CONSERVATION OF SEA TURTLES ALONG THE PUDUCHERRY COAST OF INDIA

SIVAKUMAR KUPPUSAMY1, PRACHI SACHCHIDANAND HATKAR1,#, R. SENTHIL KUMARAN2 & RAMANI SURESH KUMAR1

1Endangered Species Management Department, Wildlife Institute of India, Dehradun, India
2Indira Gandhi National Forest Academy, Dehradun, India
#pprachi62@gmail.com

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INTRODUCTION

Of the five species of sea turtle reported from Indian waters, Caretta caretta (loggerhead turtle), Chelonia mydas (green turtle), Dermochelys coriacea (leatherback turtle), Eretmochelys imbricata (hawksbill turtle), and Lepidochelys olivacea (olive ridley turtle) (Tikedar & Sharma, 1985; Rajagopalan et al., 1996) all except the leatherback have been reported offshore from the Union Territory of Puducherry (Kar & Bhaskar, 1982) on the east coast of India. Approximately 16km of the Puducherry coast is also utilised by nesting olive ridley (81.6%) and green turtles (16%) (Abraham, 1990; Bhupathy & Saravanan, 2006; Saravanan et al., 2013). Puducherry (11.882°-11.998° N, 79.750°-79.879° E), the regional capital and the second largest town of Puducherry Union Territory, is located along the Coromandel Coast (Figure 1).

Figure 1. Union Territory of Puducherry & Figure 2. Sea Turtle Nesting Beaches and Fishing Villages of Puducherry Union Territory

On its 36km coastline, Puducherry has a wide range of ecosystems, including estuaries, lagoons, mangroves, backwaters, and sandy beaches. The climate of Puducherry is semi-arid, with a mean annual temperature of 30°C and annual rainfall of about 1200mm (Smith, 2010; Lakshmi et al., 2012). Coconut and whistling pine (Casuarina sp.) plantations are observed along all beaches. Coastal plants such as morning glory (Ipomea pescaprae), Ravan’s mustache (Spinifex littoreus), Cyperus arenarius, southwest thorn (Prosopsis juliflora), and wild indigo (Teporosia purpurea) are common and act as sand binders (Smith, 2010; Muthulingam et al., 2013). During the northeast monsoon season, depressions and storms from the South Bay of Bengal cause heavy rain, thunderstorms, and gusty winds. Tidal waves flooding the low-lying coastal area accompany most of the storms.

Turtle Nesting in Puducherry

Sea turtle nesting usually begins in November and ends in April (although it may extend to June), with most turtles nesting from January to March. Turtles nest on dry, sandy beaches, ~20-40m above the high tide line, as observed in other parts of the world (Smith, 2010). The major turtle nesting beaches in the Puducherry region are at Narambai, Nallavadu, and Moorthikuppam villages, with 30-40 nests annually on each beach. Minor nesting beaches are found at Vanjiur village, near the Arasalar River in the Karaikal region (Figure 2). Minor nesting, with an average of 12-17 nests per beach annually, also occurs at Kanaga Chettikulam, Chinnakalapet, Periyakalapet Veerampattinam, Chinnaveerampattinam, Nallavadu, Pannithittu, Narambai, and Moorthykuppam, Vanjiur villages scattered along the Puducherry coast (Hatkar et al., 2016).

Threats to Nesting Sea Turtles and Their Eggs and Beaches in Puducherry

Twenty-three years ago, there were reports of as many as the 100 nests on Nallavadu beaches (Banugopan & Davidar, 1999). In 2021, only 21 nests were protected by the Forest Department, fishers’ ecological knowledge has also recognised a drastic decline in the turtles nesting on these beaches in the recent past (Jeyabaskaran & Kripa, 2018). All sea turtles in India are protected under the Wild Life (Protection) Act, 1972. However, during the nesting season, illegal take and sale of eggs, and exploitation of nesting turtles for meat, shell, flipper hide, oil, and fat have been significant threats. Until 2013, many villagers and fishers from Puducherry consumed turtle eggs and eggs were also sold in fish markets (Banugopan & Davidar, 1999; Sankar et al., 2016). Additional threats are predators like jackals and feral dogs that depredate turtle eggs in the area (Kuppusamy et al., 2016) and coastal erosion which has destroyed nesting beaches in Puducherry. Approximately 82% of the Coromandel coastline has experienced erosion due to the construction of ports and other development activities (Shanmugam et al., 2014; Salghuna & Bharathvaj, 2015). Aquaculture and tourism along nesting beaches has also contributed to a decline in nesting numbers (Hatkar et al., 2016).

