The Gulf of Mannar Marine National Park protected area comprises of the 21 small islands or islets, and adjacent coral reefs in the Gulf of Mannar region. Located at the southern tip of India, within the Indian Ocean, it is 1 to 10 kilometers away from the east coast of Tamilnadu. A 160 kilometer stretch between Dhanushkodi and Thoothukudi (Tuticorin) in South India, it forms the core region of the Gulf of Mannar Biosphere Reserve.
This Biosphere Reserve however, covers another 10 kilometer of buffer zone area around the National Park including the populated coastal regions. Public access inside the Park is in fact prohibited, which maintains a very high diversity of plants and animals within the marine, inter-tidal and set habitats along the shoreline. This 560 square kilometer Marine National Park is an extensive part of the 140 kilometer long and 25 kilometer wide Mannar Barrier Reef which includes groups of islets around Mandapam, Keelakarai, Vembar and Tuticorin regions.
The topography of the shoreline engulfs estuaries, mudflats, beaches and forests including marine components like coral reefs, seaweed communities, sea-grasses, salt marshes and mangroves. The flora of this region provides a very important feeding ground for Dugong, the vulnerable marine mammal, the endangered Green Turtles and the Olive Ridley Turtles sheltering within these localities. The other vertebrates of this Marine National Park include Indo-Pacific Bottle Noose Dolphin, the Finless Porpoise, Spinner Dolphin, Common Dolphin and over 510 species of fin fish species are found here, making it the most highly diverse fish habitat in India.
Dugong – The Vulnerable Marine Mammal: The Dugong is the only strictly marine herbivorous mammal who does not at all depend on fresh water for survival. Dugongs have a fusi-form body without any dorsal fins or hind limbs, but possess paddle-like fore-limbs used for maneuvering themselves. It is heavily dependent on sea grasses for subsistence, and hence restricted to coastal habitats where they grow in large numbers. These areas mostly consist of bays, mangrove channels and lee side area of large in shore islands where sea-grass is abundant. Dugongs have a sharply downturned snout adapted for grazing and uprooting benthic sea-grasses.