Mystery As Hundreds Of Thousands Of Migratory Birds Found Dead

Biologists in the US are trying to establish why hundreds of thousands of migratory birds have been found dead.

The likes of warblers, bluebirds, sparrows, blackbirds, the western wood pewee and flycatchers have been found dead across New Mexico, Colorado, Texas and in Mexico.

At first, when a large number of dead birds were discovered at US Army White Sands Missile Range and White Sands National Monument on 20 August, it was believed to be an isolated incident. But soon many more were found in Doña Ana County, Jemez Pueblo, Roswell and Socorro.

Now, biologists from New Mexico University and White Sands Missile Range (WSMR) are trying to figure out why exactly this is happening.

Martha Desmond, a professor at the university's department of fish, wildlife and conservation ecology, told CNN: "It's just terrible. The number is in the six figures.

"Just by looking at the scope of what we're seeing, we know this is a very large event, hundreds of thousands and maybe even millions of dead birds, and we're looking at the higher end of that."

People across New Mexico have reported seeing the birds behaving lethargically, getting hit by cars or sitting and allowing people to approach them.

Trish Cutler, a wildlife biologist at WSMR, told Las Cruces Sun News: "People have been reporting that the birds look sleepy ... they're just really lethargic.

"One thing we're not seeing is our resident birds mixed in with these dead birds. We have resident birds that live here, some of them migrate and some of them don't, but we're not getting birds like roadrunners or quail or doves."

One theory is that the mass death stems from wildfires in California and other western states, which may have forced the birds to migrate prematurely.

Desmond explained: "They may have been pushed out before they were ready to migrate. They have to put on a certain amount of fat for them to be able to survive the migration.

"These birds migrate at night and they get up in the jet stream, and they might migrate for three nights in succession, they'll come down and they'll feed like crazy, put on more fat and go again."

But Desmond fears the broader problem of climate change could see mass deaths like this become an increasingly common occurrence.

She said: "We began seeing isolated mortalities in August, so something else has been going on aside the weather events and we don't know what it is. So that in itself is really troubling.

"This is devastating. Climate charge is playing a role in this. We lost 3 billion birds in the US since 1970 and we've also seen a tremendous decline in insects, so an event like this is terrifying to these populations and it's devastating to see."

The birds will now be sent to the US Fish and Wildlife Service Forensics Laboratory in Oregon for necropsies to determine their cause of death, with the results expected to take several weeks.

Featured Image Credit: Martha Desmond/New Mexico State University

Topics: US News, Birds, Animals

Jake Massey

Jake Massey is a journalist at LADbible. He graduated from Newcastle University, where he learnt a bit about media and a lot about living without heating. After spending a few years in Australia and New Zealand, Jake secured a role at an obscure radio station in Norwich, inadvertently becoming a real-life Alan Partridge in the process. From there, Jake became a reporter at the Eastern Daily Press. Jake enjoys playing football, listening to music and writing about himself in the third person.

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