Conservation of Nesting Sea Turtles and Their Eggs and Beaches in Puducherry

The Forest Department has initiated various turtle conservation actions, including preparing a turtle recovery plan for Puducherry, conservation of eggs during the peak nesting season (Figure 3), and involvement of villagers in turtle and nest protection. Forest Department officials faced a lot of difficulties while collecting eggs during the initial days. Miscreants would reach the beaches earlier than officials to take the turtle eggs. However, the Forest Department staff and youth volunteers reached out to fishers in coastal settlements such as Nallavadu, Pannithittu, Narambai, Moorthykuppam, and Pudukuppam about the importance of protecting turtles and their eggs. People who used to illegally take eggs and turtles have now been involved in protecting and monitoring turtles in Puducherry (Kishore, 2014).Figure 3. Collection of Eggs by Forest Department Personnel for Protection in a Hatchery. (Photo credit: T. Singaravelou.)

For many years, the Forest Department and local volunteers have patrolled nesting beaches. The Forest department has built temporary hatcheries along beaches between Nallavadu and Moorthykuppam. Two to three teams are formed every November to visit the villages for just a few hours. One team collects eggs along the coast from Gandhi Statue to Chinna Verrampattinam, another second team takes charge of the coast from the Boat House in Chunnambar to Pudukuppam, and the remaining team covers from Pudukuppam to Narambai. Once the eggs are collected from these places, they are taken to the temporary hatcheries to be protected under the supervision of the local volunteers.

Milestone events in the conservation of nesting sea turtles and their eggs in Puducherry are:

In 2000-01, the first formal survey of PuducherryChennai (Tamil Nadu) was conducted. Seven nests were recorded along 60km of coastline in January-February 2001 (Bhupathy & Saravanan, 2006).

In 2003-04, Mamallapuram-Puducherry beach (50km) was surveyed as part of the UNEP/CMS-IOSEA Project, A total of 540 nests were recorded, with peak nesting observed in the first fortnight of March (Bhupathy, 2007).

In 2004, 36 nests were recorded along 50km of Mamallapuram-Puducherry beach by Nethaji Snake Park Trust (NEST) volunteers (Saravanan et al., 2013).

In 2008, a rapid survey was undertaken by TREE Roots and Shoots, an NGO, and local fishers to record nests laid along beaches of the Puducherry coast. Interviews revealed that locals saw 10-15 turtles nesting on beaches before sea walls were erected (Vimalraj & Dharini, 2013).

In 2009, local NGOs began relocating the eggs at Veerampattinam to hatcheries on the same beach. Seven clutches, comprising 750 eggs, produced 700 hatchings. Hatchlings entangled in vegetation were rescued and released into the sea (Anonymous, 2009).

During 2011-12, sea turtle nesting surveys were carried out by Nethaji Snake Park Trust (NEST) volunteers. The volunteers walked a 10km stretch of coast daily from Kanagachetikulam to Puranakuppam in Pondicherry. Six nests were located between January and March 2012 and relocated to a safe place on the same beach to avoid depredation. These nests were monitored day and night by NEST volunteers. World Wildlife Fund surveyed from Mamallapuram to Pondicherry and found 44 olive ridley nests, with most laid between the second week of February and March 2012 (Saravanan et al., 2013).

In 2013-14, a total of 1,723 turtle eggs from six locations were relocated to temporary hatcheries in Nallavadu and Narambai (Forest Department, pers.comm.). The Forest Department involved villagers in finding nests and safeguarding the eggs.

During 2014-15 temporary hatcheries at 14 locations in Nallavadu and Narambai protected 1,800 eggs (Kishore, 2014; Prasad, 2016). Villagers helped the forest department to collect eggs (Prasad, 2016).

In 2015-16, A total of 888 eggs were collected between Kalapet and Kanniakoil coastal hamlets by forest officials and safely transferred to Narambai hatchery. The Forest Department and volunteers released 114 hatchlings into the sea at Narambai (Prasad, 2016).

