|Most recent IBA monitoring assessment|
|Year of assessment||Threat score (pressure)||Condition score (state)||Action score (response)|
|2013||very high||very unfavourable||medium|
|For more information about IBA monitoring please click here|
Delhi and the neighbouring state of Uttar Pradesh harbour a huge wetland refuge for birds. The site is located at the point where the River Yamuna leaves the territory of Delhi and enters the neighbouring state of Uttar Pradesh. The most prominent feature of the Sanctuary is a large lake created by damming the river, which lies sandwiched between Okhla village towards the west and Gautam Budh Nagar towards the east (Urfi 2003). So rich is this stretch of the river in avian diversity that it could well qualify as a Ramsar wetland of international importance. However, various development activities such as the construction of the NOIDA-Delhi freeway are encroaching on prime habitats of several birds. The Uttar Pradesh (U.P.) side of Okhla has already been declared a bird sanctuary. This Sanctuary comes under the Irrigation Department. The aquatic vegetation of this stretch of River Yamuna has been described by Gopal and Sah (1993). Typha and Phragmites reed beds are abundant, especially during monsoon. Patches of Water Hyacinth Eichhornia crassipes form dense mats. Salvinia is also found. The common tree species are Acacia nilotica, Acacia modesta, Albizzia lebbeck, Dalbergia sissoo, Zizyphus mauritiana, Ficus bengalensis and F. glomerata.
AVIFAUNA: Since the creation of a barrage on the river in 1986, and the resultant waterbody, the bird life has shown tremendous increase. Urfi (2003) has compiled a list of 302 bird species from this site. An additional 27 species have been listed by Harris (2001) as probable. They need confirmation. During winter, between 14,000 to 20,000 waterbirds are recorded. This site qualifies in A4iii criteria (i.e. the site is known or thought to hold = 20,000 waterbirds). The total Okhla list includes two Critically Endangered species, nine Vulnerable species, seven Near Threatened species and one Conservation Dependent species. Some species, such as Baikal Teal Anas formosa, Greater Grey-headed Fish Eagle Ichthyophaga ichthyaetus, and Bristled Grass-Warbler Chaetornis striatus have not been seen in recent years (see Urfi 2003, for more details). Among the resident birds listed in the Table, which are of great concern to us than vagrants, the Sarus Crane Grus antigone has declined all over India during the last two decades (BirdLife International 2001). Prior to 1992, pairs were sighted sporadically from the agricultural fields and marshes outlying Okhla lake area. One such area has now been destroyed by a newly built motorway. Since then, there has been no sighting of Sarus from Okhla (Urfi 2003). The Indian Skimmer Rynchops albicollis that has declined all over its range (BirdLife International 2001), was found frequently in summer in the Yamuna river system in the mid 1970s (Ganguli 1975) but now it is a rare visitor to Okhla (Harris 2001), with flocks of up to seven sighted in August 1998, January 2001, and August 2001. The Lesser Adjutant Leptoptilos javanicus has also not been sighted during the last 10 years. Urfi (2003) noted six birds in February 1990, but there has been no other recent record (Harris 2001). However, the Near Threatened Black-necked Stork Ephippiorhynchus asiaticus is still holding on. Up to five birds were seen in Okhla during 1989-1992 (Urfi 2003), and three birds in September 1990 (Harris 2001). Records of nest-building activity by the Vulnerable Yellow Weaver or Finn’s Baya Ploceus megarhynchus has been a topic of discussion. It is a bird of the terai region of Uttar Pradesh and Assam (Ali and Ripley 1987, Grimmett et al. 1998). Rai (1979) has recorded it breeding in Hastinapur WLS (an IBA) in Meerut district. They could have come from there. There has been no recent sighting from Okhla or other areas in the Yamuna. The Okhla barrage is an important feeding ground for the 300 to 500 Painted Storks Mycteria leucocephala that breed in Delhi Zoo (Urfi 1997, 2003). Several migratory species visit the river in large numbers in winter, with the commonest ducks being the Northern Shoveller Anas clypeata and Gadwall Anas strepera. The Northern Pintail Anas acuta and Ruddy Shelduck Tadorna ferruginea are also common. Other common species include the Common Teal Anas crecca, Tufted Duck Aythya fuligula, Common Pochard Aythya ferina, Greylag Goose Anser anser and Bar-headed Goose Anser indicus. The resident Spot-billed Duck Anas poecilorhyncha is abundant. The Garganey Anas querquedula is a fairly scarce passage migrant, along with the Common Shelduck Tadorna tadorna, Comb Duck Sarkiodiomis melanotos, and Indian Cotton Teal or Pygmy Goose Nettapus coromandelianus. The Red-crested Pochard Rhodonessa rufina and Mallard Anas platyrhynchos occur in small numbers. Other species that have occasionally been seen in the area include the Black Bittern Ixobrychus flavicollis, Asian Openbill Anastomus oscitans, White-necked Stork Ciconia episcopus, Large Whistling Duck Dendrocygna bicolor and Ruff Philomachus pugnax. The very rare Bristled Grass-Warbler or Grasssbird Chaetornis striatus has also been sighted here (Grewal 1996). Yet, the area where the Bristled Grass-Warbler was found has been destroyed by the NOIDA toll bridge. In November 2000, more than 450 Greater Flamingos Phoenicopterus ruber were observed and there have been sightings of large flocks of flamingos throughout. Okhla has been identified as an IBA in view of its bird life and the presence of globally threatened species such as the Sarus Crane, Bristled Grass-Warbler, Greater Spotted Eagle, and Indian Skimmer. The non-sanctuary area on the Delhi side has also been assigned IBA status on the basis of IBA criteria A1, A3 and A4i.
OTHER KEY FAUNA: There are no large or small mammals of conservation concern. On the Delhi side, the Sanctuary is surrounded by a bustling market and residential area, while on the Uttar Pradesh side, sometimes a few Golden Jackals Canis aureus and an occasional Nilgai Boselaphus tragocamelus are seen. Not much is known about the reptile, amphibian and fish fauna.
BirdLife International (2020) Important Bird Areas factsheet: Okhla Bird Sanctuary. Downloaded from http://www.birdlife.org on 09/07/2020.