Sexing sea turtles

Researchers at Florida Atlantic University have developed a new way to determine the sex of endangered baby sea turtles, publishing their findings in the journal The Anatomical Record.

While many species use sex chromosomes - such as our own mammalian X and Y chromosomes - sea turtles do it differently.

Eggs that are incubated in warmer temperatures tend to produce females, while those laid on cooler sand are more likely to be males.

The new test focuses on measuring the levels of a protein called CIRPB, which is found in high amounts in the developing ovaries of female turtles, even at the hatchling stage, but at much lower levels in males.

When researchers compared CIRPB measurements to conventional turtle-sexing techniques, the new test had a 93 per cent success rate for loggerhead turtles and 100 per cent for leatherbacks, suggesting the test is reliable and reproducible.

As global temperatures rise, there’s evidence that this is skewing sea turtle populations in a more female direction, which could risk sending the species towards extinction if there aren’t enough males to go round.

To make things more tricky, a sea turtle’s sex isn’t obvious from its anatomy until it starts to approach sexual maturity, which can take at least a decade.

Developing this method to quickly and easily determine the sex ratios of newly hatched baby sea turtles is a vital tool for conservationists trying to track and preserve the species.