Climate Change Is Churning Out More Female Green Sea Turtles

Researchers found that a population of green sea turtles residing in the northern Great Barrier Reef is almost made up entirely by females.

A large population of green sea turtles mostly consists of females thanks to climate change.

Rising ocean temperatures are altering marine life, a feat that will worsen with each passing day. Scientists have focused on a particular population of green sea turtles and discovered that almost all of them are female. According to study dealing with the phenomenon, this sudden shift is directly linked to climate change.

99 percent of green sea turtles currently inhabiting the northern part of Australias’s Great Barrier Reef was found to be almost exclusively female. Researchers warn that this imbalance poses a serious threat to the survival of the already endangered species.

Turtles are very different to humans when it comes to choosing one’s sex, as these animals develop into males and females depending on the temperature outside of their egg, The smallest temperature difference can decide the sex of the turtle. For an even split between males and female turtles, the temperature has to be 29.3 degrees Celsius.

“Within a few degrees Celsius you go from 100 percent males to 100 percent females,” said marine biologist, Michael Jensen.

Researchers looked at green sea turtles which originated from two unique breeding grounds. One population was from the warmer northern Great Barrier Reef while the other population was from a cooler area situated at about 1,200 miles to the south.

The results were worrying to say the least, as the population that hatched in cooler areas was about 69 percent female while the population in the warmer north consisted of 99 percent juvenile and young adult female turtles.

Study co-author, Camryn Allen, and his team were able to compare ratios across turtles of different ages, which soon led them to realize that older turtles from the north had a less extreme ratio. According to Allen, there has been a drastic change in the turtle sex ratio in the past twenty years. Now, it seems that there is one male turtle for one hundred females.

Researchers noted that the problem seems to be getting worse with each generation. If ocean temperatures do not stabilize or decrease in temperature, they warn of a “complete feminization” of this population of turtles.

The study was published in the journal, Current Biology.

Image Source: Seeturtles

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Roxanne Briean

I am a geek, a gamer and a writer. I have always been fascinated with the online community. At the moment I work as a full-time writer and study interior design. When I'm not scouring the net in search of interesting new gadgets and software I spend my time in MOBAs or drawing.