Conservation of Dugong dugon (sea cow) in Gulf of Mannar

Dugong dugon (dugongs) is probably one of the few living marine mammals surviving in pockets all around the Indian Ocean to the western part of the Pacific Ocean. These marine mammals are herbivores which spend their full life in the sea. They are the only extant species of the family Dugongidae super(1). All extant members of order Sirenia (including the dugong) are listed as vulnerable to extinction. All populations of dugong are also listed in Appendix 1 of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and in Appendix II of the Convention on Migratory Species (CMS). Dugongs are more closely related to elephants than marine mammals such as whales and dolphins, but their closet aquatic relatives are the manatees. The word 'dugong' means 'lady of the sea' super(3). Adults grow to about 2.5-3.5 m long, and weigh about 230--20 kg (ref. 4). They are generally solitary, travel in pairs, or associate, only in small groups (3-6 individuals) super(5). Their main food is sea grass (family Potamogetonaceae, Hydro-charitaceae, Cymodoceaceae); about 25-30 kg consumed per day. Female dugongs in season, attract the attention of several males, one or two of which will eventually mate with her. The young is born after a gestation period of 12--14 months. The mother will not calve again for periods of between 2.5 and 7 years. They have been known to live for more than 70 years in their natural habitat. Dugongs are generally found in warm waters around the coast with large numbers concentrated in wide and shallow protected bays located at a depth of around 10 m (33 ft) super(6). Populations of dugong exist in the waters of 37 countries and territories. Australia is home to the largest population; they also exist in the Gulf of Mannar and the Palk Strait between India and Sri Lanka, but are being seriously depleted. They are now endangered and subjected to a range of human threats in the Gulf of Mannar. Das and Dey super(6) suggest habitat loss as the main reason for population decline. This is attributed to the increasingly heavy boat traffic, toxic run-off from agricultural biocides, pollution from urban centres, oil spillage, bottom trawling and dredging and the commercial harvest of sea grasses super(7). Fishing activities around the Indian, Andaman and Nicobar, and Sri Lankan coasts, including gill netting and dynamite fishing also cause severe damage. In the Gulf of Kutch, dugong oil is valued as a preservative and conditi