Bhubaneswar: In an extraordinary event that has surprised marine biologists and conservationists, an Olive Ridley sea turtle tagged on Odisha’s Gahirmatha beach has completed an unprecedented 3,500-kilometre journey to Maharashtra’s Ratnagiri coast. The journey defies an established understanding of the species’ migratory behaviour and opens new frontiers in sea turtle research.
Tagged with number 03233, the turtle was among nearly 12,000 Olive Ridleys flipper-tagged by the Zoological Survey of India (ZSI) during the mass nesting season at Gahirmatha in 2021. After nesting on Odisha’s east coast, the turtles were expected to head southward towards Sri Lanka, following their typical migratory route. But turtle 03233 took a completely different path.
Instead of migrating south, it swam westward across the Indian peninsula and reached Guhagar beach in Maharashtra’s Ratnagiri district. There, it laid another clutch of 120 eggs, with 107 hatchlings successfully emerging—marking the first recorded instance of an Olive Ridley nesting on both the eastern and western coasts of India.
Dr Basudeb Tripathi, senior scientist at ZSI, called the discovery “exceptionally significant,” noting that it challenges the long-held belief that Olive Ridleys nesting on India’s east and west coasts belong to genetically distinct populations with separate migratory routes. “This journey points to a possible genetic or behavioural connection between the two populations,” he said.
Researchers have nicknamed the turtle ‘Marco Polo’ for its trailblazing journey. Dr Suresh Kumar, a sea turtle specialist at the Wildlife Institute of India (WII), suggests that the turtle may be exhibiting a dual reproductive strategy—laying clutches at different locations to boost offspring survival amid changing environmental conditions.
“This behaviour may reflect an adaptive response to climate change, habitat degradation, and predation pressures,” Dr Kumar said. “By spreading their eggs across regions, the turtles might be ensuring that at least some offspring survive.”
The discovery has sparked calls for stronger protection of nesting beaches all along India’s coastline. Conservationists stress the need to safeguard not only established sites like Gahirmatha and Rushikulya in Odisha but also less-recognised beaches in Maharashtra and Goa, which may serve as vital, if sporadic, nesting grounds.
Meanwhile, two other Olive Ridleys tagged with satellite transmitters have followed the expected migratory route from Odisha to Sri Lanka, covering about 1,000 kilometres. The contrast between these predictable movements and turtle 03233’s unprecedented journey is offering critical insights into the complex migration patterns of a species listed as Vulnerable on the IUCN Red List.
Findings from these ongoing studies could reshape conservation strategies for Olive Ridleys in India, pushing for a more integrated, coast-to-coast approach. Researchers hope the evidence will strengthen regional cooperation and encourage stronger measures against threats such as fishing, coastal development, and climate change.
As scientists continue to track turtle 03233’s remarkable odyssey, the larger lesson is clear: nature still has the power to surprise us—and the future of endangered species may well depend on how quickly we adapt and respond.