IN139
Bhoj wetland


Site description (2004 baseline):

Site location and context
Bhoj Wetland comprises two contiguous man-made reservoirs, the “Upper Lake” and the “Lower Lake”. The Upper Lake was created by Raja Bhoj in the 11th century by the construction of an earthen dam across the Kolans river, and the Lower Lake was constructed nearly 200 years ago, largely from the overflow of water from the Upper Lake. Both the lakes are urban waterbodies, located in the fast growing city of Bhopal, the state capital. Bhoj Wetland was designated as a Ramsar site in November 2002. The Upper Lake is surrounded by Van Vihar National Park on the south, human settlements on the east and north, and agriculture fields on the west. The Lower Lake is surrounded by human settlements on all sides. The Upper Lake is a major source of potable water for Bhopal. The Upper lake is very rich in biodiversity, particularly resident and migratory birds, macrophytes, phytoplankton, zooplankton, both natural and cultured fish species, insects, reptiles and amphibians. A management action plan has been implemented since 1995, with financial support from the Government of Japan. As part of this management plan, to follow up the impact on birds, 18-month study was undertaken in 2000-01, which helped in documenting the avifauna of the site. During this study, more than 20,000 waterbirds (A4iii criteria) were recorded. A belt of deciduous forest, with cliffs and steep contours towards the southeastern boundary comprises Van Vihar National Park. The greater part of the long western and southwestern peripheries of the site is covered with a mix of semi-desert and secondary scrub, semi-arid grassland, arable land, improved pastureland, perennial crop cultivation and forestry plantation. The extensive forestry plantation, being still young, around the lake boundaries augurs well for avian diversity in the near future.

Key biodiversity

AVIFAUNA: Nearly 179 species of birds are reported from the wetland along with the surrounding forest areas (Sharma 2002). In the peak season, the population of waterbirds exceeds 35,000 (Koustubh Sharma pers. comm. 2003). Therefore, the site qualifies A4iii criteria. Coot Fulica atra is the most numerous waterbird, followed by the Red-crested Pochard Rhodonessa rufina. In some years, its population exceeds 2,000 individuals. According to Wetlands International (2002), its 1% threshold is 1,000. The Near Threatened Black-necked Stork Ephippiorhynchus asiaticus is also seen regularly, but no nest has been found. However, a solitary juvenile was seen in the spring of 2002 (Koustubh Sharma pers. comm. 2003). Four individuals were seen, all singly. One of the most notable records is the sighting of more than 120 Sarus Crane Grus antigone. According to Wetlands International (2002), the 1% threshold of Sarus crane is 90. Therefore, this site easily qualifies A4i criteria also. Large congregations of waterfowl attract many predators such as the Pallas’s Fish Eagle Haliaeetus leucocephala and the Western Marsh Harrier Circus aeruginosus. Pallas’s Fish Eagle was seen twice in 2001.

OTHER KEY FAUNA: The Upper Lake shares its boundaries on one side with Van Vihar National Park. Unique in itself, the Park supports rich populations of Chital Axis axis, Wild Boar Sus scrofa, Nilgai Boselaphus tragocamelus and Sambar Cervus unicolor, that roam wild inside the Park. Many other animals are also kept in enclosures inside the Park, which is also a Zoo. The western and southwestern parts of the site are generally devoid of much terrestrial wild fauna, apart from the occasional sighting of Golden Jackal Canis aureus and Indian Fox Vulpes bengalensis. But due to a vast stretch of shallow water, they support huge populations of birds during winter.

More than 10 species of reptiles and amphibians; more than 40 species of fish; and around 100 species of insects have been identified in the Upper Lake (Sharma 2002).

Pressure/threats to key biodiversity
MAIN THREATS: Poaching and trapping; Siltation; Eutrophication; Influx of sewage water; Toxic waste from hospitals and factories; Use of pesticides in agriculture; Encroachment of the catchment area; Cultivation of aquatic plants.

The increasing human population of Bhopal is the most important issue. Waste produced by the ever-growing population is mixed with the drainage water that enters the lake, thus deteriorating the water quality. Though the Lake is mesotrophic, certain patches in the Lake where sewage water gets mixed, have became eutrophic. Moreover, the Lake is losing its catchment area due to human settlements and agricultural fields. This has reduced the inflow of rainwater and could decrease the water level of the Lake. Cultural activities such as the immersion of idols and tazias also pose a threat to the lake.

Acknowledgements
Key contributors: Koustubh Sharma and P. K. Nandi.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Bhoj wetland (India). Downloaded from https://datazone.birdlife.org/site/factsheet/bhoj-wetland-iba-india on 22/11/2024.