Migratory birds in the Santragachi wetland. File picture

Calcutta, Jan. 8: The state forest department today kicked off its bird census in the Santragachi wetland as a first step to formulate a conservation policy for the state?s avian visitors.

Nearly 4,500 birds of various types were identified. ?The number was much less than what used to be five years back,? said V.K. Yadav, the deputy chief wildlife warden of the forest department. A lesser number of birds, like whistling duck teals, gargenys, shovlers, pin tail ducks, cotton teals and also local species like moor hens, were found. Railway officials and the district administration representatives were also present at the Santragachi jheel today.

Based on this census, a detailed plan will be laid to give the lake a and its surroundings a face-lift by evicting encroachers and diverting the drainage and sewer outlets polluting the water body.

?Similar census will be conducted at Birbhum?s Bullavpur wildlife sanctuary on January 15,? Yadav said. Later, a bird census will also be done at Bakreswar and Tilpara barrage in Birbhum, Purbasthali in Burdwan and Phul Bari and Mahananda barrage, Rasik Bill and some other places in North Bengal. ?After this we will prepare a status report,? the forest department official said.

The census report will try to work out the migratory patterns of the birds. It will look into whether the number of birds visiting the state is increasing, the causes that make birds shift from one wetland to another and whether the birds were being disturbed in their locations and if they were being poached.

Approximately, 1,25,000 migratory birds fly every year from Siberia, China, east Europe and other parts of the world to the wetlands here. They start migrating to India from last week of November and stay here till the second week of March.

These birds, which once came to the wetlands in and around the city, are now forced to leave their area and become easy prey of poachers many a time.

Many of these birds, especially the ones which fly in from high-altitude terrain, like Ladakh, China and other parts of the Himalayas, fly 1,000 to 5,000 km. The Santragachi wetland, spread over an area of 0.817 sq km, plays host to some 6,000 to 7,000 migratory birds now.

The birds have already been pushed away from other parts of the city like the Zoo, Rabindra Sarovar, Subhas Sarobar and Nalban. There has been a 40 per cent decline in the number of migratory birds visiting the zoo. ?They do not come to Alipore because of the increase in the number of highrises, the noise and the pollution,? a forest official said.

However, pollution and change in climatic patterns are not the only causes for the decrease in the number of avian visitors, experts feel. ?These birds are facing problems in their original habitat where vegetation is decreasing and population is increasing,? said Kushal Mukherjee, secretary of Prakri ti Sansad, a voluntary organisation.