Five of the seven species of marine turtles are found in Indian coastal waters and at least four have significant nesting beaches and/or feeding areas. We are studying leatherback turtles in Little Andaman Island, olive ridley turtles in Orissa, and have initiated studies on green turtles in the Lakshadweep islands. We have been carrying out studies on population distributions through nesting beach monitoring, satellite telemetry and offshore surveys. We have also carried out studies on their feeding behaviours as well as population genetics. We have also initiated a collaborative effort with NGOs along the mainland coast to monitor temperatures, and potential impact of climate change on sea turtle populations through its impact on sex ratios.We are also actively involved in socio-ecological research on the political ecology of sea turtle conservation, conflict and their management. For a brief history of research at these locations, see here.
Olive ridley turtles in Orissa
Olive ridley turtles (Lepidochelys olivacea) are known to nest en masse only in Pacific Costa Rica and Mexico, and Orissa on the east coast of India The olive ridley population on the east coast of India is also believed to be an evolutionary source for ridleys found across the world. We initiated a long term monitoring programme for olive ridleys at Rushikulya rookery on the southern Orissa coast. We monitor solitary and mass nesting populations at this site each season; a census of the mass nesting event is carried out in collaboration with the Forest Department. We also monitor the in-water population at this rookery. We have studied the effect of light pollution on the mis-orientation of hatchlings in Rushikulya. In order to examine the impacts of climate change, we translocate nests to a hatchery to monitor nest temperature profiles and collect dead hatchlings to estimate sex ratios (we also collect temperature data and hatchlings from other site on the mainland coast in collaboration with other partners). In addition, we study the phylogeography of olive ridley turtles along the east and west coast of India.
- Karnad, D., K. Isvaran, C.S. Kar and K. Shanker (2009) Lighting the way: reducing the impact of light on misorientation of olive ridley turtle hatchlings at Rushikulya, India. Biological Conservation142: 2083 – 2088.
- Shanker, K. & R. Kutty (2005) Sailing the flagship fantastic: myth and reality of sea turtle conservation in India. Maritime Studies 3(2) and 4(1): 213-240.
- Shanker, K., J. Rama Devi, B.C. Choudhury, L. Singh & R.K. Aggarwal (2004) Phylogeography of olive ridley turtles (Lepidochelys olivacea) on the east coast of India: implications for conservation theory. Molecular Ecology 13: 1899-1909.
- Shanker, K., B. Pandav & B.C. Choudhury (2004) An assessment of the olive ridley turtles (Lepidochelys olivacea) nesting population in Orissa, India. Biological Conservation 115: 149 – 160.
- Pandav, B., B.C. Choudhury & K. Shanker (1998) The Olive Ridley sea turtle (Lepidochelys olivacea) in Orissa: an urgent call for an intensive and integrated conservation programme. Current Science 75: 1323-1328.
Leatherback turtles in Little Andaman Island
The leatherback turtle (Dermochelys coriacea) is the largest and widest ranging sea turtle. Leatherback turtle nesting in India is currently restricted to the Andaman and Nicobar Islands and very little is known about nesting trends. Since January 2008, we have monitored nesting populations on Little Andaman Island. We also profile the habitat and collect air and sand temperatures to assess the impact of climate change. We are conducting genetic analysis to study phylogeography and have also initiated a project on monitoring post-nesting movements of leatherback turtles using satellite transmitters. Of the ten turtles we tracked, many went southeast along the coast of Sumatra, some traveling as far as Western Australia. A few traveled west, reaching the coasts of Mozambique and Madagascar.
- Namboothri, N., A. Swaminathan and K. Shanker (2015) Olive ridley mass nesting at Cuthbert Bay Wildlife Sanctuary, Middle Andaman Island. Indian Ocean Turtle Newsletter 21: 7-9.
- Shanker, K. (2013) Leatherback turtles on the mainland coast of India. Indian Ocean Turtle Newsletter 17: 15-17
- Shanker, K. and N. Namboothri (2012) Sea turtle surveys and research in the Andamans and Nicobar Islands. Indian Ocean Turtle Newsletter 16: 1-3.
- Namboothri, N., A. Swaminathan and K. Shanker (2012) A compilation of data from Satish Bhaskar's sea turtle surveys of the Andaman and Nicobar Islands. Indian Ocean Turtle Newsletter 16: 4-13.
- Namboothri, N., A. Swaminathan and K. Shanker (2012) Post-nesting migratory routes of Leatherback Turtles from Little Andaman Island. Indian Ocean Turtle Newsletter 16: 21-23.
- Fatima, E., H. Andrews, S. John & K. Shanker (2011) Status of Marine Turtles in Cuthbert Bay, Middle Andaman Islands. Marine Turtle Newsletter 130: 6-9.
- Swaminathan, A., N. Namboothri and K. Shanker (2011) Post-tsunami status of leatherback turtles on Little Andaman Island. Indian Ocean Turtle Newsletter 14: 5-9.
- Shanker, K., N. Namboothri and A. Swaminathan (2011) Tracking the voyage of the leatherback: the research programme in the Andaman Islands. Survey of the Environment 2010: 79-82.