Thu Apr 10 03:57:36 UTC 2025: ## Climate Change Skews Olive Ridley Turtle Sex Ratio in Odisha

**Bhubaneswar, Odisha –** A 15-year study has revealed a concerning trend in the Olive Ridley sea turtle population at Odisha’s Rushikulya River mouth. Rising temperatures are causing a skewed sex ratio, with a significantly higher number of female hatchlings being born.

The research, titled “Monitoring sea turtles in India 2008-2024,” conducted by Dakshin Foundation, the Centre for Ecological Sciences (IISc Bangalore), and the Odisha State Forest Department, analyzed data from mass nesting events. These arribadas, unique synchronized nesting events, are crucial for the survival of this endangered species. Rushikulya is one of two major arribada nesting sites in Odisha, and the East coast of India is home to a genetically distinct population considered ancestral to Olive Ridleys worldwide.

The study found an average of 71% female hatchlings, with some years showing extremely female-biased ratios due to high nest temperatures. While a few years displayed male-biased ratios, the overall trend indicates a feminization of the population due to climate change. Researchers used gonad histology to determine hatchling sex and established a pivotal temperature for sex determination in this population.

Although the overall Rushikulya population appears stable or even increasing, with between one and two lakh turtles nesting annually since 2008, the researchers warn about the long-term implications of this skewed sex ratio. The potential for a severely imbalanced population, impacting future breeding, is a serious concern.

Kartik Shanker, a leading researcher on Olive Ridley turtles, emphasized the importance of long-term monitoring for understanding population trends and predicting the impact of climate change. This data is vital for guiding conservation strategies and involving local communities in long-term turtle conservation efforts. Further research, incorporating additional temperature data and embryo growth models, is planned to better understand the long-term trends.

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