More than 1,100 dead olive ridley sea turtles have washed ashore on the beaches of Tamil Nadu state in southern India this January.
“I never heard [of] such large numbers of turtles stranded at any beaches of Tamil Nadu at least in the last three decades,” Kuppusamy Sivakumar, an ecology professor at Pondicherry University said.
Most of the washed up turtles were found near the state capital, Chennai. Every year, olive ridley turtles (Lepidochelys olivacea) gather off India’s coast to breed. Female turtles come ashore to the beaches where they hatched to lay their own eggs, while the males remain in the water. Typically, between 100 and 150 turtles nest on Chennai’s beaches annually, so the stranding of more than 1,000 turtles is surprising, Sivakumar said.
Chennai resident Rajiv Rai said he had spotted about 80 dead turtles on a 2km (1.24 mile) stretch of beach near his home. He said he alerted the state’s forest department, whose staff bury the carcasses, although the burials are now lagging.
An initial necropsy of one carcass revealed lung lesions; many dead turtles had bulging eyes. Both observations indicate the turtles are likely to have died from suffocation and drowning, Yuvan Aves, a Chennai-based environmental activist said. The official postmortem report has not yet been made public.
Aves said he had also observed an unusually large number of male carcasses on the beach.
The reasons for the mass deaths are unclear. However, Sivakumar said both male and female turtles could have gathered near nesting beaches to breed. If there was net fishing in the area, the turtles, which need to surface to breathe, may have become entangled and drowned.
If that were the case, Sivakumar said, it was difficult to say whether the turtles got caught in fishing nets near Chennai or further away, then ended up off Chennai due to winds or currents.
Aves said commercial fishing vessels operating in Chennai’s waters often do not abide by local laws, which was likely to have contributed to deaths. Tamil Nadu, for example, has banned trawlers within five nautical miles (9km) from shore, but the law is not typically enforced. Trawler nets must also have turtle excluder devices installed, but “notoriously, nobody has it,” Aves said.
After media coverage of the crisis, the Tamil Nadu government caught 24 trawler boats operating illegally in Chennai’s waters, and has created a special taskforce in response. The government said in a release that a joint patrol team is now monitoring boats and ships in the area.
Manish Meena, Chennai’s wildlife warden, said that “night patrols have been intensified to protect hatchlings”.
The scale of death of a species that was once endangered and has only partly recovered due to conservation efforts “exceeds one’s capacity of feeling,” Aves said. “You can stand on the coast right now anywhere in Chennai and every few strides, you can see bulge-eyed turtles till the horizon.”
This story was originally published by Mongabay
