Chelonia Mydas
Scientific Name:-
Chelonia MydasCommon Name:-
Green Turtle
Malayalam Name:-
Pacha kadalama
Category:-
Sea turtles
Status:-
: Endangered A2bd ver 3.1 (IUCN Redlist); Appendix I of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora); and Appendices I and II of the Convention on Migratory Species (CMS).
Indian Wildlife (Protection) Act: Schedule I
Description:-
The Green Turtle has an olive green, nearly circular or heart-shaped carapace (upper shell) up to 1.5 m in length. The carapace is usually variegated with brown, reddish-brown and black on the top and whitish or cream underneath. Maturing specimens bear radiate patterns on the carapace. Carapace is composed of five central scutes flanked by four pairs of lateral scutes or costal shields (shell plates located on either side of the mid-line) between the centre and outer margin of the upper shell. Green turtle’s snout is very short and its beak is unhooked (help to distinguish it from the closely related hawksbill turtle. Upper jaw possesses a denticulated edge, while its lower jaw has stronger, serrated, more defined denticulation. The dorsal surface of the turtle's head has a single pair of prefrontal scales. The green turtle has four pairs of inframarginal scutes covering the area between the turtle's plastron and its shell. In adults the flippers have only a single claw (compared to two in hawksbill turtle); young ones may have a second claw.
The name green turtle might have come from the greenish colour of the turtles' fat, which is only found in a layer between their inner organs and their shell. The average weight of mature individuals is 68–190 kg and the average carapace length is 78–112 cm.
They feed on sea grasses and algae, although they will occasionally eat other items including mangrove, jellyfish and sponges. Female Green Turtles vary in their age at maturity depending on the different foraging grounds they occupy. Females may reach sexual maturity at between 25 to 50 years of age, and they may live up to 80 years in the wild. Breeding male and females move from their feeding grounds to areas near nesting beaches for mating. The female stores sperm, which may last through several nestings in one year. Females crawl out on beaches, dig nests and lay eggs during the night. Nesting occurs every 3-6 years. 100-200 eggs are laid in burrows dug out by the female on isolated sandy beaches, and covered with sand to protect them from the sun. The young hatch after 6-8 weeks and make a journey towards the sea. Green Turtles can migrate more than 2600 km between their feeding and nesting grounds.
Threats:-
Exploitation for egg and meat. Incidental catches in fishing nets such as trawl net and gill net. Degradation of both nesting beach habitat and marine habitats also play a role in the decline of their population in Kerala coast.
Remark:-
Green turtles exhibit particularly slow growth rates, and age to maturity for the species appears to be the longest of any sea turtle. Therefore conservation should be prioritised. They are sighted occasionally in Kerala.
Habitat:-
They are found in different habitats depending on their life stage. They lay eggs on beaches. Mature turtles spend most of their time in shallow, coastal waters with lush seagrass beds. Adults frequent inshore bays, lagoons and shoals with lush seagrass meadows. Entire generations often migrate between one pair of feeding and nesting areas.
Synonyms:-
Testudo mydas Linnaeus, 1758
References:-
Bhaskar, S. 1981. Sea turtle survey of the Kerala coast. Report to the WWF-India, 6pp.
Bhupathy, S. 2007. Monitoring of marine turtles along the Kerala and Tamil Nadu coasts. Indian Ocean Turtle Newsletter 5: 1–9.
Das, I. 1995. Turtles and tortoises of India. Oxford University Press, Delhi.
Deepak Apte (2012). Field Guide to the Marine Life of India. Deepak Apte, Thane, Maharashtra, 502pp.
Dileepkumar, N. and Jayakumar, C. 2002. Field study and networking for turtle conservation in Kerala – A GOI-UNDP sea turtle project report.
Dileepkumar, N. & C. Jayakumar. 2006. Sea turtles of Kerala. In: In: Marine turtles of the Indian subcontinent (K. Shanker, B.C. Choudhury, Eds). Pp. 137–140. Universities Press (India) Private Ltd.
Krishna Pillai, S. 2004. Accidental catch of green turtle Chelonia mydas in shore-seine at Kovalam near Vizhinjam, south Kerala. Fishing Chimes 24(3): 57.
Palot, M.J. and Radhakrishnan, C. 2004. Status and distribution of turtle fauna (Testudines: Reptilia) in the Malabar part of Kerala, India. Records of Zoological Survey of India ,102(Part 1-2): 27–39.
Sea turtles of India. 2011. A comprehensive field guide to research, monitoring and conservation (Compilers. S. Shenoy, T. Berlie and K. Shanker). Dakshin Foundation, Bangalore and Madras Crocodile Bank Trust, Mamallapuram, India. 148pp.
Seminoff, J.A. (Southwest Fisheries Science Center, U.S.) 2004. Chelonia mydas. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. <www.iucnredlist.org> Downloaded on 01 August 2013
Shanker, K. 2003. (Ed.) Manuals on sea turtle conservation. A GOI UNDP Sea Turtle Project. Centre for Herpetology/Madras Crocodile Bank Trust, Tamil Nadu, India.
Shanker, K. and B.C. Choudhury. 2006. Marine Turtles of the Indian Subcontinent. Universities Press, Hyderabad.
Smith, M. A. 1941. Fauna of British India. Reptilia and Batrachia.
Murthy, T.S.N. & A.G.K. Menon. 1976. The turtle resources of India. Seafd. Expt. J. 8(1):1-8.