‘Millions’ of US birds drop dead after wildfires

‘Millions’ ofmigratory birds have been dropping dead across the southwestern United States, in amass event that scientists say is unprecedented. A sudden fall in temperature added to an earlier heatwave in some western states and a large amount of smoke from wildfires is thought to have led to amass ‘‘die-off’’, leading to people in New Mexico finding scores of birds dead on the ground. Residents of Utah and Colorado reported similar discoveries. Martha Desmond, a professor at NewMexico State University’s department of fish, wildlife and conservation ecology, said that ‘‘hundreds of thousands, if not millions’’ of birds are believed to have died. Most of the casualties are thought to be songbirds that feed on insects, flying south from north-western US or Canada to spend winter in central or southern America.