With just six species of water birds being spotted on the Wazirabad Barrage-Nizamuddin Bridge stretch of the Yamuna in Delhi this year, the Asian Waterbird Census (AWC) 2012 has raised serious concerns about the degradation of natural habitat for the birds due to a variety of reasons.
AWC’s Delhi State Coordinator T. K. Roy, who led a team of volunteers to conduct the census from January 14 to 29 with the help of forest staff of Okhla Bird Sanctuary, says some of the findings are very disturbing.
For one, the arrival of water birds along the Wazirabad Barrage-Nizamuddin Bridge stretch of the Yamuna has diminished sharply over the past five years. While in 2008, as many as 20 species of migratory birds were spotted along this stretch, the number has dropped to just six this year.
Even among these six species, only a pair each of common sandpiper, red wattled lapwing and grey wagtail were spotted. “Due to various levels of threats in the river, the bird habitat in Delhi, the resident bird species have almost disappeared and regular migratory water bird species too have abandoned the river habitat,” says Mr. Roy.
He says this year hardly any winter migratory species has been spotted except small flocks of black-headed gulls, brown-headed gulls and black-winged stilts.
These birds too were seen more towards the beginning of winter when they came in search of food.
But later, they sheltered in the much upper stretch of Yamuna near Hindon and in the smaller floodplain wetlands adjacent to the Yamuna due to habitat shrinkage and shortage of food, primarily fish, he adds.
Part of the largest and longest running internationally coordinated faunal monitoring programme in the world for many years now, Mr. Roy says the census has also narrowed down on the reasons for the decline in the arrival of water birds.
The main reason for their staying away from the Wazirabad Barrage-Nizamuddin Bridge stretch of the Yamuna has been fishing, cutting and clearance of vegetation, vegetable cultivation and human disturbance, presence of open crematorium, dumping of non-biodegradable waste, concrete urban developments on riverbed and water pollution caused by flow of sewage and industrial effluents.
As for the Okhla Bird Sanctuary, Mr. Roy says this year 13 species of major migratory water birds (ducks, geese, coots), 11 species of waders, four species of gulls, three species of storks, three species of ibises, three of wagtails and 25 of resident water birds have been recorded.