For centuries Nepal is renowned as one of the best areas for wildlife viewing in Asia. The diverse flora and fauna of the low land of Terai national parks attracts wildlife enthusiasts from all over the world. Equally interesting for ornithologists, the following three national parks prize the bird lovers with several hundred species of native as well as migratory birds, some from as far away as upper Mongolia, Siberia and even Spain. Royal Chitwan National Park (932 sq. km) is considered to be one of the richest wildlife areas in Asia and boasts the largest remaining areas of tall & bounteous grassland habitat. The park lies between Siwalik (Churia) and Mahabharat range and is drained by the Narayani and Rapti rivers. In 1964 a sanctuary was declared by moving Tharu peoples who developed a resistance to malaria. In 1973 the national park was established with the protection of Royal Nepalese Army. Over 50 species of mammals and 450 species of birds are found in the park. The Royal Bardia National Park, located in the remote and sparsely settled far west Terai is an untouched and is one of the best to see tigers and leopards in the forests. The Karnali river forms its western boundary and Siwalik (Churia) the northern boundary. In 1988 the national park was established by adding the eastern extension to Royal Karnali Wildlife Reserve to its present size (968 sq. km). The phantas, the short grassland meadows on the forest edge are the characteristic of Bardia. Koshi Tappu Wildlife Reserve in the eastern Terai lies on the floodplain of the Sapta Kosi river. The reserve is bounded on the south by the barrage and on the east & west by river banks. The little reserve (175 sq. km) is a haven for waterfowl during winter and more than 20 different ducks and the rare swamp partridge. As many as 280 species of birds have been recorded here. It harbors the only remaining wild buffaloes.