Dudhwa Tiger Reserve is a typical representative of the terai eco system. Indian portion of terai arc landscape, stretching from Yamuna river in the west to Valmiki Tiger Reserve, Bihar in the east, spreads across five states along the Shivaliks and Gangetic plains.
This unique landscape consist of two distinct zones i.e. (i) Bhabar, characterized by a hilly terrain with coarse alluvium and boulders, and Sal mixed and miscellaneous vegetation communities and (ii) terai, characterized by fine alluvium and clay rich swamps dominated by a mosaic of tall grassland and Sal forest. The terai. in particular, is listed among the globally important 200 eco-regions for its unique large mammal assemblage. Over the decades as a result of conquest of malaria, establishment of numerous settlements and consequent increase in human population in the post-independence era, this landscape has become highly fragmented and degraded. This has led to the local extinction of species such as one-horned rhinoceros (Rhinoceros unicornis) and northern swamp deer (Cervus duvauceli duvauceli), though measures for the revival of their population has started lately.
In this scenario Dudhwa Tiger Reserve comprising of three Protected Areas i.e. Dudhwa National Park, Kishanpur Wildlife Sanctuary and Katerniaghat Wildlife Sanctuary, stands out as the primary Protected Area Complex of the terai with one of its components having the status of a National Park.
Dudhwa National Park is the only National Park and Tiger Reserve representative of Terai-bhabar Biogeographic subdivision of the Upper Gangetic Plains (7a) Biogeographic province. The vegetation of the area is of North Indian Moist Deciduous type. It has some of the finest sal forests in the country. Current documentation indicates the presence of vast variety of plants and plant communities. Several of these are of conservation significance.
The Dudhwa Tiger Reserve is the only place in the country to hold a potentially viable population of the nominate sub-species of the northern swamp deer (Cervus duvauceli duvauceli). Of the seven species of deer found in the country, five occurs in the Reserve. It is also home to a sizeable tiger population. Some critically endangered species such as the Bengal Florican (Hubaropsis bengalensis) and Hispid Hare (Caprolagus hispidus) find a home here. Dudhwa is also the place where the Great Indian One–Horned Rhinoceros has been successfully reintroduced in the year 1984. Thirteen species of mammals, nine species of birds, and eleven species of reptiles and amphibians found here are considered to be endangered and are listed in Schedule–1 of the Wild life (Protection) Act, 1927.
The area of the Park and Sanctuary also plays a vital role in the maintenance of the water and climatic regime of the region, which in turn is vital for agriculture and other allied activities. It also performs a host of other functions which, though not fully understood, are nevertheless critical for the continued wellbeing and existence of humanity.
Dudhwa National Park is located on the Indo-Nepal border in the palia and Nighasen Tehsil of district Lakhimpur-Kheri and lies between 28° 18´N and 28° 42´N latitudes and 80° 28´E and 80° 57´E longitudes. The total area of the Park is 49029.19 ha. Reserved forest area of 12401.39 ha serves as its northern buffer and an area of 6602.32 ha serves as its southern buffer. The areas, which constitute Dudhwa National Park and its buffer, were once part of the North Kheri Forest Division.
The State Government declared its intent to create a National Park by a notification in the official gazette in October 1975. Upon completion of settlement proceedings, the Park was finally notified through the Govt. of U.P. Forest Department Notification number 6991/14-3-1/74, dated 21.1.77 and established on February 1, 1977.
The Kishanpur Sanctuary straddles Gola Tehsil of Lakhimpur district and the Powayan Tehsil of Shahjehanpur district. It lies between the latitudes 28° 14´ to 28° 30´N and longitudes 80° 18´ to 80° 30´E and covers an area of 20341.00 ha. The area of the Sanctuary was once part of the South Kheri Forest Division. It was established on 1.1.1973 in continuation of orders issued vide G.O.U.P. notification no. 111/14-3-31/1972 dated 7.10.1972.
The Katerniaghat WLS is located in the Nanpara Tehsil of district Bahraich. The Indo-Nepal border constitutes the northern boundary of the WLS. The entire area, totaling 40009.35 ha is situated between 28006’ N and 28024’ N latitudes and 81002’ E and 80019’ E longitudes. Consequent upon Govt. of UP notification no. 388/14-3-32/1976 dated May 31, 1976, these forests came to be constituted as a Wildlife Sanctuary. The Sanctuary, together with the adjoining 15002.75 ha. of Reserve Forests, which serve as buffer, constitutes one ecological and administrative unit.