Unexplained bird illness

​On Aug. 19, the Department of Fish and Wildlife Resources provided an update about the ongoing investigation of an unexplained illness affecting birds in Kentucky and elsewhere.

Kentucky Fish and Wildlife has received 2,300 reports of sick or dying birds to its online reporting system since the portal went live on June 17. The number of daily reports coming in has steadily declined since the end of June.

Staff continue to review all reports and have identified 17 new reports, in addition to the 265 previously reported during the peak of reporting, that are believed to be related to the unexplained bird illness. Many of the reported bird deaths were due to normal causes of mortality. Other reports have contained limited information and were inconclusive.

Based on its assessment to date, Kentucky Fish and Wildlife is rescinding its earlier recommendation for residents in six counties (Boone, Bullitt, Campbell, Jefferson, Kenton and Madison) to stop feeding birds.

The department strongly encourages all residents with bird feeders and birdbaths to continue cleaning them on a regular basis and to be on the lookout for any signs of disease in visiting birds. Should signs of disease appear, the department recommends taking down and disinfecting the feeders and birdbaths at that location.

At this time, a definitive cause for this bird illness has yet to be identified.

Wildlife and natural resource agencies in the District of Columbia, Maryland, Virginia, West Virginia, Delaware, New Jersey, Pennsylvania, Ohio, Indiana and Kentucky, along with federal agencies, are continuing to work with diagnostic laboratories to investigate the cause of the unexplained illness. Transmission electron microscopy and additional diagnostic tests, including microbiology, virology, parasitology, and toxicology are ongoing.

The following pathogens have not been detected in any birds tested, based on results received to date: Salmonella and Chlamydia (bacterial pathogens); avian influenza virus, West Nile virus and other flaviviruses, Newcastle disease virus and other paramyxoviruses, herpesviruses and poxviruses; and Trichomonas parasites.

Dr. Christine Casey, wildlife veterinarian with Kentucky Fish and Wildlife, said there are likely multiple factors contributing to the mortality event. The new problem appears to be complex and labs are working on understanding the possible role of bacteria and toxicology in the affected birds, she said.

"The process to determine primary versus secondary causes for the problem are important and can lengthen the diagnostic process time," Casey said.

A common disease of finches, House Finch eye disease, which has similar symptoms and is observed annually in Kentucky, does not appear to be associated with this new unexplained illness that primarily is affecting juvenile common grackles, blue jays, European starlings and American robins. Unfortunately, House Finch eye disease is common in warmer months and also appears to be circulating in Kentucky at this time.

People who observe sick house finches or goldfinches at their feeders should take down their feeders and follow the cleaning protocol outlined below.

"I've received several calls from concerned citizens noticing that birds in their yard are molting, or growing new feathers," said Kate Slankard, avian biologist with Kentucky Fish and Wildlife. "Please be assured that nearly all songbirds molt this time of year and this is completely normal."

Kentucky Fish and Wildlife continues to recommend the public follow these guidelines:

Statewide:

• Clean feeders and birdbaths weekly with a 10-percent bleach solution (one-part bleach mixed with nine parts water), rinse with water and allow to air dry;
• Avoid handling birds unless necessary. If you do handle them, wear disposable gloves. If picking up a dead bird, place an inverted plastic bag over your hand to avoid direct contact with the bird; and
• Keep pets (including pet birds) away from sick or dead wild birds as a standard precaution.
• If sick or dying birds are observed at any feeders or bird baths, the department recommends taking them down for two weeks and cleaning them in a 10-percent bleach solution.

If you must remove dead birds, place them in a sealable plastic bag and dispose of the bag in a secured outdoor trash receptacle or bury them deeply in the ground.

To read a previous update, click here.