Journal of Entomology and Zoology Studies 2013; 1 (6): 11-14

Sea turtle exploitation from , Southeast coast

ISSN 2320-7078 of JEZS 2013; 1 (6): 11-14 © 2013 AkiNik Publications Received 21-10-2013

Accepted: 01-11-2013 K. Chandrasekar, M. Srinivasan

ABSTRACT The Present observation was carried out on sea turtles along the southeast coast of Tamil Nadu during K. Chandrasekar June 2012 to May 2013. Curved Carapace Length (CCL) and Curved Carapace Width (CCW) were Centre of Advanced Study in Marine measured when the carapaces of dead turtles were found intact. Data on exploitation of turtles were Biology, Faculty of Marine Sciences, collected by regular observations of turtle carapaces found near ditches, unused buildings and inside Annamalai University, Parangipettai, thickets that bordered the coastline. The average size of encountered green turtles was 92.4 cm CCL Tamil Nadu, India (SD±14.6) and 88.3 cm CCW (SD±15.4). The mean size of olive ridley carapaces was 80.2 cm CCL Email: [email protected] (SD±10.0) and 77.13 cm CCW (SD±11.16). For hawksbills, CCL was 68 cm (SD±10.4) and CCW was 60.33 cm (SD±13.8). Green, olive ridley and hawksbill turtles show an exploitation ratio of M. Srinivasan 61.9%, 34.2% and 3.9% respectively during the June 2012 to May 2013. Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Keywords: Exploitation, observation, sea turtles, carapace, size, mean. Annamalai University, Parangipettai, Tamil Nadu, India Abbreviation: Curved Carapace Length (CCL), Curved Carapace Width (CCW) Email: [email protected]

1. Introduction Marine turtles have swum in the world’s oceans for over 100 million years. The only widely distributed marine reptiles, many species migrate for thousands of kilometres and even across entire oceans between feeding and nesting grounds. An integral part of coastal and

marine ecosystems, they have also been fundamental to the culture of coastal societies for millennia. But human activities over the past 200 years have massively tipped the scales against the survival of these ancient mariners[21]. Today there are seven species of marine

turtles in the world. Four of them were observed on the coast of Tamil Nadu and in the region (Chelonia mydas - green turtle; Eretmochelys imbricata - hawksbill; Lepidochelys olivacea - olive ridley; Caretta caretta - Loggerhead turtle). The Indian Ocean offers therefore a good environment as a habitat for turtles. Thus, the turtle can be regarded as the emblematic animal of the region. Where she herself was born to lay its eggs! It is therefore

essential to preserve the nesting sites of turtles. The feeding sites of turtles are coral reefs, lagoons and sea grass (a sort of marine prairie). Slaughtered in the millions for their eggs, meat, skin, and shells, their already reduced populations still suffer from poaching and over-exploitation, as well as incidental capture in fishing gear and habitat loss and alteration. Today, six of the seven living species are classified as Endangered or Critically Endangered. Concerted conservation efforts have seen

turtle populations recover in some areas, but without urgent global action the future of these [21] magnificent animals look increasingly grim . Sea turtles have been used for local consumption since time immemorial providing food (oil and protein) as well as other commodities (bone, leather and shell) to coastal people around the world[18]. Their shells are widely used for the production of various curios. There are four species of sea turtles found in the [11]: green (Chelonia mydas, local name: Paer aamai), olive ridley (Lepidochelys olivacea, local name: Yeth aamai), leatherback

Correspondence: (Dermochelys coriacea, local name: Ezhuvari aamai) and hawksbill (Eretmochelys K. Chandrasekar imbricata, local name: Kilimooku amai). Turtle fishing was practised in this region for ages Centre of Advanced Study in Marine and chelonians were exported to and other countries until a couple of decades ago Biology, Faculty of Marine Sciences, [1, 8]. Prior to 1972, there was legal live turtle trade between India and Sri Lanka. Live turtles Annamalai University, [2] Parangipettai, Tamil Nadu, India were transported by sailing boats from , Tamil Nadu to Jaffna, Sri Lanka and turtle Email: [email protected] shells were exported to France, U.K. and several other European countries. Tel: +91 9944471404

