The Tamil Nadu Forest Department has set up ‘climate-resilient’ hatcheries for Olive Ridley sea turtles, which arrive at the coast to nest from January to April, to ensure better survival of the turtle hatchlings.
As many as 10 hatcheries — two each in Chennai and Nagapattinam, one each in Villupuram, Cuddalore, Nagapattinam, Tirunelveli, Ramnad, Thoothukudi and Kanniyakumari — have been established at a total cost of ₹10 lakh. A government order issued in this regard on December 29, 2023 says that such hatcheries ensure optimal incubation conditions for eggs, and produce healthy and resilient hatchlings.
Conservation efforts ramped up
“With cognisance of the effects of climate change on Olive Ridleys, we reached out to the Wildlife Institute of India (WIII) to strengthen our conservation efforts,” said Supriya Sahu, Additional Chief Secretary to Departments of Environment, Climate Change and Forests, explaining that there are two things that set these upgraded hatcheries from the normal ones.
One, the hatcheries have been equipped to constantly monitor temperature through data loggers, which capture the weather conditions and display it in the form of a graph. This will be monitored by the District Forest Officers and other forest staff overseeing the hatchery.
The other aspect of the hatcheries is that they are designed to be adaptable by adding a layer of roofing in the afternoons when the weather gets warmer. “These are some fundamental steps being taken now,” said Ms. Sahu. While hatcheries are usually temporarily set up during the annual nesting season, there could be a need for establishing semi-permanent ones, she added.
Baseline data on hatching pattern
According to R. Suresh Kumar, a scientist with the WII currently studying sea turtle populations arriving along the Indian coast and turtle hatchery management practices, the temperature inside pits, where eggs are placed, could be different from the ambient hatchery temperature.
Warmer temperatures are known to produce a higher proportion of female hatchlings and cooler temperatures lead to a higher proportion of males from the nests. “Sea turtles exhibit temperature-dependent sex determination with pivotal temperatures close to 30°C,” said Mr. Kumar.
Further, the hatcheries could unintentionally skew the gender ratio as they are set up far from the high tide line, making it warmer than ideal sites chosen by the turtles. “There is no straightforward solution. At this point what we’re doing [with data loggers] is documenting the present conditions and outcomes. This will be the baseline data for further measures to be taken,” he said.
