As of Tuesday, 99 birds have been found dead at Pong Dam lake. (Representational) Shimla: Around 100 migratory birds have been found dead in Pong Dam Lake in the last two weeks after the outbreak of a second wave of bird flu in Himachal Pradesh, wildlife officials said today. Bird flu had first been confirmed among migratory water-birds at Pong Dam Lake Wildlife Sanctuary in early January that left around 5,000 birds dead in a month. It was contained in early February but has now resurfaced since late March beginning with the discovery of a dozen bird carcasses in the sanctuary on March 25, they added.