‘Millions’ of US birds drop dead after wildfires

‘MILLIONS’ of migratory birds have been dropping dead across the south-western United States, in a mass 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 a mass “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 New Mexico 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.

Andrew Farnsworth, a senior research associate at Cornell University’s ornithology lab, called the dieoff a “major, major event”.

“Impacts from climate change are wreaking havoc in different systems, and this is unfortunately one of the kinds of things that we might see more and more of.”

Jon Hayes, executive director of conservation at the New Mexico office of The National Audubon Society, a non-profit group, said he had encountered dozens of birds in Albuquerque, the state’s largest city.

“I’ve never seen anything like this. You get high mortality rates during migration. It’s a particularly hard time for all bird species, but you don’t ever see any more than just one dead bird,” he said.

Usually, die-offs are caused by disease or a specific event, such as an oil spill. But the unprecedented scale of this event has led scientists to believe that environmental factors are to blame.

Many of the birds would have flown through areas in Oregon, Washington and California that have been affected by wildfires this year.

Birds are thought to be particularly vulnerable to particulates and polluted air.

Extremely high summer temperatures across the western US are also thought to have impacted the birds’ ability to survive, as well as dry conditions in New Mexico that have impacted the insects they feed off.