Why are sea turtles turning female?

The sex of sea turtles is not determined purely genetically, as it is in humans. The temperature during the development of the embryo will determine whether a male or a female turtle hatches. Higher temperatures result in females, lower in males.

Increasing sand temperatures on nesting beaches can therefore shift the sex ratio of hatchlings to almost entirely female. As a result, turtles may have a problem reproducing in the future.

Nesting female olive ridley turtles, Aribada. Image.
Nesting female olive ridley turtles.
Olive ridley turtle hatchling leaving the nest. Image
Olive ridley turtle hatchling leaving the nest.


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