Bageshri holidaying with Odisha olive ridleys off Sri Lanka coast

Bageshri, the satellite-tagged turtle her course as of Friday

Having completed two orbits off the southern coast of Sri Lanka, the satellite-tagged turtle Bageshri is now 200 km off the eastern coastal city of Kalmunai in Sri Lanka. Interestingly, the area where Bageshri is now is also the spot where ‘arribada' nesting turtles from Odisha are at this point in time. Virendra Tiwari, director, Wildlife Institute of India (WII) said, "The straight-line distance travelled by Bageshri is around 2,000 km and Guha [another turtle] is 750 km from Guhagar [in Ratnagiri] where both of them were satellite-tagged in February this year."

On the night of February 21, the WII team, Mangrove Foundation and the Maharashtra forest department's Ratnagiri division patrolled Guhagar beach, and Bageshri and Guha, two female olive ridley turtles, were restrained after they had nested. On the morning of February 23, the turtles were returned to the sea after the WII team had fitted them with satellite transmitters. Dr R Suresh Kumar, scientist, department of endangered species management, WII and his team have been tracking the interesting journey of the turtles.

He said, "Tracking data is making it clear that we are possibly dealing with two populations of the olive ridley turtles now. The solitary nesting olive ridley turtle population that arrives at the west coast of India has two populations: one that is resident to the Arabian Sea and the other is the migratory population which might be from Sri Lankan waters or even beyond that."

"As of Friday, Bageshri has gone further east of Sri Lankan waters. This clearly tells us that there are olive ridley turtle populations from other ocean basins coming to the west coast of India. There are resident and migratory populations and the movement of each will be different from each other. The resident population will be very slow in its movement and it shows a lot of cyclic movements. If we see the track of Bageshri it is more consistently straight which also hints towards the fact that she knows where she is heading. Whereas the Guha's movement is more cyclic, which hints that she is exploring their area," Dr R Suresh Kumar said.

WII scientists believe more interesting updates may emerge in the coming days.

On July 23, the transmission from the tag fitted on Guha stopped due to technical reasons but on Thursday it started functioning again and it was learnt that she was in northern Kerala waters.

Dr R Suresh Kumar also told mid-day that this time of the year happens to be peak monsoon season when most of the olive ridley turtles are down in Sri Lankan waters, including the ones arriving from the Odisha coast.

"In fact, what is interesting is that the area, where Bageshri currently is at, is also the area where arribada nesting turtles from Odisha are at, even as we speak, so there is a mixing of turtle populations. It is generally believed that they all intermix but when it comes to breeding, they will go back to their respective places. Their return migration will only start in October," he said.

What is arribada?
Every year, at Odisha's Gahirmatha Marine Sanctuary, the phenomena known as arribada - the mass nesting of olive ridley sea turtles - begins. This year, a record-breaking number of female turtles - more than 6.3 lakh - have gathered at Rushikulya beach in Odisha's Ganjam district to mass nest.

750 km
Straight-line distance travelled by Guha