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Location India, Assam
Central coordinates 92o 27.00' East  24o 40.00' North
IBA criteria A1
Area 1,500 ha
Altitude 0
Year of IBA assessment 2004

Bombay Natural History Society

Site description Son beel is a large lake in Karimganj district of southern Assam. It is flanked by hills on its west and east. In winter, the extent is only a few fragmented beels, totalling less than 500 ha. It is still the largest beel in Assam but it is being reduced (Choudhury 2000) and unfortunately, there is no conservation effort to save it. The Shingla River, originating in Mizoram, is its major inlet as well as outlet. Further downstream, there is another large lake known as Rata beel, beyond which the Shingla river bifurcates into two rivers Kochua and Kakra. Son beel is accessible from Hailakandi and Karimganj towns. Barringtonia acutangula is the main tree that grows in the beel besides reeds such as Arundo donax and various aquatic plants.

Key Biodiversity 

AVIFAUNA: More than 150 species of birds have been recorded, although the actual diversity must be much more (A. U. Choudhury pers. comm. 2003). The lake attracts thousands of waterfowl, but due to constant disturbance by fishermen, they do not stay long. If properly managed, Son beel has all the potential to become a Ramsar Site, and could harbour more than 20,000 waterfowl. The Spotbilled Pelican Pelecanus philippensis and Greater Adjutant Leptoptilos dubius have stopped coming, while the Lesser Adjutant Leptoptilos javanicus is still seen.

OTHER KEY FAUNA: Not much work has been done on mammals, reptiles and amphibians of this important wetland. What we do know is that two species of otters (Lutra lutra and Lutrogale perspicillata) are found. There are unconfirmed reports of Fishing Cat Prionailurus viverrina. Hog Deer Axis porcinus is also reported but its number is much reduced due to poaching and disturbance.

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 
Lesser Adjutant Leptoptilos javanicus resident  2004  present  A1  Vulnerable 
Spot-billed Pelican Pelecanus philippensis resident  2004  present  A1  Near Threatened 
White-rumped Vulture Gyps bengalensis non-breeding  2004  present  A1  Critically Endangered 
Greater Spotted Eagle Clanga clanga winter  2004  present  A1  Vulnerable 
Slender-billed Vulture Gyps tenuirostris non-breeding  2004  present  A1  Critically Endangered 

IBA Monitoring

2003 very 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 some of area/population (10-49%) moderate to rapid deterioration high
Biological resource use fishing & harvesting aquatic resources - unintentional effects: subsistence/small scale 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 small area/few individuals (<10%) slow but significant deterioration low
Human intrusions and disturbance work and other activities happening now some of area/population (10-49%) slow but significant deterioration medium
Pollution agricultural & forestry effluents - soil erosion, sedimentation happening now majority/most of area/population (50-90%) very rapid to severe deterioration very high


IUCN habitat Habitat detail Extent (% of site)
Wetlands (inland)   -
Artificial - terrestrial   -

Land use

Land-use Extent (% of site)
agriculture -
Notes: Agriculture
fisheries/aquaculture -
Notes: Fishing
water management -
Notes: Wetland

Acknowledgements Key contributor: Anwaruddin Choudhury.


Choudhury, A. U. (2000) Birds of Assam, Gibbon Books and WWF-India NE Region, Guwahati.

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Son Beel. Downloaded from on 27/10/2016

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