved to lay about 120 eggs per nest and 3-5 nests per season. As soon as the eggs are laid, the turtles face countless natural and human threats.
First of all, these turtles face several predators. On our beach, eggs are often predated by raccoons and ghost crabs. Coyotes also commonly dig into nests on other beaches such as Botany Bay. Laughing gulls are quick to scoop up hatchlings, especially when there is a crowd of people watching them make their crawl to the water (so don’t feed the birds – it makes them associate humans with food!). As adults, loggerhead sea turtles are hunted by tiger sharks. In some regions, sea turtles are even hunted by humans for their meat and shells, and eggs are taken by poachers.
Storms, natural coastal erosion, and rising temperatures also pose threats to loggerhead sea turtles. Storms may lead to nests being washed over. Nests can experience a few washovers. In fact, it is good for them to experience a few as this cools down the nest. However, too many washovers and the eggs can drown. Coastal erosion causes there to be less nesting grounds for the turtles. Rising temperatures can skew the male to female ratio in a nest. The sex of sea turtles is dependent on temperature (hot chicks, cool dudes), so if the nest gets too hot, then it will produce mainly females. Additionally, if the temperature gets too hot, then the whole nest may become unsuccessful.
The loggerhead sea turtles also face several human threats. Lights (both from houses and on the beach) can cause adults and hatchlings to become misorientated and disorientated. Misorientation is when the turtles move in the opposite direction of the ocean due to a brighter light source. Disorientation is when turtles move randomly before eventually finding their way to the ocean (making loops and turns). Plastic pollution also has a major impact on sea turtles. Plastic bags, for example, may look like a jellyfish floating in the water, which is a major food source for sea turtles.
In South Carolina, the number one cause of stranding is boat propellers. Since sea turtles have lungs, they need to come to the surface to breathe and often get struck by the propellers of passing boats. Fishing practices, such as ghost nets, hooks, and shrimp trollers, can harm sea turtles as well through entanglement and ingestion. However, thanks to the Turtle Excluder Device (TED), sea turtles are less at risk of being trapped in the nets of US shrimp trollers.
So remember, don’t use white lights on the beach from May-October, buy local sea food (to ensure a TED was used), and pick up your trash to help save the turtles!
Sea Turtle Biologist