Ganges Delta trees are found in these areas. The delta region has mangrove trees. It is estimated that 30,000 chital ("Axis axis") are in the Sundarbans part of the delta. Birds found in the delta include kingfishers, eagles, woodpeckers, the shalik ("Acridotheres tristis"), the swamp francolin ("Francolinus gularis"), and the doel ("Copsychus saularis"). Two species of dolphin can be found in the delta: the Irrawaddy dolphin ("Orcaella brevirostris") and the Ganges river dolphin ("Platanista gangetica gangetica"). The Irrawaddy dolphin is an oceanic dolphin which enters the delta from the Bay of Bengal. The Ganges river dolphin is a true river dolphin, but
Harike Wetland (6 & 32 taxa), Crustaceans (27 taxa), Annelids (7 taxa), Nematodes (7 & 4 taxa), Rotifers (59 & 13 taxa), and Protozoans (5 & 21 taxa). The Indus dolphin (Platanista gangetica minor) supposed to have become extinct in India after 1930, but largely found in the Indus river system in Pakistan, was recently sighted in the Beas River in Harike wetland area. This aquatic mammal classified as an endangered species in the Red Data Book of the International Union for the Conservation of Nature and Natural Resources is considered a significant find. The dolphins were discovered by Basanta Rajkumar, IFS