On Tuesday approximately 100 seasonal birds have been discovered dead in Pong Dam Lake in the last two weeks following the outbreak of a second wave of bird flu in Himachal Pradesh. Bird flu had first been confirmed between nomadic waterbirds at Pong Dam Lake Wildlife Sanctuary at the beginning of January that left around 5,000 birds died in a month. It was contained in February but has presently resurfaced since late March beginning with the discovery of a dozen bird carcasses in the sanctuary on March 25, they added.
Chief Wildlife Warden Archana Sharma stated that the National Institute of High-Security Animal Diseases (NIHSAD) in Bhopal has verified the occupancy of H5N8 avian influenza with the specimens of the dead birds. This fear is different from the first outbreak when H5N1 had been recognized among the migratory birds, she said continuing that both these strains are extremely pathogenic. Earlier this year, when bird flu outbreaks were reported over India, most of the states including adjacent Haryana reported the H5N8 subtype of the virus, a strain that has not been identified to affect humans.
99 birds have been found dead at Pong Dam lake during this resurgence, on Tuesday she added. Similar to the previous outbreak, most of the sufferers are bar-headed geese, she said continuing that the dead birds also cover nine greylag geese. The outbreak has so far been restricted to two neighboring forest beats and bird fatalities are higher during days of unfavorable weather because that is when the geese manage to flock together rather than flying out, leading to more transmission of the virus, she added.
An international Ramsar site with a region that stretches up to 220 square kilometers during the wet season, the Pong wetland becomes home to flocks of seasonal waterfowl each winter when wetlands in Europe, north, and central Asia become iced. A bird census in the sanctuary in February revealed the appearance of over one lakh migratory waterbirds of 51 different varieties at the lake, including over 40 thousand bar-headed geese. With the start of summer, the migratory birds are now crossing back to their parent wetlands, she added. Many of the birds now present in the lake are those which have traveled from Rajasthan and other parts of the country, halting here on their northward journey, she said.
Some events of deaths of other birds have also been recorded from other parts of the state, including Theog in Shimla district and Manali in Kullu district, and their specimens have been taken for testing by the animal husbandry department. Meanwhile, the sanctuary has again been closed for visitors, and the bird flu action plan has been stimulated, which involves surveillance, testing, and scientific disposal of dead birds, she added.