Since May of this year, some states, including NJ and PA in our region, have experienced a bird mortality event affecting young songbirds (nestlings and fledglings). A recent press release by the New …
Since May of this year, some states, including NJ and PA in our region, have experienced a bird mortality event affecting young songbirds (nestlings and fledglings). A recent press release by the New Jersey Division of Fish and Wildlife details observed symptoms: “Some (but not all) of the affected birds are showing neurologic signs consisting of head tremors, leg paresis (partial paralysis or weakness), ataxia (falling to the side) or inability to stand at all, and excessive vocalizations. Also, most of the birds are in good body condition—likely still being fed by their parents.”
The most commonly affected species are passerines, songbirds such as robins, cardinals and blue jays, as well as starlings. A cause of this event has not been found yet; agencies of affected jurisdictions are cooperating in finding the cause.
None of the following pathogens have been detected in any of the birds tested: salmonella and chlamydia (bacteria), avian influenza virus, West Nile virus, coronaviruses, Newcastle disease virus, herpesviruses, poxviruses and trichomonas parasites. Toxicology tests for heavy metals and pesticides/herbicides have come up negative.
As time went on, there were fewer numbers of affected birds reported in Pennsylvania. Also, there has been no indication that the cause of the bird mortality is affecting any other animals or humans.
On August 13, the PA Game Commission (PGC) issued a press release lifting the recommendation to cease feeding birds and maintaining birdbaths. There was no evidence that having birds congregating at a feeder increased the chance of them being affected. They also recommend that people continue to be vigilant for the appearance of sick or dead birds and contact their nearest PGC office.
If you maintain a bird feeder or birdbath, the PGC recommends that you clean it at least once a week as a preventative measure for more common maladies. This link from Audubon has some cleaning tips as well as some other bird feeding ideas: https://auduboninternational.org/wp-content/uploads/2019/03/WHM-Bird-Feeding.pdf.