By Aurora Zhang, Guest Contributor
Global warming has many severe effects on our blue planet including coral bleaching, native species dying, and invasive species thriving. One effect, however, remains hidden despite its great potential for harm—the rise of an unstable sex ratio within the sea turtle population.
When female adults lay eggs, the sex of the turtles is not predetermined; instead, the temperature of incubation determines the sex of the turtles which hatch from the eggs.
The female sex tends to favor higher temperatures during the incubation period. Due to global warming, there are increasing numbers of female turtles. Climate change causes over 99 percent of the Green turtles incubated in the Great Barrier Reef to become females. To beaches north of the Great Barrier Reef, scientists have found that almost all juveniles are female and over 85 percent of the adult population is female. South of Great Barrier Reef, even in cooler regions, the Green turtle population encounters the same crisis—approximately 70 percent of the hatchlings (baby turtles) are female.
“Finding that there are next to no males among young northern green turtles should ring alarm bells,” Dermot O’Gorman, the chief executive officer of the World Wide Fund for Nature (WWF) Australia, said. This unbalanced sex ratio the world encounters will cause the turtle population to dramatically decrease even more when paired with deaths caused by ocean pollution.