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In 1960, it was estimated that an average of about 3000 to 4000 Endangered Species of Wild Fauna and Flora (CITES) has turtles were landed every year in the Gulf of Mannar area and 1000 prohibited all international commercial trade in marine turtles since turtles in the ; green turtles formed 75% of the landings, they were listed on Appendix I of the Convention in 1981. Over a and olive ridley and loggerhead formed 20%[10]. The turtle trade period of years, CITES has been a powerful tool in reducing was stopped in the early 1980s. The Indian Wildlife Protection Act international turtle commerce, but its restrictions have no legal (1972) lists all species of marine turtles in Schedule I, thereby effect on domestic trade. Some countries however have imposed giving them the highest degree of protection. more strict domestic measures, in response to the conservation status of the species, and the heightened awareness produced by the 1.1 Accidental catch Appendix I listings. The participation of local communities and the The operation of trawlers in this area not only increased fish catch need to incorporate conservation in socioeconomic development but also resulted in a substantial increase in the accidental catch and are both critical to the success of marine turtle conservation in the mortality of sea turtles. A recent study of sea turtles off the Tamil developing world, because exploitation of turtles is often driven by Nadu coast revealed that fishing is one of the major causes of turtle a lack of economic alternatives. Programmes which can provide mortality there[4]. Although rates of accidental catches of sea turtles economic alternatives to exploitation and wellbeing to are relatively high in this area, most of them go unreported or communities demonstrate that turtles are ultimately more valuable unnoticed. Accidental catch of olive ridleys, Lepidochelys olivacea, alive than dead. Education and outreach are crucial to changing was reported at Pamban[13] and off Dhanushkodi[14]. The accidental attitudes and instilling a conservation ethic that will be sustained catch of leatherback turtles, Dermochelys coriacea, was reported over time[7]. from Dhanushkodi[14], [15] and [19]. Due to more attention in recent times to the conservation and management 2. Methodology of sea turtles[9], the stranding of turtles has been reported more 2.1 Study area frequently[12]. The present study observations on the exploitation of various Recently, another threat has emerged in the form of dynamite species of sea turtles along the Southeast coast of Tamil Nadu, fishing along the 19 km Rameswaram to Dhanushkodi coast. Kovallam (N12°47.357'), Mahaballipuram (N12°37.105'), Dynamite fishing is practiced to catch fish, particularly soles, along Pudhucherry (N11°55.386'), Cuddalore OT (N11°43.315), the coast of Tamil Nadu and Kerala. Dynamite fishing in the Parangipettai (N11°31.602'), Poombuhar (N11°08.685'), Karaikkal Chaliyar River, north Kerala was reported[17]. Dynamite fishing is (N10°54.938'), Nagapattinam (N10°44.694'), Kodiakarai regularly practiced in the Rameswaram area, which often causes (N10°16.481'), Rameswaram (N09°16.573'), Dhanushkodi the death of endangered species, such as dolphins and sea turtles. (N09°11.930'), Mandapam (N09°16.611') and Punnakayal (N- Regular and continuous dynamite fishing operations caused the 8°38’13.10”, E-78°6’56.90”) from June 2011 to July 2012. death of more than 10 turtles which were washed ashore during the end of January 2004 along the Rameswaram to Dhanushkodi coast. 2.2 Field methods Tens of thousands of marine turtles are killed deliberately each year Turtle mortality was estimated through direct observation of dead in the developing world as a source of protein and cash revenue. turtles washed ashore and from reports published in the Poverty and cultural mores, coupled with weak (or non-existent) newspapers. Curved Carapace Length (CCL) and Curved Carapace governance and enforcement, contribute to this problem. Width (CCW) were measured when the carapaces of dead turtles Exploitation is particularly serious in parts of Asia and the Western were found intact. Data on exploitation of turtles were collected by Pacific where tens of thousands of green turtles are killed for food regular observations of turtle carapaces found near ditches, unused each year. Along the Eastern Pacific coast of Mexico, despite buildings and inside thickets that bordered the coastline. Monthly complete protection, green turtles are still very much at risk from observations in the above areas were made carefully to determine continuing exploitation. A voluminous, legal, commercial harvest the extent of mortality of turtles. Turtles usually get caught in ray of green and hawksbill turtles by the Wayuu community persists in nets, locally known as thirukka valai[3], which are similar to the the Caribbean shores of Colombia. And over 10,000 green turtles pachuvalai gillnets[16]. In the study area, gillnets were mostly used are harvested each year along the Miskito coast of Nicaragua. In for fishing. Gillnets are set in shallow waters and left for about 8 - the Pacific islands, increases in exploitation accompanied the 10 hours. Turtles that are entangled in the nets commonly die, decline in traditional taboos on turtle hunting, which has either due to asphyxiation, or the fishermen chop off the flippers significantly reduced turtle populations. In West Africa eggs are and/or club the head of live entangled turtles, to remove them from collected and marine turtles are killed for food, medicine and use in the net[5]. During monthly patrols, each encountered carapace was voodoo ceremonies. Egg collection on many turtle nesting beaches assigned to a species using key characters such as the number and is also a very serious threat, especially in Southeast Asia where a pattern of scutes and their colouration; they were measured to the culture of legal egg collection leads to the removal of tens of nearest cm for curved carapace length (CCL) and curved carapace thousands of eggs a practice which has contributed to the local width (CCW) using a flexible tape. The location of the carapace extinction of leatherbacks in Malaysia. Within the last several was noted. Then it was photographed and tagged with paint. Those decades extensive egg collection and the killing of adult turtles in carcasses found in ditches were also visually counted and identified Indonesia has resulted in huge population declines throughout the and data noted on the location where it was found (Fig 1). archipelago. Despite protective legislation, many eggs produced Additional information about the incidental capture of turtles was each year in Central America are still collected for subsistence or obtained through informal discussions with fishermen and other commercial use. Hunting and egg collection continue throughout members of the local community. the Indian Ocean. The Convention on International Trade in

