Sundarbans, the world’s largest mangrove ecosystem and also one of the UNESCO world heritage sites, is a mangrove area in the delta formed by the confluence of the Ganga, Brahmaputra and Meghna rivers in the Bay of Bengal. It is delimited in the north by the ‘Dampier-Hodges Line’, the Bay of Bengal is in the south, river Hooghly in the west and the rivers Harinbhanga, Raimangal and Ichemati in the East. At present, the total area of Sundarbans is 25,000 sq. km, out of which almost 40% of the area falls under India and the rest in Bangladesh. The Indian part of the Sundarbans comprises about 9630 sq. km, 4264 sq. km of which constitute a reserve forest.