In 2017-18, Puducherry Forest Department personnel and volunteers collected 11,500 eggs, the highest number in 15 years. Around 7,000 turtle hatchlings were released from hatcheries in Pudukuppam and Narambai under the supervision of local volunteers (Jeyabaskaran & Kripa, 2018).

During 2019-20, about 10,300 eggs were relocated to hatcheries in Narambai and Pudukuppam. The first batch of 240 hatchlings was released at Narambai in March 2020 in a joint initiative by the Forest Department and youth volunteers (Special Correspondent, 2020).

During 2020-21 the onset of the nesting season was delayed later than in previous seasons, possibly due to the influence of successive Cyclones Nivar and Burevi that swept through the eastern seaboard late 2020. Forest department officials and locals collected ~10,300
eggs for protection (Special Correspondent, 2020).

Even though such conservation initiatives can be productive, there is no systematic or structured management to protect the nesting beaches and hatcheries in Puducherry. Sea turtle nesting areas are declared Coastal Regulation Zone–I areas and considered ecologically sensitive. Maps have been prepared for the Union Territory of Puducherry by the Institute of Remote Sensing (IRS), Anna University, and approved by the Ministry of Environment Forest & Climate Change (Anonymous, 2019). As per the coastal regulation zone, 0.19km2 area is categorised as ecologically sensitive areas of turtle nesting ground (CRZ- IA) by the Coastal Zone Management Plan. In such areas, no development or new construction can occur.

Threats to In-water Sea Turtles and Their Habitats

The number of sea turtles inhabiting waters off the Pondicherry coast is uncertain. Light pollution has been disrupting the movements of adult turtles and disorienting hatchlings. The bycatch of sea turtles in fisheries is a serious and growing threat along this coastline (Sankar et al., 2016) and needs to be quantified. Drowning in trawl nets along the Pondicherry coast is the primary cause of the decline of sea turtle populations (Sankar et al., 2014). Once sea turtles have been entrapped in the trawl net, they can be dragged over for 1-3 hours; as a result, turtles often receive injuries to their head and elsewhere (Donnelly, 2008). Sometimes, fishers cut off the flippers to remove turtles from the fishing net. Analysis of ghost nets recovered from the Puducherry coast from August to September 2013 showed they were constructed of monofilament and made of high-density polyethylene (Stelfox et al., 2015).

In 1998-99, preliminary surveys carried out from December 1998 to April 1999 found 54 carcasses of turtles on Puducherry beaches. Fishers admitted that trawler operations were responsible (Banugopan & Davidar, 1999).

In 2003-04, 139 turtle carcasses were found within a 3km stretch of coast from Mamallapuram to Pondicherry (Bhupathy et al., 2006).

From 2003-05, carcasses of 135 olive ridley and five green sea turtles were found on the Puducherry beaches (Bhupathy et al., 2007).

From December 2011 to March 2012, 143 carcasses of olive ridley turtles were reported in the Karaikal region (Vinoth & Sandilyan, pers. comm.). Also, in 2011-12, 139 olive ridley turtle carcasses were found along the Mamallapuram to Pondicherry coast (Saravanan et al., 2013).

In December 2013, ~100 stranded dead turtles along the Nagapattinam coast were reported by Tree Foundation (Jha, 2014).

A detailed study of the nesting and carcasses of turtles was not available in Puducherry till 2013 (Pande, 2014). In 2013-14, 47 turtles were found dead around the Pudducherry coast (Table 1). Many were found near the Nallavadu estuary (Forest Department, pers.comm.).

From 2013-15, the Forest Department observed the highest mortality of sea turtles in the month of January, when fishing peaked. Before and during January each year, turtles aggregate in shallow water s near the beach for breeding. These same waters are also substantial gillnet fishing grounds (Bhupathy et al., 2006).

In 2014-15, another 111 dead turtles were found along the Puducherry coast (Table 2), most from Nallavadu, Narambai, Veerampattinam, and Pannithittu. The carcasses found on the beach of Narambai had carapace damage from being hit by boat propellers. Bycatch rates of sea turtles have not been studied in this area yet.

Many of the carcasses found in the studies above were decomposed, and post-mortem examination could not conclusively determine the cause of death.

