email a friend
printable version
Location India, Assam
Central coordinates 92o 23.30' East  26o 38.30' North
IBA criteria A1, A4ii
Area 7,881 ha
Altitude 40 - 50m
Year of IBA assessment 2004

Bombay Natural History Society

Site description Orang National Park is well known as an important habitat the Indian One-horned Rhinoceros Rhinoceros unicornis. The Park lies 18 km off the national highway from Orang town and 15 km off the highway from Dhansirimukh town. The distance from Guwahati to Orang is 140 km. The Park is situated on the northern bank of the Brahmaputra river. The Pachnoi and Dhansiri rivers flow along its eastern and western boundaries respectively. Both these rivers are tributaries of the Brahmaputra. The terrain is flat, being the floodplain of these rivers. Two distinct alluvial terraces are found: the lower Orang of more recent origin along the river Brahmaputra and the older upper Orang to its north, separated by a high bank traversing the National Park from east to west. Orang was earlier a pure alluvial grassland, probably maintained by grazing and fire by villagers. In 1915, it was declared a Game Reserve. The villagers deserted the area due to an epidemic. In 1932, plantation of fast growing local species such as Albizzia procera and Lagerstroemia flosreginae was started and some parts of the Reserve were denotified in 1928 to settle farmers from the erstwhile East Bengal under the Grow-More-Food programme. Intensive plantation was started in 1962. Along with the earlier planted local species, Dalbergia sissoo, Acacia catechu, Tectona grandis, Artocarpus chaplasha, Terminalia spp., Gmelina arborea and Bombax ceiba were planted. In 1969, Professional Grazing Reserve (PGR) areas east of the River Pachnoi were included in the Game Reserve. Mainly established to save the highly endangered Rhinoceros, the grasslands of the Park also support healthy populations of the Swamp Francolin Francolinus gularis and Bengal Florican Houbaropsis bengalensis. Lesser Adjutant Leptoptilos javanicus and Pallas’s Fish-Eagle Haliaeetus leucoryphus nest in the Park (Rahmani et al. 1990). There is also a recent record of sighting of the Bristled Grass-Warbler Chaetornis striatus (Choudhury 2000). At one time, Orang was one of the finest representatives of natural wet, alluvial grasslands of the floodplains of the Brahmaputra river (much like Kaziranga). Even now, more than 60% of the Park is under grasses such as Arundo donax, Imperata cylindrica, Saccharum spp., Cynodon dactylon, Phragmites karka and Andropogon spp. Natural forest constitutes only 2.6%, while planted forest covers 13.6% of this Park. Waterbodies (beels) and swamps constitute about 12% of the area.

Key Biodiversity 

AVIFAUNA: Orang is one of the most important sites for birds of wet, tall grasslands of the Indo-Gangetic plains. Almost all species of conservation concern are found in this small National Park of nearly 8,000 ha. During surveys between 1985 and 1989, Rahmani et al. (1990) estimated a population of 30-40 Bengal Floricans. This IBA site contains about 225 bird species (Talukdar and Sharma 1995), including rarities such as Baer’s Pochard Aythya baeri, Blyth’s Kingfisher Alcedo hercules and Finn’s Weaver or Yellow Weaver Ploceus megarhynchus. Orang is also one of the few protected areas where Finn’s Baya or Yellow Weaver Ploceus megarhynchus is found. The other wellknown site being Manas (IBA). It is considered as one of the three Outstanding IBAs of Assam (BirdLife International 2003). This site qualifies two criteria: it has globally threatened species (A1), and it has more than 1% of the population of the Bengal Florican (A4ii) criteria. Stattersfield et al. (1998) have listed three species in the Assam Plains Endemic Bird Area (EBA) (Manipur Bush Quail Perdicula manipurensis, Black-breasted Parrotbill Paradoxornis flavirostris and Marsh Babbler Pellorneum palustre). Looking at the extent of grasslands habitat, the last two species are likely to be present in this site.

OTHER KEY FAUNA: Orang NP was declared for the protection of the Rhinoceros. Between 50-60 rhinos are found here, despite intensive poaching pressure. A healthy population of Tiger Panthera tigris is maintained by herbivores such as Hog Deer Axis porcinus, Wild Pig Sus scrofa and a very large number of domestic animals that roam just outside the Park. This small area also has a small population of wild Asiatic Elephant Elephas maximus. Gangetic Dolphin Plantanista gangetica also occurs in the rivers. Chinese Pangolin Manis pentadactyla, Chinese Porcupine Hystrix brachyura, Small Civet Viverricula indica, Jungle Cat Felis chaus, Smooth Indian Otter Lutrogale perspicillata and Rufous-tailed Hare Lepus nigricollis ruficaudatus are some of the small mammals of the Park. The Swamp Deer Cervus duvaucelii population was exterminated by 1972, when license hunting prevailed (Talukdar and Sharma 1995). Old records also show the existence of Hispid Hare Caprolagus hispidus, but it is not found in Orang now. Pygmy Hog Sus salvanius, another highly endangered species, was introduced in 1976 rather unsuccessfully.

