Olive ridley turtle nest numbers along city’s coastline up, experts surprised

Chennai: A rise in the number of olive ridley sea turtle nests along the city's coastline this season has given conservationists an unexpected boost this season. The number of nests documented was 206, a notable increase from the 162 recorded during the same period last year.
State forest secretary Supriya Sahu noted that the season began with concern, as the lowest nest counts in 25 years were recorded in Jan and there was a surge in the number of dead turtles washing ashore.
However, the recent uptick in the number of turtle nests has brought relief to conservation efforts. So far, Chennai wildlife authorities have collected 26,994 eggs, with 706 hatchlings already released into the wild. The olive ridley turtles, which primarily nest along the East Coast, are also known to migrate toward the West Coast.
R Suresh Kumar, a senior scientist from the Dehradun-based Wildlife Institute of India (WII), said that the East Coast remains a high-density nesting ground. While turtles sleep underwater for long durations, they must surface periodically for air while swimming or foraging.
On the issue of increasing turtle mortality along Tamil Nadu's coast, Suresh Kumar pointed out that a decade-long study would be needed to assess the role of climate change in this. For now, he attributes the deaths mainly to fisheries-related activities.
P Padmanabhan, a scientist from the Zoological Survey of India, Chennai, recalled that a 2017-18 survey had recorded fewer dead turtles washing ashore. He noted that while the current Chennai coastline has core sand, ideal for nesting, it has also seen a rise in turtle deaths.
The nesting journey for female turtles is gruelling. After mating, they forage and travel up to 2,000 km along the coast before nesting. Weakened by the long journey, they become vulnerable to getting trapped in trawling nets. Many die from strangulation, their bodies often found with bulging eyes a clear sign of asphyxiation.