One of the longest sewage drains in Delhi — the Najagfarh drain — has become a favoured destination for both migratory and resident birds with over 75 different species flocking there this January.
The drain that passes through Najafgarh in South-West Delhi forms a huge wetland area along a 12-km stretch between Delhi’s border with Jyotigarh village in Haryana and the Chhawla Border Security Force Camp bridge. On this stretch, the water in the drain remains clean and it is only after the water body crosses Najafgarh that it turns into one of the most polluted drains of the city.
According to the 2013 report of Asian Waterbird Census (AWC), the largest and longest running internationally coordinated faunal monitoring programme in the world, nearly 75 species of birds have flocked to the drain this year despite it “not being properly maintained and mostly covered/chocked by water hyacinth”.
AWC Delhi State coordinator and ecologist T.K. Roy says the birds which have made the Najafgarh drain surroundings their home this year include “both water birds and terrestrial birds”. He said it is the presence of a large number of trees along the drain which attracts birds to this site.
“Many migratory species that have huge ecological value for maintaining a functional aquatic eco-system and natural food chain come here,” he says. But Dr. Roy is concerned about the heavy population in the vicinity of this nesting ground and how it poses a major threat to their survival.
The AWC, he says, not only estimates the water bird population but also monitors changes in their numbers and distribution and seeks to improve knowledge about little-known water bird species and wetland sites. Besides, the exercise conducted by Wetlands International-South Asia in Delhi is also part of a larger effort to identify and monitor Wetlands of International Importance under the Ramsar Convention of Wetlands so that information on the conservation status of water bird species and wetlands sites is collected and preserved.
This winter, Dr. Roy says, the presence of a total of 15 species of resident water birds, 25 species of winter migratory water birds and about 30 species of terrestrial birds have been spotted at Najafgarh drain. “Due to good rainfall during the last monsoon the wetlands expanded and attracted a good number of migratory water bird species, including some which find mention in the ‘threatened category’.”
Among the endangered or threatened species, as many as 34 oriental white ibis or black-headed ibis, which are “near threatened”, showed up while the number of migratory painted stork rose sharply to touch 121.
Migratory birds which had came to the marshlands alongside the drain included the northern shovelers (numbering 90) and northern pintails (10) that breed in North Asia and migrate in winter to East, South-East and South Asia.
Then around 98 gadwalls, which breed in Central Asia and migrate in winter to East and South Asia, 16 common coot that are residents of India, Bangladesh, Pakistan and Myanmar and migrate in winter to East, South-East and South Asia, 31 common teals and 10 Eurasian wigeons that breed in North Asia and migrate in winter to East, South-East and South Asia, 13 woolly-necked storks which are residents of South-East Asia and migrate to South Asia, 37 black ibis and 18 glossy ibis which are residents and migrants in South Asia, have been spotted in this habitat this year.
Dr. Roy says the resident water bird species have also made it in huge numbers to the habitat. “This indicates that the Najafgarh drain is a good habitat with adequate availability of food for them.”
These birds are present in much larger numbers than the migratory ones. The cattle egrets themselves have been clocked at 714, which is a huge jump over their previous spotting. Then 225 common moorhens, 66 great cormorants, 80 spotbill ducks and 110 purple swamphens have been sighted along the drain this year.