Long-term monitoring of sea turtles at the Rushikulya mass nesting rookery, Odisha
Rushikulya, in southern Odisha, is one of three mass nesting rookeries for olive ridley sea turtles in Odisha. These sites represent the only mass nesting beaches for ridleys outside central America. Dakshin’s researchers have been associated with this area over the past decade, conducting biological research and training of community-based conservation organisations, local youth groups, and forest department staff. This site has been monitored regularly since 2007 when a comprehensive long-term monitoring project was initiated with the following broad objectives:
- To monitor sea turtle populations at this site through a census of mass nesting events, mortality and hatching success
- To monitor environmental change by monitoring temperatures and beach profiles
- To train local organisations and Odisha Forest Department staff in undertaking long-term scientific monitoring of the turtle population, shoreline changes, and climate change impacts
Regular monitoring of the nesting beach has been carried out over the last 10 years. All mass nesting events during this period have been censused using a standard technique that can be compared with other sites worldwide. Research has also focused on the possible impacts of climate change on hatchling sex ratios, since sex is determined by incubation temperature in sea turtles. Approximately 30 nests are relocated to a hatchery each year to monitor incubation temperatures (using data loggers) and to collect dead hatchlings for sexing.
In 2010, offshore monitoring of turtle congregations was initiated using transect-based methods. In-water surveys provide information about the location and movement of turtle congregations, and an alternate metric for assessing long-term trends in populations.
In addition, we interact regularly with the local forest department and conduct training programmes for their field staff on methods of carrying out the mass nesting census and for the maintenance of hatcheries. A pictorial manual has been produced to assist field and forest department staff in carrying out the census.