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The Indian Ocean Turtle Newsletter was initiated to provide a forum for exchange of information on sea turtle biology and conservation, management and education and awareness activities in the Indian subcontinent, Indian Ocean region, and South/Southeast Asia. The newsletter also intends to cover related aspects such as coastal zone management, fisheries and marine biology. The newsletter is distributed free of cost to a network of government and non-government organisations and individuals in the region. All articles are also freely available in PDF and HTML formats on the website. Readers can submit names and addresses of individuals, NGOs, research institutions, schools and colleges, etc for inclusion in the mailing list. SUBMISSION OF MANUSCRIPTS IOTN articles are peer reviewed by a member of the editorial board and a reviewer. In addition to invited and submitted articles, IOTN also publishes notes, letters and announcements. We also welcome casual notes, anecdotal accounts and snippets of information. Manuscripts should be submitted by email to: [email protected] If electronic submission is not possible, mail hard copies to: Kartik Shanker Centre for Ecological Sciences Indian Institute of Science Bangalore 560012. India. Manuscripts should be submitted in MS Word or saved as text or rich text format. Figures should not be embedded in the text; they may be stored in EXCEL, JPG, TIF or BMP formats. High resolution figures may be requested after acceptance of the article. In the text, citations should appear as: (Vijaya, 1982), (Silas et al., 1985), (Kar & Bhaskar, 1982). References should be arranged chronologically, and multiple references may be separated by a semi colon. Please refer to IOTN issues or to the Guide to Authors on the website for formatting and style. Authors should provide complete contact information including an email address, phone and fax numbers. Reference styles in list: Vijaya, J. 1982. Turtle slaughter in India. Marine Turtle Newsletter 23: 2. Silas, E.G., M. Rajagopalan, A.B. Fernando & S. S. Dan. 1985. Marine turtle conservation & management: A survey of the situation in Orissa 1981/82 & 1982/83. Marine Fisheries Information Service Technical & Extension Service 50: 13-23. Pandav, B. 2000. Conservation & management of olive ridley sea turtles on the Orissa coast. PhD thesis. Utkal University, Bhubaneswar, India. Kar, C.S. & S. Bhaskar. 1982. The status of sea turtles in the Eastern Indian Ocean. In: The Biology and Conservation of Sea Turtles (ed. K. Bjorndal), pp. 365-372. Smithsonian Institution Press, Washington D.C., USA. This newsletter is produced with support from: IOTN ONLINE IS AVAILABLE AT http://www.seaturtle.org/iotn Indian Ocean Turtle Newsletter No. 5 Monitoring of marine turtles along the Kerala and Tamil Nadu coasts S. Bhupathy Sálim Ali Centre for Ornithology and Natural History Anaikatti (PO), Coimbatore, Tamil Nadu 641108, India. Email: [email protected] Introduction Methodology Among the five species of sea turtles distributed in Study area the Indian region, four of them, the olive ridley (Lepidochelys olivacea), green turtle (Chelonia The all-India coordinated UNDP–GOI–WII sea mydas), leatherback (Dermochelys coriacea) and turtle project (2000–2001) suggested that the hawksbill (Eretmochelys imbricata) nest on Indian Nagapattinam and Chennai coasts in Tamil Nadu coasts (Kar & Bhaskar, 1982). All these species are and the beaches of North Kerala are important distributed in Tamil Nadu and in the coastal waters marine turtle nesting areas (Bhupathy & of Kerala. The Wildlife Institute of India (WII) Saravanan, 2006b). We monitored turtle nesting recently implemented a UNDP–Government of and mortality along the south Chennai (12o31’– India sea turtle conservation project. This project 12o8’N and 80°10’–79°56’E, Fig. 1) and (2000–01) evaluated the status of marine turtles Nagapattinam coasts (11o51’–11o30’N and 79°51’– and their nesting habitats in all maritime states of 79°46’E, Fig. 2) which are part of the Palar and India, which included an assessment of threats to Cauveri deltas respectively. The North Kerala turtles. Data on important nesting beaches were coast (approx. Kozhikode–Kannur; 11o41’– generated, which form the benchmark for 12o38’N and 74°55’–75°38’E, Fig. 3) has many monitoring (Shanker & Choudhury, 2006). west flowing rivers and remnants of mangrove Information on the status of marine turtles along vegetation at the river mouth. The west and east the Tamil Nadu coast was generated as a part of coasts receive major rainfall from the Southwest this project (Bhupathy & Saravanan, 2002, 2006a; (May–July) and Northeast (October–November) Bhupathy & Karunakaran, 2003). Among many monsoons respectively. aspects, monitoring the population trend of a species is critical for the preparation and Field methods implementation of conservation programmes. In this context, the Madras Crocodile Bank Trust Each study sector was divided into 10–km units (MCBT) initiated a countrywide programme for and surveyed