A journey of a thousand miles begins with a single step, so goes the saying. In the case of the Olive Ridley turtle known as “03233”, it began with a flap of her flippers. These were no ordinary flippers, but had been tagged in 2021, on the east coast of India. And to the amazement of researchers, the turtle swam all the way to the opposite coast to lay her eggs, which is when her story came to light.
On January 27 this year, under the crescent moon with the tide rising, the local turtle nest managers of Maharashtra’s Mangrove Foundation, Sanjay Bhosle and Shardul Todankar, started out on their routine patrol to look for nesting turtles at the Guhagar beach in Ratnagiri district. Soon they encountered a nesting turtle on the beach. After waiting for her to finish nesting, they approached her to flipper tag—and discovered that someone had already done it. The tag read “03233” and on the underside, it read “ZSI N.A.P.O. KOL-53. IN DIRECTOR@ZSI.GOV.IN”, from which they found that the turtle had been flipper-tagged on the east coast of India, in Odisha, in 2021 by researchers from Zoological Society of India (ZSI).
The tag helped researchers from the Wildlife Institute of India (WII) and the mangroves cell of the Maharashtra Forest Department understand the journey undertaken by 03233.
The turtle’s journey of at least 3500 kilometres is remarkable because while it is established that Olive Ridley turtles (Lepidochelys olivacea) nest across multiple beaches in a season or across years, this turtle nesting across two ocean basins is the first such known record.
Olive Ridleys are one of the most abundant sea turtle species in India, and nest all along the Indian coastline including the islands. Interestingly, the species adopt two different nesting strategies: nest en masse in thousands at select beaches in Odisha, and also nest solitarily along the coast.
Despite legal protection, Olive Ridley turtles remain highly threatened. The species is classified as Vulnerable under the IUCN Red List and is protected under Schedule I of India’s Wildlife Protection Act, 1972, according them the highest level of protection. However, fishing-related mortality continues to pose a severe challenge, resulting in hundreds of turtles washing ashore dead every year.
Several efforts to mitigate the threats to turtles are currently underway, and one of the approaches for long-term monitoring of turtle populations is flipper-tagging. This passive and cost-effective method involves attaching a small metal tag on the inner end of the fore-flippers. The tag has a number inscribed on one side for individual turtle identification, with contact details on the underside.
It was later learnt that the turtle carrying the tag was an individual tagged by a research team of the Zoological Survey of India (ZSI), while mass-nesting at the Gahirmatha beach in Odisha on March 18, 2021.
Dr Basudev Tripathy, Senior Scientist at ZSI, who is undertaking the flipper-tagging study in Odisha said that the turtle 03233 had been tagged along with over 15,000 other turtles along Odisha’s coast. “Little did I imagine that the turtle would move to the west coast of India, from the Bay of Bengal to the Arabian Sea,” said Dr Tripathy.
Dr Suresh Kumar, Senior Scientist at WII, was equally surprised at the finding of the turtle. Talking to mid-day Dr Kumar said, “This is indeed very important information, that the turtles which arrive to nest solitarily along the Maharashtra coast do also join in to mass-nest along the Odisha coast. This turtle has travelled at least 3,500 km from the Odisha coast to Guhagar, circumnavigating the southern tip of India.”
It is likely that we are dealing with different populations, Dr Kumar said, with some moving between the two coasts and adopting different nesting strategies, while others remaining faithful to a particular ocean basin and showing site-fidelity to a specific nesting beach.
For decades it had been thought that nesting turtle populations on India’s east and west coasts are separate, with no known interconnections, Dr Tripathy said, adding that the flipper-tagging effort had shown this to be wrong.
The Mangrove Foundation with WII support has begun flipper-tagging nesting turtles along the Ratnagiri coast to arrive at estimates of nesting turtle populations. Turtles are known to nest multiple times in a season, and so without individual identification the true estimate of the population can never be known.
SV Ramarao, Additional Principal Chief Conservator of Forests (APCCF) of the mangroves cell and Executive Director, Mangrove Foundation said, “The flipper-tagging of nesting turtles along the Maharashtra coast recently launched by the Mangrove Foundation along with WII is likely to help us understand the Olive Ridley turtle populations better.”
Deputy Director of the Mangrove Foundation Dr Manas Manjrekar told mid-day that while many questions remain unanswered, one thing is certain—the story of this turtle has rewritten what scientists thought they knew about Olive Ridley migration. “And for the nest managers, researchers, and conservationists who witnessed this discovery firsthand, they are not just observers of history; they are now part of it,” he said. “This turtle’s journey has become a testament to the boundless mysteries of the sea and it’s a story that will be studied, debated, and told for generations to come.”
3500
Kilometres that Olive Ridley turtle 03233 is believed to have swum
45 to 60
Days it takes for eggs to hatch
Turtle nesting facts
A female turtle lays between 100 and 150 eggs at a time.
Did you know?
Sea turtles play a crucial role in maintaining ocean ecosystems. They help sustain seagrass beds and coral reefs, contribute to nutrient cycling, and provide habitat for other marine life. A decline in sea turtle populations weakens these essential functions, affecting overall ocean health.
Action plan
Approximately 40,000 to 11,00,000 turtles nest on Indian beaches annually, though nesting numbers vary each year.
Graphic/Aparna Chaudhari
. MOEF&CC has developed a National Marine Turtle Action Plan (2021-2026) to conserve marine turtle species and their habitats. The plan aims to reduce threats to turtle survival, enhance research and monitoring, raise awareness about conservation, promote sustainable ecotourism and strengthen national, regional, and international cooperation. Indian coastal waters support five of the world’s sea turtle species: the olive ridley (Lepidochelys olivacea), green (Chelonia mydas), hawksbill (Eretmochelys imbricata), leatherback (Dermochelys coriacea), and loggerhead (Caretta caretta). They are protected under the Wildlife (Protection) Act, 1972. India is home to the largest known nesting population of olive ridley turtles. Except for loggerheads, the other four species nest along the Indian coastline and islands.
. Additionally, the success of sporadic nests has been declining due to predation and habitat degradation.
. According to forest department officials, there are six nesting beaches in Sindhudurg, four in Raigad, and 13 in Ratnagiri. The nesting season runs from November to March each year.
