Global warming threatens 'feminization' of green sea turtles

The Drastic change in temperature increased the female nesting ratio, likely to reach 93 percent by 2100.

Madrid: Global warming is threatening 'feminization' of green sea turtle, a study has said suggesting that by 2100 up to 93 percent of the hatchlings of this species could be females. The sex of turtle hatchlings is determined by temperature and currently, approximately 52 percent of green sea turtles (one of the seven species of marine turtles) are females, according to a study published in the Global Change Biology journal on Wednesday.

The study by the British University of Exeter and the Portuguese Marine and Environmental Sciences Centre indicated that with the scenario of warmer temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), between 76 and 93 percent of the offspring of those sea turtles would be females. The data refers specifically to the Bijagos archipelago in Guinea-Bissau in Africa, one of the most important nesting area.

However, researchers expect "a similar picture globally", according to a statement from the University of Exeter. The change in the proportion of gender would initially lead to a larger number of females nesting, increasing the population, before a decrease "as incubation temperatures approach lethal levels". In addition, on the beaches where the study was conducted, experts predict that rising sea levels will submerge from 33 to 43 percent of the areas where the green turtles nest.

One of the authors of the study, Rita Patricio, of the University of Exeter, warned that the green turtles "will have to face problems in the future due to the loss of habitat and increase in temperatures". However, cooler temperatures, both at the end of the nesting season and in some shaded areas, will ensure that some hatchlings are male, she added.