Distribution : Lakshadweep

Nesting species:

Non-nesting species: leatherback (rare)

Overview:

Lakshadweep, a part of Laccadive-Chagos ridge, consists of three island groups – Laccadives, Minicoy and Amindivi. It has a coastline of 132 km and a lagoon area of 4,200 sq.km.

Green and hawksbill turtles are commonly seen in the lagoons while olive ridleys are found to nest on these islands. Leatherback turtles are rarely sighted by fishermen, but do not nest in this region.

Interesting Story:

One of Satish Bhaskar’s surveys in the Lakshadweep (1982) was a tale of daring and adventure. During this survey, he had himself dropped off for several months on the island of Suheli Valiyakara. He marooned himself on the island from May to September, which was during the monsoons, to monitor green turtle nesting. Satish launched a message for his wife back in Madras (Chennai) in a bottle on July 3rd and threw it in the waters with an intension of studying ocean currents. 24 days and more than 800 km later it was picked up by a Sri Lankan fisherman, who very kindly posted it to his wife along with a covering letter, a family picture and an invitation to visit him in Sri Lanka.

History

Satish Bhaskar initiated turtle surveys in Lakshadweep as in many other places in the country in the late 1970s. He found that unlike other places in India, green turtles were abundant in the Lakshadweep archipelago. Green turtles foraged on the copious seagrasss in the region. He also found nesting on inhabited islands of Minicoy, Agatti, Kadmat and Androth and counted over 200 turtle nests on an uninhabited island called Suheli Valiyakara (Bhaskar 1978).  

Threats to sea turtles in Lakshadweep were of a different nature than that on the mainland. There was no consumption of meat or eggs, but green turtles in the lagoon were harpooned for their fat to be used for caulking boats or their shells sold to traders on mainland India. He also found juvenile hawksbills killed, stuffed and sold to tourists on the mainland (Bhaskar 1978).

In 2001, Basudev Tripathy found that the practice of stuffing turtles continued since Bhaskar’s surveys and a stuffed specimen could fetch about Rs.500/- to Rs.1500/- on the mainland coast of Mangalore, Calicut or Cochin (Tripathy 2002). Since Lakshadweep has a long history of pole and line fishing for tuna, the cases of incidental mortality have been very low.

Research

The Madras Crocodile Bank Trust (MCBT) first published studies on the status, distribution and threats to sea turtles in Lakshadweep from a survey in 1978 (Bhaskar 1978). Nearly two decades later, in 2001, Basudev Tripathy of the Wildlife Institute of India (WII) surveyed the islands as a part of Government of India-UNDP project. Tripathy’s data showed an extensive green turtle foraging population on the islands, with the relative abundance of green turtles being much higher in Agatti than the other islands (Tripathy, Choudhury and Shanker 2002).

Tripathy interviewed the local residents and fishers about nesting patterns and found that their description was similar to his field surveys. Green turtle nesting was higher in uninhabited islands and most abundant in Suheli; similar to the patterns described by Bhaskar during his surveys in 1978.

Rohan Arthur finished his PhD on coral reefs in Lakshadweep and continued his long-term monitoring of reefs. Simultaneously, he initiated a study of herbivory in seagrass communities in the lagoons. He observed that a large number of green turtles were foraging seagrass. He learnt that the fishers in the area believed that the population-rise of green turtles was due to the protection they received through conservation efforts, which led to a decline in their fish catch. They strongly believed that the turtles were a major factor in the decline of seagrass patches in the lagoon depriving fish of feeding, breeding, and resting grounds. The fishers were also of the opinion that the turtle population was initially controlled due to the occasional hunting for their fat, which was used as caulking in boats.

Arthur’s team started monitoring the abundance of turtles in 2005. He recorded larger numbers in Agatti in comparison to Kavaratti and Kadmat. Aparna Lal, a master’s student from WII working under B.C. Choudhury, collaborated with Arthur to study the effect of green turtles on seagrass meadows. The results of these studies showed that green turtles severely affected the seagrass meadows and thus modified the ecosystem (Lal et al. 2010).