Reptiles are represented by the Indian Tent Turtle Kachuga tentoria, Brown Roof Turtle K. smithi, Malayan Box Turtle Cuora amboinensis, Eastern Hill Terrapin Melanochelys tricarinata, Spotted Black Terrapin Geoclemys hamiltonii, Indian Softshelled Turtle Aspideretes gangetica (Talukdar and Sharma 1995). All these are listed in the Indian Wildlife (Protection) Act 1972. A new species of frog, Kalophrynus orangensis, was described from Orang (Ahmed 2002).

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Swamp Francolin Francolinus gularis resident  2004  present  A1  Vulnerable 
Baer's Pochard Aythya baeri winter  2004  present  A1  Critically Endangered 
Lesser Adjutant Leptoptilos javanicus resident  2004  present  A1  Vulnerable 
Greater Adjutant Leptoptilos dubius breeding  2004  present  A1  Endangered 
Spot-billed Pelican Pelecanus philippensis resident  2004  present  A1  Near Threatened 
Pallas's Fish-eagle Haliaeetus leucoryphus resident  2004  present  A1  Vulnerable 
White-rumped Vulture Gyps bengalensis non-breeding  2004  present  A1  Critically Endangered 
Slender-billed Vulture Gyps tenuirostris non-breeding  2004  present  A1  Critically Endangered 
Bengal Florican Houbaropsis bengalensis resident  2004  present  A1  Critically Endangered 
Bristled Grassbird Chaetornis striata resident  2004  present  A1  Vulnerable 
Yellow Weaver Ploceus megarhynchus resident  2004  present  A1  Vulnerable 

IBA Monitoring

2003 high not assessed not assessed
Good - based on reliable and complete / representative data

Agriculture and aquaculture annual & perennial non-timber crops - small-holder farming happening now small area/few individuals (<10%) moderate to rapid deterioration low
Agriculture and aquaculture livestock farming and ranching (includes forest grazing) - small-holder grazing, ranching or farming happening now small area/few individuals (<10%) slow but significant deterioration low
Biological resource use hunting & collecting terrestrial animals - intentional use (species being assessed is the target) happening now some of area/population (10-49%) very rapid to severe deterioration high
Natural system modifications other ecosystem modifications happening now small area/few individuals (<10%) moderate to rapid deterioration low

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Orang National Park 7,881 is identical to site 7,881  


IUCN habitat Habitat detail Extent (% of site)
Forest   -
Grassland   -
Wetlands (inland)   -

Land use

Land-use Extent (% of site)
nature conservation and research -
Notes: Conservation
tourism/recreation -
Notes: Tourism and recreation

Acknowledgements Key contributors: Bhupen Talukdar, Anwaruddin Choudhury and Asad R. Rahmani.


Ahmed, M. F. (2002) Amphibians of Northeast India. The Rhino Foundation for nature in NE India Newsletter 4: 15-16.

BirdLife International (2003) Saving Asia’s Threatened Birds: A Guide for Government and Civil Society. BirdLife International, Cambridge, U.K.

Choudhury, A. U. (2000) The Birds of Assam. Gibbon Books & WWFIndia NE Region, Guwahati.

Rahmani, A. R., Narayan, G., Rosalind, L. and Sankaran, R. (1990) Status of the Bengal Florican in India. In: Status and Ecology of the Lesser and Bengal Floricans, with reports on Jerdon’s Courser and Mountain Quail. Final Report. Bombay Natural History Society. Pp. 55-78.

Talukdar, B. N. and Sharma, P. (1995) Checklist of the Birds of Orang Wildlife Sanctuary. Privately distributed. Guwahati.

Stattersfield, A. J., Crosby, M. J., Long, A. J. and Wege, D. C. (1998) Endemic Bird Areas of the World: Priorities for Biodiversity Conservation. BirdLife Conservation Series No. 7. BirdLife International, Cambridge, U.K.

Contribute  Please click here to help BirdLife conserve the world's birds - your data for this IBA and others are vital for helping protect the environment.

Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Orang National Park. Downloaded from on 29/10/2016

To provide new information to update this factsheet or to correct any errors, please email BirdLife