The illness that is killing birds in Kentucky and nationwide still isn’t identified, according to a statement released by the Kentucky Department of Fish and Wildlife Wednesday.
National wildlife agencies and officials in affected states have ruled out some common bird illnesses like salmonella and chlamydia, avian influenza virus, West Nile virus and other viruses and parasites.
They have also confirmed that the illness is not House Finch eye disease. Though the illness and House Finch eye disease have similar symptoms, the two do not appear to be associated.
House Finch eye disease occurs naturally in Kentucky during warmer months and cases have been reported this year. However the new illness is affecting primarily juvenile common grackles, blue jays, European starlings and American robins.
Eliminating specific illnesses from the list of possibilities has not brought researchers much closer to figuring out what is causing the deaths.
“The new problem appears to be complex and labs are working on understanding the possible role of bacteria and toxicology in the affected birds,” said Dr. Christine Casey, wildlife veterinarian with Kentucky Fish and Wildlife.
The department opened a reporting portal in June. Since then, they received more than 2,000 reports of dead birds, but believe only about 265 of those are related to the mystery illness.
In Kentucky, residents of Boone, Bullitt, Campbell, Jefferson, Kenton and Madison counties are advised to take down their bird feeders, so that birds do not congregate and spread the illness.
Residents in other parts of the state are recommended to frequently clean their bird feeders and baths.