Sea Turtle Hatching in Costa Rica

Seeing baby turtles (AKA hatchlings) is one of the best things about visiting a sea turtle nesting beach, and being able to help a sea turtle hatchling by protecting its nest is one of the most rewarding parts of our job.

Approximately 60 days after a female sea turtle lays her eggs, the hatchlings break the eggshells with a specialized egg tooth and, helped by its siblings, emerge to the surface of the sand. Because they are easy target to predators once they have emerged from the nests, hatchling sea turtles make a break towards the sea. After entering the water, hatchlings will swim tens of miles using up the energy that was contained in the egg yolk until they find suitable oceanic currents and protective environments, such as floating algae. In theory, hatchling sea turtles will spend their first years associated with this environment that can provide them with food, protection from predators, and a thermal advantage essential for the development of these cold-blooded (ectothermic) reptiles. However, so little is known about the fate of hatchling sea turtles after they enter the sea that this phase of their lives is commonly referred to as “the lost years”. Turtle Love’s Scientific Director, Renato Bruno, is currently researching the biology and ecology of lost year sea turtles off the Caribbean coast of Costa Rica, check out this blog post.

An interesting fact about sea turtle hatchlings is that the sex of the hatchling is only determined by the middle of the incubation period – 20 to 30 days after the turtle laid the eggs. Once the embryo development starts, the temperature during this period influences the sex of the hatchlings being produced. This is called temperature-dependent sex determination, and in sea turtles warmer temperatures produce more females, while cooler temperatures produce more males. An easy way to remember this: hot chicks and cool dudes!!!