What killed so many of Indiana’s songbirds last year?
In the late spring and summer of 2021, Hoosiers flooded the Indiana Department of Natural Resources with reports of dead and dying songbirds.
A mystery disease found in songbirds – including the American Robin, Blue Jay, Common Grackle, and European Starling – was causing eye discharge, tremors and disorientation, an inability to fly, and death.
In June, Hoosiers were urged to take in their birdbaths and bird feeders to try and prevent the spread of the disease – advice that some counties were told to follow until early September.
People in Indiana and throughout the Midwest reported sick and dying songbirds until around September when the mysterious outbreak appeared to trickle off.
Overall, Indiana DNR received more than 700 reports of dead birds in 76 of Indiana’s 92 counties, according to Indiana State Ornithologist Allisyn Gillet.
But, that doesn’t mean that all of those birds died of the mysterious illness, Gillet told WIBC.
“These birds weren’t tested, so we can’t definitely say they had the songbird disease,” Gillet said. “I always say to be skeptical of those numbers because it might include birds with diseases that have symptoms similar to those of this disease.”
The cause of the mysterious illness is still unknown, according to Gillet.
“We actually didn’t come to a conclusion as to what was causing this disease. There were a lot of different guesses as to what might have caused it, but those are still being investigated,” Gillet told WIBC. “It’s something that is still under investigation through the National Wildlife Health Center.”
Scientists have ruled out some possible causes, including the West Nile Virus, Avian influenza, and other diseases commonly seen in the native songbird population.
Researchers at wildlife labs across the country are still studying the illness, Gillet said, and the tests involved can take a long time.
In the meantime, Gillet said she can’t rule out an outbreak of the mysterious songbird illness in 2022.
“My fingers are crossed that it doesn’t happen again,” Gillet told WIBC. “But, if it does, we’ll have more evidence to test and try to come to a better idea of what’s causing this disease. That’s the only upside. Ideally, it would be better that the birds are not suffering from these things.”