each fortnight (during 0600–0830 monitoring marine turtles including the islands. As hours) for recording nesting and mortality of a part of this programme, the Sálim Ali Centre for turtles (Table 1). Data on nesting intensity was Ornithology and Natural History (SACON), based on tracks found on the beach. As surveys Coimbatore undertook monitoring of sea turtles were done at fortnightly intervals, tracks found along the Kerala and Tamil Nadu coasts during during each survey were considered as new. Nest 2003–05. The objective of this project was to predation by animals or exploitation by locals was assess the conservation status of different species based on tracks and signs found near exploited of marine turtles, and to network with and provide nests. The number of carcasses found on the shore training to government officers and non- was counted as an index of turtle mortality. government organisations (NGOs) in both states to Carcasses of turtles were marked with paint to enhance conservation actions. In this paper, we avoid repeat count. Researchers appointed by the report the major findings of the sea turtle project surveyed the Mamallapuram–Pondicherry monitoring programme along the Kerala and Tamil (50 km) and Nagapattinam (30 km) beaches each Nadu coasts during November to April 2003–04 fortnight by foot. The Chennai (6 km) and North and 2004–05. Kerala (20 km) beaches were monitored by local January, 2007 1 Indian Ocean Turtle Newsletter No. 5 NGOs on a daily basis. Along the North Kerala study. Total nesting during the season was coast, the availability of sandy areas for turtle estimated as: nesting was assessed during February–March 2003. We also interviewed local persons to obtain N = n × d × t, information on turtle nesting and mortality. where N – Estimated nesting, n – average nesting during sampling, Nesting intensity for the locality studied was d – number of 10 km sectors, and calculated based on average nesting during this t – duration (90 days – January to March). Table 1: Sea turtle monitoring schedules along the Kerala and Tamil Nadu coasts during 2003 - 05 Beach Sector Distance (km) Duration Monitored by Kerala Kozhikode 6 September–December 2003 Theeram Kasarakod 10 September–December 2003 Naythal Tamil Nadu Chennai 6 January–April 2004 SSTCN January–April 2005 Mamallapuram- 50 January–April 2004 MCBT–CMS Pondicherry Project Nagapattinam 30 January–April 2004 MCBT–CMS December 2004–May 2005 Project Turtle Monitoring hatcheries are used for nature education and public awareness programmes. Nesting The Mamallapuram–Pondicherry beach (50 km) Sandy beaches suitable for sea turtle nesting were was surveyed for only one year (2003–04). In all, found on the North Kerala (i.e. Kannur and 36 olive ridley nests were recorded during the Kasarkod) coast. A survey conducted for fortnightly sampling from January–March 2004. documenting nesting and mortality along the 60 Peak nesting was observed in the first fortnight of km coast during February–March 2003 yielded no March. Estimated nesting density along this area nests. Interviews with fishermen revealed that was about 11 nests per km during January–April turtles nest along the west coast largely during 2004 (Table 2). September–November with the peak during October. Data collected by NGOs working in this The Chennai beach has been monitored (on a daily area, namely Theeram and Naythal supported this. basis) by the Students’ Sea Turtle Conservation According to them, on an average, about three Network (SSTCN) since 1988 and was continued nests were found per kilometer in the area. These during this study as well. A total of 50 nests (8.3 NGOs, in collaboration with the Kerala Forest per km) were recorded during January–April 2004. Department and local communities, especially the During 2005, they recorded 62 nests (10.3 per km; fisherman, collect turtle eggs and maintain SSTCN data). Average nesting intensity for 16 hatcheries in Kolavipalam, Kozhikode (Theeram) years was 9.4 nests per km (Shanker, 2003). A and near Kasargod (Naythal). The hatchlings are hatchery is being maintained by the SSTCN on an released into the sea. Apart from collecting annual basis. biological information and protecting nests, these January, 2007 2 Indian Ocean Turtle Newsletter No. 5 Table 2: Nesting of ridleys along the Turtle nesting along the east coast of Tamil Nadu Mamallapuram–Pondicherry coast (50 km), Tamil (Chennai and Nagapattinam) occurred during Nadu during January–March 2004 January to March, whereas it was between September and December along the North Kerala Fortnight Number of Average coasts. In other words, turtles nested subsequent to nests nesting/ the major monsoon season of the area, namely the day/10km northeast and southwest monsoons. Peak nesting January I 3 0.6 along the east and west coasts were during January II 6 1.2 February and October respectively. The intensity February I 7 1.4 of the sea turtle nesting on the Kerala and Tamil February II 7 1.4 Nadu coasts is sporadic, and its density varied March I 13 2.6 from 3 to 15 nests per km.