A Chronicle-News reader described an unsettling scene. Nearly every day recently she was collecting small dead birds in her Trinidad yard.
“It was disturbing that first day,” said Tammy Schuster. “They just fell from the sky and then I’d find four, or five in one day. I must have collected a couple dozen in my itty-bitty yard.”
Wildlife officials collected some of the dead birds from Schuster’s property. On Wednesday, Oct. 7 Schuster reported that the day before was the first day she didn’t find a bird and said the deaths thankfully seem to have slowed, at least in her corner of the world, according to her and her neighbors.
She is not alone in her grisly discovery. Reports of huge numbers of migratory birds dropping dead from California to Colorado and New Mexico have been made and scientists are scrambling to determine what is triggering one of the Southwest’s largest bird die-offs in recent memory.
After people began finding the dead birds in recent weeks the mystery of what is causing the die-off has intensified.
Biologists are examining whether wildfires may be a factor in the deaths, with smoke plumes potentially altering migration routes or increasing the toxins inhaled by birds.
Meanwhile, researchers at universities are also looking at other possible factors, such as a recent cold snap in the Mountain West or the drought in the Southwest that has depleted the insect populations that are a source of food for many migratory birds.
One of the first alerts about the die-offs came on May 20, when a report described a sharp increase in dead birds found at the White Sands Missile Range in southern New Mexico.
“I’ve never seen anything like this in New Mexico in recent times,” Martha Desmond, a professor in New Mexico State University’s department of fish, wildlife and conservation ecology told the Associated Press.
Desmond and other researchers have fielded reports of dead migratory birds found in many parts of New Mexico, southern Colorado and West Texas. Desmond said the numbers of dead birds in the region could easily number in the hundreds of thousands.
Andrew Farnsworth, a senior research associate at the Cornell Lab of Ornithology, told reporters that the die-off began before the sharp drop in temperatures across the region in September. He added that the deaths amounted to “clearly a major, major event” in the broader problem of migratory birds being killed, often by cats or by crashing into man-made structures.
“It’s different this year than other years,” Farnsworth said, adding that he believed that the wildfires could be a potential trigger for the bird deaths. “We’ve had plenty of hot summers but very few that have had these huge-scale fires combined with heat combined with drought.”
Arvind Panjabi, an avian conservation scientist with the Bird Conservancy of the Rockies in Fort Collins said, “These birds are not crawling into a bush to die. They’re being left exposed where they simply couldn’t take another flap,” Panjabi said. “These are very unusual and conspicuous locations for birds.”
Jason Clay, spokesman for Colorado Parks and Wildlife, said reports have mainly come in the Durango, Gunnison and San Luis Valley area, but that officials have not seen the “catastrophic die-off” that’s been the case in New Mexico.
“We speculate mortalities were more in the dozens than the thousands,” Clay said in a report.
National wildlife officials said this type of event is not unprecedented, given the enormous temperature drop. The severe weather disrupted birds’ migration routes, forcing them to fly into areas where water and food were limited said a spokesman for the U.S. Fish & Wildlife Service.
Researchers have described the birds as in very poor body condition, suggesting starvation/exposure.
Regardless of the reason, experts say the sudden deaths could impact bird species that are already seeing precipitous declines in population over the past 50 years as their habitat disappears and climate changes transform the ecosystem.
— Anyone who encounters a dead or ailing bird is urged to proceed with caution. Use gloves if you must handle the bird and always follow the directions of game and fish authorities. People that find dead birds are also encouraged to submit details to the Southwest Avian Mortality Project.