Nachiket Kelkar, who joined Arthur’s team to survey the green turtles, found that the numbers in Agatti had dropped while the numbers in Kavaratti, Kadmat and other locations increased dramatically. It appeared that the turtles were foraging seagrass patches until they had declined severely and then moving to other lagoons.

In early 2013, Bharti D.K., Kartik Shanker’s student from the Centre for Ecological Sciences, IISc, set out to study the foraging ecology of green turtles in Lakshadweep. Her work aimed at understanding the role of seagrass in green turtle distribution. In 2016, as a follow up to Bharti’s study, Meenakshi Poti of Dakshin Foundation mapped the seagrass distribution across two island lagoons and investigated the diet selection of green turtles by studying their faecal matter. The results of this study showed that the seagrass density and green turtle numbers were low in Agatti, whereas Kalpeni, where seagrass densities were higher, had seen a rise in the number of turtles.

The teams from Dakshin Foundation and Nature Conservation Foundation continue to monitor green turtles and seagrass in the islands to understand the long-term dynamics of the species and ecosystem.

 

Conservation

The Lakshadweep Marine Resource and Conservation Centre (LMRCC) was started by Jafer Hisham and Mohammed Babu in 2008 with a vision to achieve “a sustainably progressing Lakshadweep, where marine ecosystems are healthy and well managed”. Their conservation efforts are mostly centred around birds, sea turtles, environmental education and the empowerment of fishermen. They collaborate with various organizations on the island as well as mainland India to promote marine conservation.  

Seagrass beds at Kalpeni island

Photo: Mahima Jaini

Hawksbill turtle at Kavaratti

Photo: Mahima Jaini

Key figures in sea turtle research and conservation in Lakshadweep

Basudev Tripathy

Kartik Shanker

Nachiket Kelkar

Rohan Arthur

Satish Bhaskar

Sources and References

Source:

Shanker, K. 2016. From soup to superstar. HarperLitmus India.

Tripathy, B., B.C. Choudhury and K. Shanker. 2006. Sea turtles of Lakshadweep archipelago, India. Marine turtles of the Indian subcontinent (eds. Shanker, K. and B.C. Choudhury). Pp. 119–136. Universities Press (India) Private Ltd.

References:

Bhaskar, S. 1979. Marine turtles in India’s Lakshadweep islands. Madras Snake Park.

Lal, A., R. Arthur, N. Marbà, A.W. Lil, and T. Alcoverr. 2010. Implications of conserving an ecosystem modifier: increasing green turtle (Chelonia mydas) densities substantially alters seagrass meadows. Biological Conservation 143(11), 2730-2738.

 

Kelkar, N., Arthur, R., Marbà, N. and Alcoverro, T. (2013), Greener pastures? High-density feeding aggregations of green turtles precipitate species shifts in seagrass meadows. J Ecol 101: 1158–1168. doi:10.1111/1365-2745.12122

Kelkar, N., T. Alcoverro, M.K. Ibrahim, M. Gangal and R. Arthur. 2014. Long-term tracking of conflict between green turtles and fishers by community-based seagrass monitoring in the Lakshadweep Islands, India. Final report submitted to the Rufford Small Grants Foundation, U.K. 21 p. (Nature Conservation Foundation, Mysore)

Tripathy, B. 2002. Marine biodiversity of Lakshadweep- An overview. Kachhapa 7: 14-19.

Tripathy, B., B.C. Choudhury and K. Shanker. 2002. A survey of marine turtles and their nesting habitats in the Lakshadweep islands, India. A GOI-UNDP sea turtle project report. Wildlife Institute of India, Dehradun, India. 62

Tripathy, B., K. Shanker and B.C. Choudhury. 2006. The status of sea turtles and their habitats in the Lakshadweep archipelago, India. Journal of the Bombay Natural History Society 103(1): 33–43.