According to senior scientist of Marine Programme of WII, Dehradun, Dr Shiva Kumar Kuppuswamy, in April 2001, the Forest Department and WII along with biologist Jack Frazier of Smithsonian Institution, had fitted PTTs on four turtles at Devi beach. “The turtles circled the waters and only one of them migrated towards Sri Lanka,” The New Indian Express (TNIE) quoted him as saying.
In 2017 again, WII had fitted PTTs on 30 turtles. Many of them were seen moving towards Sri Lanka. However, the PTTs stopped transmitting within a year, either due to technical issues or the death of turtles in trawler-related mishaps, the report added.
During the mass nesting of turtles, WII will fit the transmitters on 10 turtles at Gahirmatha Marine Sanctuary in Bhitarkanika National Park. Similarly, 10 PTTs will be fitted on turtles at Rushikulya beach and as many at Devi beach, Dr Kuppuswamy told TNIE.
How do PTTs work?
- The base of the transmitters and the anterior part of the carapace is covered with epoxy (adhesive).
- The PTTs have temperature sensors and surface time counters to indicate the time spent by the turtles on land.
- The batteries of the transmitters last a year if a turtle spends 30 per cent of its time on surface.
- The data received from the device will be analysed and mapped at WII.
- Satellite transmitters send high-frequency signals that are received by polar- orbiting weather satellites.
- The transmissions are first decoded to identify the transmitter, as each has a unique code.
- The latitudes and longitudes can be plotted on a map and the migratory routes of the turtles traced, added the scientist.