VAIL, Colo. (CBS4) – The fire season along with an early burst of cold weather this month may be contributing to an unusually high mortality rate for migratory birds.
“The strangest thing was during our last snowfall, hundreds of warblers arrived right here on Gore Creek and were ravenous looking for insects. I’ve never seen anything like that,” said Kim Langmaid, founder of the Walking Mountain Science Center.
Langmaid has been an avid bird watcher her entire life. She’s also a professor of sustainability for Colorado Mountain College, and her students have taken notice of the situation, too.
“My students have told me they’ve seen tens and tens of dead birds right after that snowstorm so as they were walking on the trails or hiking, just seeing dead birds all around the community,” she said.
Over the last month, bird watchers have been reporting unusually high deaths of songbirds in across the state. According to Inaturalist, a joint initiative between the California Academy of Sciences and National Geographic, has received thousands of similar observations from bird watchers across the state.
It created the Southwest Avian Mortality Project, in August. In Colorado, users have been submitted observations from Denver to Durango.
Colorado Parks and Wildlife says its veterinary team has been analyzing carcasses from the recent deaths, and while there isn’t a lot of data available yet, they are learning.
“We received a few western wood pewees, bluebirds, and warblers. All have been in very poor body condition suggesting starvation/exposure. All of the carcasses sent appeared to have died within the week following the early September snowstorm.”
Early reports suggest the die-off began even before temperatures plummeted, and experts suspect smoke from an active fire season played a large role.
“If you think 2020 is a tough year for people, try being a migratory songbird. These small birds that move back and forth annually between North and South America have been hit by several environmental factors that have formed a bird’s worst-case-scenario. Drought has made for a tough summer. Follow that with a freak early winter storm system that prompted migration before many birds were physically ready and it’s bad enough. Throw in the heavy smoke from wildfires and it is more than many of these birds can handle,” said Randy Hampton, Public Information Officer with CPW’s Northeast Region.
For Langmaid, it’s an important opportunity to learn more about what it means for the environment.
“Scientifically it tells us a lot about our natural environment; it tells us about the quality of the air, it tells us about the quality of the habitat and the insects that the birds forage for,” she said.
Hampton said biologists believe the bird population can bounce back, thanks to protections for migratory species that have been put into place, but as fires continue to intensify, it will become more difficult.
This year, fires across Colorado began in peak migratory season for the songbirds. Currently, experts are trying to learn how the smoke may have played a role in route finding among many other things.
“Huge forest fires are gonna be challenging but we can certainly work on maintaining the landscapes and provide safe refuge for these birds as they’re migrating,” said Langmaid.
Scientists say every observation helps them learn more. For more information on the Inaturalist Southwest Avian Mortality project, click here.