Birds ’falling out of the sky’ in mass die-off in south-western US | Environment | The Guardian
Thousands of migrating birds have inexplicably died in south-western US in what ornithologists have described as a national tragedy that is likely to be related to the climate crisis.
Flycatchers, swallows and warblers are among the species “falling out of the sky” as part of a mass die-off across New Mexico, Colorado, Texas, Arizona and farther north into Nebraska, with growing concerns there could be hundreds of thousands dead already, said Martha Desmond, a professor in the biology department at New Mexico State University (NMSU). Many carcasses have little remaining fat reserves or muscle mass, with some appearing to have nose-dived into the ground mid-flight.
“I collected over a dozen in just a two-mile stretch in front of my house,” said Desmond. “To see this and to be picking up these carcasses and realising how widespread this is, is personally devastating. To see this many individuals and species dying is a national tragedy.”
Long-distance migrants flying south from tundra landscapes in Alaska and Canada pass over America’s south-west to reach winter grounds in Central and South America. During this migration it is crucial they land every few days to refuel before continuing their journey.
Historic wildfires across the western states of the US could mean they had to re-route their migration away from resource-rich coastal areas and move inland over the Chihuahuan desert, where food and water are scarce, essentially meaning they starved to death. “They’re literally just feathers and bones,” Allison Salas, a graduate student at NMSU who has been collecting carcasses, wrote in a Twitter thread about the die-off. “Almost as if they have been flying until they just couldn’t fly any more.”