An “unprecedented” number of birds have recently died across New Mexico — and some researchers suspect the West Coast’s raging wildfires could be to blame.

Hundreds of thousands of dead birds have been found at the US Army White Sands Missile Range, White Sands National Monument in the southern part of the state, as well as other regions including Doña Ana County, Jemez Pueblo, Roswell and Socorro, according to CNN.

“We started receiving calls a week ago on Tuesday the 8th, and they haven’t really stopped since then from all across the state,” New Mexico Game & Fish Department spokeswoman Tristanna Bickford told the Santa Fe New Mexican. “We can’t say any official cause at this time. That would be pure speculation.”

Experts haven’t been able to quantify the fatalities or pinpoint an exact cause of the mass die-off.

The department’s biologists in Santa Fe have been collecting samples that will eventually be sent to the National Wildlife Health Center on Wednesday. That examination could take anywhere between two weeks and three months.

The dead birds appear to all be insectivores, with both migratory and year-round species found, according to Gail Garber, executive director of Hawks Aloft Inc.

The birds’ migratory patterns may have been disrupted due to the wildfires currently burning in California, Washington and Oregon.

Garber pointed out a migration map showing a large amount of birds leaving the Pacific Northwest on Sept. 8 and 9 and flying southwest toward Mexico through the Rocky Mountains. Normally, the birds would head south via California.

Dead migratory birds were found in the White Sands Missle Range and areas in Doña Ana County, New Mexico.
Dead migratory birds were found in the White Sands Missle Range and areas in Doña Ana County, New Mexico.Martha Desmond/New Mexico State University

Those dates also correspond with a cold snap that sent temperatures in New Mexico plunging last week.

“They could have been affected by toxins from those fires,” Garber said. “They could have been forced to leave early without enough reserves. They could have been forced into a longer journey they weren’t ready for. The cold front might have killed off insects to eat.”

“I’ve seen it suggested that millions of birds have died,” she said. “At this point, [it] will take more research to determine what happened, but it seems like it could be a perfect storm of a couple factors.”

Witnesses and researchers said some of the birds appeared to be acting bizarrely before dying — ones that usually hang in shrubs were spotted on the ground searching for food.

Swallows — which are aerial insectivores that don’t walk — were spotted on the ground of the missile range golf course, letting people approach, Desmond said.

Many appeared lethargic and were hit by cars in number “larger than ever seen before,” she said.

Bluebirds, warblers, sparrows, blackbirds, the western wood pewee and flycatchers have all be found, CNN said.

Dead birds have also been reported in Colorado, Texas and Mexico.

Martha Desmond, a professor at New Mexico State University’s department of fish, wildlife and conservation ecology, called the death toll “unprecedented.”

“It’s just terrible,” she told CNN. “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.”