By Darpan Singh, There's bad news for the Okhla Bird sanctuary. Because of rising pollution, local disturbances and effects of climate change, nearly 3,200 less birds visited the sanctuary this winter. The annual Asian Waterbird Census (AWC), done in January this year, has put the total number of birds sighted at 5,545. Last year, the count was 8,751. The 2013 report has been prepared by Wetlands International (South Asia). TK Roy, Delhi state coordinator of AWC, told Hindustan Times, "The decline in the number of birds is because of climate change and several other local factors and threats. Yamuna is highly polluted. Something needs to be done urgently." But the number of species that visited the sanctuary this winter has gone up from 57 to 63. Besides, nearly 35 species have registered an increase in the number of birds. These include resident, migratory and local migratory species. The numbers of some bird species - such as Greylag Goose, Barheaded Goose, Com-mon Teal, Gadwal and Eurasian Wigeon - has gone up substantially. But about 20 species have registered a decline in their numbers. Some of them are: Northern Shoveler, Common Coot, Northern Pintail, Tufted duck and Common Pochar. Moreover, three bird species - Pied Avocet, Little Stint and Little Ringed Plover - gave the sanctuary a miss this winter. What was heartening was that the Greater Flamingo (26 in all) made a comeback after 2010 and a lone Common Shelduck returned after 12 years. "Coastal birds such as Greater Flamingo used to number around 500 at the sanctuary earlier but the number came down to 20 in 2010. These rosy-white, long legged birds gave the sanctuary a miss in 2011 winter, though in an unusual development, seven of them were found in the sanctuary this monsoon," Roy said. Bird lovers are also optimistic from the fact that some threatened species - such as Oriental Darter, Oriental White Ibis, River Lapwing, Painted Stork and Black-tailed Godwit - were sighted this winter. The sanctuary - spread over an area of 3.5 sqkm on the Yamuna - is a heaven for waterbirds and a favourite among birdwatchers with more than 300 species spotted so far. After the construction of a barrage and the resulting lake in 1986, birdwatching activity increased. Source: Hindustan Times, Image: https://upload.wikimedia.org/