Guests under surveillance
With the bird flu assuming serious proportions, it seems that some regular guests to the country aren't very welcome. The needle of suspicion has pointed at migratory birds that visit India every winter from Siberia and eastern Europe. The birds usually arrive in October at wetlands across the country, including West Bengal. Though no deaths have been reported, the Union Ministry of Environment and Forests has put these birds under surveillance.
Migratory birds became suspects first in 2005 after a bird flu outbreak at Lake Qinghai in Western China. The pestilence claimed more than 1,500 wild birds, 90 per cent of them bar-headed geese (Anser indicus). The remaining were brown-headed gulls (Larus brunnicephalus) and great black-headed gulls (Larus ichthyaetus). These birds had a long flight range. Genetic analysis proved that one infected bird passed on the virus to the entire flock.
The Qinghai outbreak aroused fears that bar-headed geese could become permanent reservoirs of the virus and that they would carry the pathogen to their winter homes in South Asia. Indian conservationists had then downplayed this threat. "Even if the same species of migratory birds are found in India and China, flocks could be following different migratory routes,' said C K Trishal, South Asia regional coordinator of Wetlands International. A report by Birdlife International also claimed that the geographical spread of the disease did not match with migratory routes and seasons.
When bird flu struck Navapur in Nandurbar district of Maharashtra in February 2006, migratory birds were among the suspects. "Land-use changes have brought farms and wetlands closer, so wild birds