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Fig 1: Carapace and Skull of the olive ridely turtle All marine turtles, including their eggs, are listed in Appendix I of the beach, the number of old skulls that were more than one night the Convention on International Trade in Endangered Species of old and the estimated size of the turtle exploitation for the beaches Wild Fauna and Flora (CITES) making any commercial trade with recorded turtle during survey are summarised below. across international borders illegal. Marine turtles are increasingly The average size of encountered green turtles was 92.4 cm CCL threatened by poaching of their eggs for commercial sale. Meat and (SD±14.6) and 88.3 cm CCW (SD±15.4). The mean size of olive shells of marine turtles, as well as whole stuffed specimens, are ridley carapaces was 80.2 cm CCL (SD±10.0) and 77.13 cm CCW also illegally sold. (SD±11.16). For hawksbills, the mean CCL was 68 cm (SD±10.4) and CCW was 60.33 cm (SD±13.8). Green, olive ridley and 3. Results and Discussion hawksbill turtles show an exploitation ratio of 61.9%, 34.2% and Exploitation of three species of marine turtle was identified during 3.9% respectively during the study period from June 2012 to July the two sets of surveys: olive ridley, C. mydas and Caretta caretta. 2013. Agastheesapillai[1] Reported that green turtles constituted The number of fresh skulls from the night preceding the survey of 89% of all turtles caught in the Gulf of Mannar and Palk Bay during 1971 and 1976.

Fig 2: Green turtle shows more exploitation during the study period

Green turtles were observed every month, with a peak in mortality along the Southeast coast of Tamil Nadu. Most of the fishermen and exploitation (Figure 2). Olive ridley turtles were also captured confirmed that those turtles that were entangled in nets and were nearly every month, with a peak in August. As reported by local still alive were taken for consumption. Sea turtle populations in this fishermen, olive ridleys substituted for the unavailability of greens. area have been reported to have declined due to their over- The abattoir of turtles was opened mostly on Sundays. Turtle meat exploitation for trade and from accidental drowning in fishing gear price ranged from Rs. 120–150 for green turtles and Rs. 100–120 such as gillnets and trawlers[2]. This study therefore recommends for olive ridleys. Hawksbills were not consumed because the local that government officials should periodically check whether people were fearful of being poisoned by the meat[6]. During this fishermen use TEDs (Turtle Excluder Devices) in their fishing study, out of three hawksbill turtles, two were hit by propellers and nets. Moreover, the state fisheries department and forest one was caught in a net. But in the case of greens and olive ridleys, department must ensure strict enforcement of the law in this regard. all of them were caught in fishing nets. Some people in the area Unless this is done, it will not be possible to stop the exploitation reported that turtle meat and blood cured diseases such as piles and of turtles in the Tamil Nadu coast (especially in Rameswaram, tuberculosis. Mandapam and Tuticorin). This study reveals the pattern of current exploitation of sea turtles

