Brief synthesisThe Sundarbans contain the world's largest mangrove forests and one of the most biologically productive of all natural ecosystems. About 66% of the entire mangrove forest area is estimated to occur in Bangladesh, with the remaining 34% in India. Criterion (ix): The Sundarbans is the largest area of mangrove forest in the world and the only one that is inhabited by the tiger. The Sundarbans support a wealth of animal species including the single largest population of tiger and a number of other threatened aquatic mammals such as the Irrawaddy and Ganges River dolphins. The Indian Forest Act, 1927 with its amendments, Forest Conservation Act 1980, Wildlife Protection Act, 1972 and Environment Protection Act 1986 are being effectively implemented, with rules and regulation regarding environmental pollution strictly enforced.