With the exception of the Chattogram Hill Tracts District, portions of the Madhupur Tract, and the Sundarbans (a great tidal mangrove swamp in the southwestern corner of the country), few extensive forests remain in Bangladesh, the forested and wooded area amounting to about one-eighth of the total area. Broadleaf evergreen species characterize the hilly regions, and deciduous trees, such as acacia and banyan, are common in the drier plains areas. Commercially valuable trees in Bangladesh include sundari (hence the name Sundarbans), gewa, sal (mainly growing in the Madhupur Tract), and garyan (in the Chattogram Hill Tracts District). Village groves abound in fruit trees (mango and jackfruit, for instance) and date and areca (betel) palms. The country also has many varieties of bamboo.
Bangladesh is rich in fauna, including 109 indigenous species of mammals, 684 types of birds, 119 kinds of reptiles, 19 different amphibians, and 200 varieties of marine and freshwater fish. The rhesus monkey is common, and gibbons and lemurs are also found. The Sundarbans area is one of the principal remaining domains of the Bengal tiger, and herds of elephants and many leopards inhabit the Chattogram Hill Tracts District. Other animals living in Bangladesh include mongoose, jackal, Bengal fox, wild boar, parakeet, kingfisher, vulture, and swamp crocodile.