Because they can indicate the presence of West Nile Virus, residents are encouraged to report findings of all dead birds, including their location, to the Cook County Department of Public Health's website.
Only perching birds—which include crows, blue jays, grackles, robins, cardinals, sparrows, starlings and finches—can be submitted for testing. They cannot be dead for longer than 24 hours and must be in good condition, i.e. no sign of attack, decay or road kill. If you think a bird is appropriate for testing, please contact Cook County via the link above and indicate that in your message so that the bird can be collected and frozen as soon as possible.
Birds that cannot be tested should be double bagged and thrown in a covered garbage can where they will be out of reach of pets or scavengers, which could become ill from the carcass. Use gloves or otherwise protect yourself from touching the dead bird. For your own safety, remember to wash your hands thoroughly after handling a dead bird, even if gloves were worn and there was no direct contact.