Climate change turned 99 percent turtles into female
New Delhi : 99 per cent turtles living in the crystalline waters of the northern Great Barrier Reef are female green sea turtles. Scientists suspect that it is a result of climate change our planet is going through.
In one of the world’s largest sea turtle colonies, home to some 200,000 endangered animals, there are almost no young males. More than 99 percent of the turtles born on the reef’s northern beaches since the late 1990s have been female – the alarming outcome of rising global temperatures, according to a groundbreaking study published Monday, January 8, in the journal Current Biology.
The gender of a turtle heavily depends on the temperature during the incubation period in the eggs. The cooler surroundings make it easy for turtles to turn out into males while warmer conditions are responsible for female births.
Such temperature-dependent sex determination occurs in many reptile species and can benefit a population with more breeding females. Too many females and too few males, however, could spell disaster.
Since a massive population of green sea turtle never bothered anyone to look at this aspect, the temperature dependent sex change has now evolved as a major threat for the species.
The authors of the new study – led by Camryn Allen and Michael Jensen, both researchers with the United States National Oceanic and Atmospheric Administration (NOAA) – warn that rising global temperatures could cause the “feminization” of most sea turtle populations, rendering them unable to reproduce and possibly threatening this population with extinction.
“We also know that higher incubation temperatures cause higher mortality in the eggs,” Allen said in an interview.
“it is clear that climate change poses a serious threat to the persistence of these populations,” the study concluded.