KENDRAPARA: Two satellite-tagged Olive Ridley sea turtles have travelled around 1,000 kilometers to reach north of Sri Lanka sea within a month from Gahirmatha Marine Sanctuary in Odisha’s Kendrapara district.
Scientists of the Wildlife Institute of India (WII) in collaboration with Forest department had fitted satellite transmitters or platform transmitter terminals (PTT) on two female Olive Ridleys on March 12 on Gahirmatha beach during the mass nesting to track their routes.
Both the turtles were found to have travelled around 1,000 km to reach Sri Lanka seawater till date. “We have been monitoring movements of the satellite transmitters fitted turtles every day,” said Dr Suresh Kumar, senior scientist of WII on Thursday.
Ocean currents are like highways in the sea, and sea turtles are expert navigators which use these currents for their journey. Olive Ridley turtles each year arrive at Odisha coast for mass nesting and mostly travel in Bay of Bengal from Odisha to Sri Lanka but never travel to the Pacific Ocean, he said.
“Sri Lanka became the first country in Asia to completely ban bottom trawling and the use of destructive trawl nets in 2017 as a result, seawater is now the safe haven for sea turtles,” added Dr Kumar.
Experts say most sea turtles migrate between foraging and nesting grounds. Both male and female turtles migrate to nesting areas to breed, generally in the area where they were born with the help of ocean currents and the earth’s magnetic field.
Each year, large numbers of turtles die after being entangled in the fishing nets of the trawlers. The PTT are attached to the animals whose movements are to be studied.
In April 2001, for the first time, Forest Department and WII fitted four turtles with PTTs at Devi beach permitting an online monitoring of migratory routes. The PTT-fitted turtles circled the waters, and only one was seen to migrate south towards Sri Lanka, as per the tagging result.
In 2007, the Forest department fitted PTTs on 30 more turtles in Odisha and many turtles moved towards Sri Lanka, said Dr Basudev Tripathy, a wildlife biologist and the officer in charge of western regional center of the Zoological Survey of India, Pune.