Northern Cardinal at feeder. Photo by Pat Ready
As of March 2022 (will only update if there are changes to these recommendations): To date, the cause of the illness is still unknown. Cases declined throughout the summer elsewhere and the illness has not reported in Wisconsin. Madison Audubon is recommending people resume feeding birds clean feeders and baths regularly, and remain vigilant for sick birds with the illness symptoms. See below for more information.
Madison Audubon closely followed the reports from the USGS National Wildlife Health Center and researchers across the United States studying the mystery illness affecting birds (original post here). Unfortunately, the cause remains unknown, but reported cases dropped during summer (for example, they decreased 50% in Virginia).
It is possible that the reduction in cases could be attributed to people following suggested preventative measures, such as taking down feeders and baths. It's great to feed birds, and we enjoy seeing them, but feeders are only supplementary this time of year. Wild plants, seeds, fruits, insects, and more are abundant in the summer, so birds have access to a plentiful supply of food.
In Wisconsin, there have not yet been any confirmed cases of birds sickened or killed by the mystery illness and we're hoping that we can work together to keep it that way. With this in mind, our updated recommendation for those who wish to have their feeders up is to be vigilant about cleaning them (this is a best practice under all circumstances). Take the following steps at least once every 1-2 weeks:
Empty feeders and sweep up any fallen seed
Clean with a 10% bleach solution (one part bleach mixed with nine parts water) and rinse thoroughly with water
Allow to air dry completely (in the sun if possible) before filling with fresh seed and rehanging
We also recommend that people continue to clean their bird baths every 1-2 days with a 10% bleach solution, allow them to air-dry, and refill with clean, fresh water.
As a reminder, if you find a sick or dead bird that has characteristic symptoms of the mystery illness (swollen or crusty eyes, twitching or other neurological symptoms):
Remove your feeders and baths if the bird was found in your yard.
Report it to your local DNR conservation biologist or wildlife biologist.
Keep pets and people away from sick or dead wild birds as a standard precaution.
Avoid handling any sick birds unless necessary. If you must handle a sick bird, wear disposable gloves and place an inverted plastic bag over your hand to avoid direct contact with the bird.
We will continue to follow updates from researchers and other organizations, and will provide updated suggestions for how to protect our birds as soon as we have them.
