The Sundarbans mangrove forest, one of the largest such forests in the world, lies on the delta of the Ganges, Brahmaputra and Meghna rivers on the Bay of Bengal. It is a UNESCO World Heritage Site inscribed in 1987. The area is known for the famous Royal Bengal Tiger, its wide range of fauna including 260 bird species, and other threatened species such as the estuarine crocodile and the Indian python. The Sundarbans provides sustainable livelihoods for millions of people in the vicinity and acts as a shelter belt to protect the people from storms, cyclones, tidal surges, sea water seepage and intrusion. The area provides livelihood in certain seasons for large numbers of people living in small villages, working variously as wood-cutters, fisherman, honey gatherers, leaves and grass gatherers.