Conservation of In-water Sea Turtles and Their Habitats

Most turtle mortality along the Puducherry coast, excluding areas off the coast of Mahe, Karaikal, and Yanam, occurs from December to April (Jeyabaskaran & Kripa, 2018). Srivastava & Ahuja (2002) suggested that TEDs should be implemented along the coast (excluding the named areas) from December to April. The Fisheries Department has issued directions for fishers to cut their nets to free trapped turtles, and the Forest Department and Fisheries Department are exploring the possibility of compensating the fishers to release entangled sea turtles. Fishers having proof of a sea turtle entangled in their net and released alive can claim compensation (Jeyabaskaran & Kripa, 2018).

Local NGOs such as Temple Reef Foundation have been conducting ghost net and beach clean-up activities (Jagannathan, pers.comm.). National Institute of Ocean Technology designed and implemented the pilot project ‘Restoration of Puducherry Beach’ in March 2017. Construction of northern wedge reef was completed in August 2018. Sand nourishment has been carried out in parallel, and is to be continued. Construction of the southern reef is yet to commence (Anonymous, 2017).

One stranded, female olive ridley turtle was rescued from Murthikuppam beach in December 2018 and was released successfully after treatment by a local veterinarian (Staff
Reporter, 2018). Currently, there are no facilities or rehabilitation centres to treat stranded or bycatch turtles.

RECOMMENDATIONS

The number of sea turtles inhabiting waters off the Puducherry coast is uncertain. There is no information about the spatial occupancy and movement pattern of sporadic sea turtle populations nesting on the beaches of this coast, which is crucial for spatial planning for biodiversity conservation and rational planning of marine ecosystems, including sea turtles are under threat due to developmental activities.

1. Human activities on the beach should be highly regulated during the breeding season to avoid illegal take. The turtle nesting sites of Puducherry need to be identified and mapped and declared as ecologically sensitive areas or ‘Community or Conservation Reserves’. Such reserves should be managed with the active participation of local communities for the long-term conservation of sea turtles in Puducherry.

2. Hatchery management practices need to be reviewed and regulated. Hatching success needs to be evaluated, and accurate records must be maintained.

3. Regular beach cleaning activities should be conducted through government and private organizations to increase public awareness; proper collection and disposal of marine debris to maintain nesting beaches and nearby coastal areas should be practiced. Incentive schemes should be given to locals and fishers to protect the sea turtles.

4. The government of India is developing a policy to deal with marine species that frequently get stranded on shores. The policy will help identify the hotspots where marine stranding is taking place. Once that is completed, a Rapid Response Team and veterinary and medical facilities will be deployed to treat these species and put them back in the water. Morphometric records of the strandings need to be maintained since the morphological analysis of characteristics can impart information about the life of the turtles.

5. Wildlife Institute of India has advised the Puducherry Government to initiate the ‘Marine
Turtle Scholarship’ to school-going children of poor fishermen communities to strengthen the involvement of fishermen communities in Marine Turtle Conservation. The children would become ‘Turtle Ambassadors’ and promote conservation.

6. Hotspots of fisheries interactions with sea turtles need to be identified. Turtle excluder devices should be strictly implemented, and the ban on nearshore mechanised fishing and fishing in high-use areas or migratory or foraging grounds should be strictly enforced to reduce bycatch rates and mortality of sea turtles.

7. The Wildlife Institute of India formed an action plan for conservation to address these issues and regulate the conservation actions for the onshore and offshore natural and anthropogenic threats to the sea turtles. However, when done correctly and in accordance
with all laws, nourishment may create suitable habitats for rare or threatened organisms like sea turtles (Speybroeck et al., 2006). Beach nourishment is generally only beneficial to sea turtles in areas with less degraded nesting habitats. Department of Science, Technology and Environment is proposing to prepare a geospatial database on the coastal resources of Puducherry under the Integrated Coastal Zone Management Project, which will help the planners in identifying and addressing the key issues.

ACKNOWLEDGMENTS

The authors would like to thank the Forest Department of Puducherry for supporting and providing exhaustive and vital information for this study. We also thank Mr. Prem Jyothi, Dr. Priyamvada Bagaria, Dr. Ramesh Chinnasamy, and Dr. D. Adhavan for their support during our study. We are very grateful to the Director and Dean of the Wildlife Institute of India, Dehradun, for their constant encouragement and support. We are also thankful for the IOTN editor’s valuable suggestions for improving the manuscript.

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