Humans may have skewed up their sex ratios due to cultural reasons, but their careless actions on land is affecting sex ratios of turtles in the sea. The warming ocean water, contributed by climate change is leading to more female turtles being born in the wild. Green see turtles, nesting in Raine Island off Australia's east coast are showing this alarming trend.
A news report published in journal, Current Biology said scientists found 99 percent of baby turtles born in the island to be females while the population currently has 87% adult females. For every juvenile male, there are 116 female turtles. Unlike human beings, sex in green sea turtles is dependent on environmental conditions. Warmer waters convert an egg to female while the temperature of 29.3 degree celsius results in males. The change in sex is affected by a very small temperature change.
"They have temperature-dependent sex determination," reported, NDTV, quoting Camyrn Allen, a National Oceanic and Atmospheric Administration endocrinology researcher and co-author of the new study. "It's not genetics. It's actually the temperature."
Scientist are blaming the changed sex ratio to warmer sand where the turtles lay their eggs. Another nesting area South of Raine island has beaches with relatively cooler temperatures and there the sex ratio seems to be close to normal with 1 male turtle to 2 female turtles.
But the population may not be doomed just yet, as manual intervention can still save the turtles through acts like shading the beaches or pouring water on the sand to cool the nesting areas.