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4. Conclusions K). Smithsonian Institution Press, Washington DC, USA, As sea turtle populations decline, so does their ability to perform 1982, 356–372. vital roles in maintaining the health of the world’s oceans. Death, 12. Kasinathan C, Palanichamy A. On two species of marine Exploitations and injury in commercial fisheries, loss of important turtles stranded at Mandapam. Marine Fisheries Information habitat, pollution and climate change are among the many human- Service T&E Series 2002; 171:10. caused threats pushing sea turtles towards extinction. More 13. Kasinathan C. Olive ridleys landed at Pamban proactive conservation measures are needed to protect sea turtles reported. Marine Fisheries Information Service T&E and rebuild their populations to healthy levels so they can fulfill the Series 1988; 84:10. full extent of their historic roles in ocean ecosystems. At historic 14. Krishna PS, Kasinathan C. On two species of marine turtles levels, sea turtles will help restore the health of our oceans and caught Dhanushkodi, Gulf of Mannar. Marine Fisheries make them more resilient to future threats[20]. The following actions Information Service T & E Series 1989; (102):17-18. must be taken to protect and restore sea turtle populations: 15. Krishna PS, Badrudeen M, Bose M. On the leatherback turtle • Reduce sea turtle interactions and mortalities in commercial Dermochelys coriacea landed at Rameswaram. Marine fisheries. Fisheries Information Service T & E Series 1995; 140:11. • Protect key habitat areas on land and in the water 16. Kuriyan GK. Turtle fishing in the sea around Krusadai • Pass comprehensive legislation that establishes a system to Island. Journal of the Bombay Natural History Society 1950; protect and restore sea turtle populations (49):509-512. 17. Lal MRS. Dynamite fishing in Chaliyar river, north 5. Acknowledgement Kerala. Marine Fisheries Information Service T & E We would like grateful and thank to the Dr. K. Kathiresan, Dean Series 1991; (1):21-23. and Director, Centre of Advanced Study in Marine Biology, 18. Mohanraj T. Observations on the exploitation of sea turtles Faculty of Marine Sciences, Annamalai University for providing along the Tuticorin coast, Tamil Nadu, India. Indian Ocean amenities throughout the present study. Turtle Newsletter 2011; (14):9-11. 19. Rao PVR, Jayaprakash AA, Ramamoorthy M. On the 6. Reference leatherback turtle caught from Palk Bay off Mandapam. 1. Agastheesapillai A, Thiagarajan R. Biology of the green turtle Marine Fisheries Information Service T & E Series 1989; 95:9. Chelonia mydas in the Gulf of Mannar and Palk Bay. J Mar 20. Wilson EG, Miller KL, Allison D, Magliocca M. Biolo Assn India 1979; 21(1&2):45–60. Oceana.org/sea turtles, 2006. 2. Agastheesapillai A. Turtle export from south east coast of 21. WWF. Species fact sheet: Marine Turtles Ancient mariners India during 1945-64 periods. Marine Fisheries Information threatened with extinction 2006, 1-4. Service T & E Series 1996; 142:17. 3. Bhupathy S, Karunakaran R. Conservation of olive ridley sea turtle Lepidochelys olivacea (Reptilia/ Chelonia) along the Nagapattinam coast, Southeast coast of India. Indian Journal of Marine Science 2003; 32(2):168–171. 4. Bhupathy S, Saravanan S. A report on the status of sea turtles on the Tamil Nadu coast. In: Proceedings of the National Workshop for the Development of a National Sea Turtle Conservation Action Plan 2002, 70-73. 5. Bhupathy S, Vijay M, Nixon AMA, Subramanean J, Karunakaran R, Gokulakrishnan J. The status of sea turtle populations on the Tamil Nadu and Kerala coasts. In: Monitoring and networking for sea turtle conservation in India: A UNEP CMS project report (Eds. Shanker K, Andrews H). Centre for Herpetology/Madras Crocodile Bank Trust, Tamil Nadu 2006, 58-70. 6. Das I. Turtles and Tortoises of India. Oxford University Press, Bombay, 1995, 176. 7. Elisabeth ML, Elies A, Marydele D. WWF Global Marine Turtle Strategy, 2009-2020, 2009. 8. Frazier J. Exploitation of marine turtles in the Indian Ocean. Human Ecol 1980; 8(4):329-370. 9. Jayaprakash A, Kasinathan AC, Ramamoorthy M. On the conservation and management of marine turtles. Marine Fisheries Information Service T&E Series 1993; (123):21-23. 10. Jones S, Bastian FA. Present status of turtle fishery in Gulf of Mannar and Palk Bay. In: Proceedings of the Symposium on Living resources of the seas around in India. CMFRI Special Publication, Mandapam Camp, 1973, 772-775. 11. Kar CS, Bhaskar S. Status of sea turtles in the Indian Ocean. In: The Biology and Conservation of Sea Turtles (Ed. Bjorndal

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