Beginning in late May, news broke about birds in Washington, D.C., and nearby states becoming sick or dying due to a mysterious ailment. The most commonly affected species were Blue Jay, Common Grackle, American Robin, and European Starling, and most of the birds were juveniles. Symptoms included crusty eyes and neurological signs such as tremors or partial paralysis.
Several states and the federal government issued recommendations that residents stop feeding birds in hopes of slowing the illness if it was being spread at feeders.
No cause has yet been discovered. Known bird diseases such as West Nile virus, salmonella, avian influenza, House Finch eye disease, and Trichomonas parasites have been ruled out. BirdWatching has not found any estimates of the number of birds that died or were sickened in this event. Nor do we know if any researcher is working on estimating the total mortality. Our questions about this to government officials have not been answered yet.
At this point, cases are no longer being reported, and the 11 states that had issued do-not-feed recommendations had all lifted the restrictions.
States that had do-not-feed recommendations were: Connecticut, Delaware, Indiana, Kentucky, Maryland, Massachusetts, New Jersey, Ohio, Pennsylvania, Rhode Island, Virginia. The directives have expired at various points since mid-August.
For more information, see this article from the Cornell Lab of Ornithology.