99% of These Sea Turtles Are Turning Female—Here’s WhyAt the Pacific Ocean's largest green sea turtle rookery, a crisis is unfolding, likely thanks to warming temperatures. Will this become a global problem? RISING TEMPERATURES CAUSE SEA TURTLES TO TURN FEMALE
By Craig Welch
PUBLISHED JANUARY 8, 2018
https://news.nationalgeographic.com/2018/01/australia-green-sea-turtles-turning-female-climate-change-raine-island-sex-temperature/[...]
Pacific green sea turtles spend years cruising this northern Australia feeding ground, fattening up on sea grasses before heading to nesting areas to mate and lay eggs. The scientists simply wanted to know: which of these reptiles were male and which were female?
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Since the sex of a sea turtle is determined by the heat of sand incubating their eggs, scientists had suspected they might see slightly more females. Climate change, after all, has driven air and sea temperatures higher, which, in these creatures, favors female offspring. But instead, they found female sea turtles from the Pacific Ocean's largest and most important green sea turtle rookery now outnumber males by at least 116 to 1.
"This is extreme—like capital letters extreme, exclamation point extreme," says turtle scientist Camryn Allen, with the National Oceanic and Atmospheric Administration in Hawaii. "We're talking a handful of males to hundreds and hundreds of females. We were shocked."
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