| Terai-Duar savanna and grasslands | |
|---|---|
 Indian rhinoceros inChitwan National Park, Nepal | |
 | |
| Ecology | |
| Realm | Indomalayan |
| Biome | tropical and subtropical grasslands, savannas, and shrublands |
| Borders | |
| Bird species | 366[1] |
| Mammal species | 115[1] |
| Geography | |
| Area | 34,600 km2 (13,400 mi2) |
| Countries | |
| Coordinates | 27°30′N84°20′E / 27.50°N 84.33°E /27.50; 84.33 |
| Conservation | |
| Habitat loss | 90.62%[1] |
| Protected | 8.91%[1] |
TheTerai–Duar savanna and grasslands is a narrow lowlandecoregion at the base of theHimalayas, about 25 km (16 mi) wide, and a continuation of theIndo-Gangetic Plain inIndia,Nepal andBhutan. It is colloquially calledTerai in theGanges Basin east to Nepal, thenDooars inWest Bengal, Bhutan andAssam east to theBrahmaputra River. It harbours the world's tallestgrasslands, which are the most threatened and rare worldwide.[2]
Thistropical and subtropical grasslands, savannas, and shrublandsbiome stretches from westernBhutan to southernNepal'sTerai, westward toBanke, covering theDang and Deukhuri Valleys along theRapti River toIndia'sBhabar andDoon Valley. Each end crosses the border into India's states ofUttarakhand,Uttar Pradesh andBihar.[2] The eastern and central areas are wetter than the western end.
In Nepal, the wetlands ofKoshi Tappu Wildlife Reserve,Beeshazar Tal in the bufferzone ofChitwan National Park,Jagdishpur Reservoir andGhodaghodi Tal are designatedRamsar sites.[3]Shuklaphanta National Park is Nepal's largest patch of continuous grassland.[4]
The Terai–Duar savanna and grasslands are a mosaic of tall riverside grasslands, savannas andevergreen and deciduous forests, depending onsoil quality and the amount of rain each area receives. The grasslands of theTerai in Nepal are among the tallest in the world, and are maintained by silt deposited by the yearlymonsoon floods. Important grasses includebaruwa (Tripidium bengalense) andkans grass (Saccharum spontaneum), which quickly establishes itself after the retreat of the monsoon waters. In the hillier areas the dominant tree issal (Shorea robusta), which can grow to a height of 45 m (148 ft). The belt also contains riverside tropicaldeciduous forest comprisingMallotus philippensis,jamun,cotton tree,Mallotus nudiflorus, andGaruga pinnata.[2]
The ecoregion is habitat for a huge number ofmammalian andbird species.[1] Notable are the large numbers of the endangeredgreater one-horned rhinoceros andBengal tigers as well asAsian elephants,sloth bears,Indian leopards.
In Nepal'sChitwan National Park, more than 400 rhinos were sighted in 2008, and 125 adult tigers were recorded during a survey conducted from December 2009 to March 2010, which covered an area of 1,261 km2 (487 sq mi).[5][6] Nepal'sBardia National Park andShuklaphanta National Park, and India'sValmiki andDudhwa National Parks are home to nearly 100 tigers. Chitwan along with the adjoiningParsa National Park is of major importance, especially for tigers andclouded leopard. Grazing animals of the grasslands include five species of deer,barasingha,sambar,chital,hog deer andmuntjac along with four large grazing animals, Asian elephant, rhinoceros,gaur andnilgai. Endangered mammals found here include thewild water buffalo and the near-endemichispid hare (Caprolagus hispidus).
The grasslands are also home to a number of reptiles including thegharial,mugger crocodile andsoft-shelled turtles.
The grasslands partly cover twoBirdLife InternationalEndemic Bird Areas, theCentral Himalayas EBA in western Nepal and the western end of theAssam Plains EBA south of Bhutan. There are three near-endemic bird species. The 44 threatened and declining bird species of the grasslands include theBengal florican (Houbaropsis bengalensis),lesser florican (Sypheotides indica),sarus crane (Grus antigone) and the elusive Indian grassbird.
Areas with tall grasslands are of special conservation importance.Woody plant encroachment is a threat to the Terai–Duar savanna and grasslands.[7]
