The beautiful tropical island arc of Nicobar is part of the union territory of Andaman and Nicobar Islands, India. These islands are situated in the south–east of the Bay of Bengal, around1200 km east of main land India between 6° – 10° N latitude and 92° – 94° E longitude, and separated from the Andaman group by 10° channel. A variety of landforms can be seen along the coast and isolated islands laden with lush green tropical vegetation and beaches dotted with coconut trees. The islands of Nicobar are inhabited by two aboriginal tribes of Indo–Mongoloid origin. One of them is Nicobarese who live in twelve inhabited islands with a major concentration in Car Nicobar. The other tribe is Shompen, whose members live in the interior areas of Great Nicobar. The lush evergreen forest, undulating terrain, tall coconut trees behind the scintillating sandy beaches, and coral belt surrounding the island with green water gradually merging with deep blue water characterize these islands from distance. The Nicobar archipelago was not discovered all of sudden rather it was also known to the ancient mariners sailing to Southeast Asia from India, Middle East and Europe. A careful insight into the maritime history of the Indian Ocean would reveal several references to these islands by different mariners in different names. It may be a passerby citation or sometimes detailed description of its location and resources as could be seen from the Chola dynasty inscriptions of South India and Chinese travelers′ remarks. Between the 11th and 12th centuries A.D. some of these islands came under the dominating influence of maritime power of Southern India and as history would repeat itself it again became a part of the mainland India about nine hundred years later (Syamchaudhuri, 1977). Geologically the Nicobar Islands are part of a great island arc created by the collision of the Indo–Australian Plate with Eurasia. The collision lifted the Himalayas and most of the Indonesian islands, and created a long arc of highlands and islands, which includes the Arakan Yoma range of Burma, the Andaman and Nicobar Islands, and the islands off the west coast of Sumatra, including the Banyak Islands and Mentawai Islands. Nicobar Islands are formed on a coralline base with marine sediments. Except for Great Nicobar Island, all other islands in the Nicobar group are relatively smaller in size surrounded by reef.