With moderate rainfall in national Capital, the deteriorated conditions of wetlands are likely to improve. In last two weeks capital has recorded 50 mm rainfall.
Interestingly, despite being urban city, Delhi has several wetland and host winged guests from different cold areas in world.
Najafagarh, Okhla , Sultanpur , Sanjay lake, Delhi Zoo, Yamuna Bank are the various sites where migratory birds visited every year during winter months.
Najafgarh was the popular site for bird watchers but this marshland was slowly declining due to the encroachment by the locals to perform agricultural related activities.
According to Ecologists the oldest habitat for migratory birds is losing its grounds because of less rainfall and agrarian activities, however, this year monsoons season Delhi witnessed moderate rainfall.
“Wetlands are excellent rainwater harvesting sites but Najafagarh wetland area is declining. The reason of decreasing the habitat area is fishing and construction activities near the lake
“Wetlands are prominent habitat of birds and imperative for ecological system. This has been recorded during bird census practice that this year population of both migratory and resident birds has dwindled,” Roy added.
“Due to favorable environment conditions, resident birds used to come here for nesting and breeding while this season, birds have diverted their route to new adobe due to degrade condition of this wetland,” Roy further added.
According to a database, Asian Water bird Census (AWC), Annual Bird Census, have recorded that in past few years the population of migratory birds was 3,314, these birds have been spotted at the downstream drain located beyond Dwarka and Chhwala.
According to Delhi based ecologists, in previous years, the population was good because human interference was less while this year AWC recorded total 38 different species however, the total population reduced to 1481 in year 2014.
In 2015, there were only 99 Black-Winged Stilt as compared to 326 last year. Only 11 Grey Herons were sighted in 2016 as compared to 145 in 2015.
Among the winter migratory birds, 221 Bar-Headed Geese were recorded in last year while the population of Common Teal, the migratory birds from Central Asia stood at 633, Black-Tailed Godwit the migrants from North Asia were at 160.
The popular Greater Flamingo population also came down to mere 52 in 2017.
Najafgarh area came to existence as an important wildlife habitat after a local naturalist studying the area during 1986 to 1989 called attentions to it and recommending it to be conserved as a bird sanctuary.
A part from Najafagrh, Sultanpur bird sanctuary is another popular site among bird watchers. The home of 250 different bird species, the bird sanctuary welcome the cluster of new migratory birds every year.
The sanctuary which is famous for its migratory as well as native birds has 180 resident birds. Ornithologists believe that the migratory species reach in sanctuary after covering the incredible distance from native land.
Piyush Sharma, Ornithologist and wildlife photographer, Delhi said that birds come here from Europe, Siberia and Central Asia. “Birds migrate here due to inhabitable conditions like cold, temperature, snow covered grounds,” said Sharma.
Sharing the interesting facts about how birds finds the way, Sharma Said that in autumn , the adult female comes first on their nesting ground and they are followed by adult male while in spring the order is reversed. “In spring, the order is reversed..many speculations have been put forward from time to time as to how migratory birds orientate themselves,” said Sharma.
He further said that the most appropriate theory is that, day flying migrants maintain their course from the angle the sun makes with the earth, while nocturnal migrants are guided by the major constellation of starts.”
Sameer, Student, Delhi University, studying on the behavior of migratory birds said that nearly 20,000 migratory birds throng the park in winter season.
“Greater Flamingos, Ruff, Black-winged Stilt Siberian Cranes, Common Teal, Common Greenshank, Northern Pintail, Northern Shoveler, Rosy Pelican and White Wagtail are among the species which come in the sanctuary,” he said.
Red watt land, sand woodpecker are the popular migratory birds in Sultanpaur bird sanctuary, he futher said.
For the take care of migratory birds, the official at Indian Forest Department there has installed the CCTV cameras. “We manually maintain the data of visitors. To keep an eye on the activities of the people in sanctuary, the administration has installed CCTV cameras,” said a deputed government official there.