Description : Spotted deer in Sundarban. It is the largest littoral mangrove forest in the world. The Sundarbans cover an area of 38,500 sq km, of which about one-third is covered in water. Since 1966 the Sundarbans have been a wildlife sanctuary, and it is estimated that there are now approximately 400 Royal Bengal tigers and about 30,000 spotted deer in the area. Sundarban, Khulna, Bangladesh.