Pittsburgh, PA – According to WESA, Pennsylvania has become the epicenter of a persistent avian influenza outbreak that has claimed thousands of wild birds across the United States, with significant impacts on species like bald eagles and waterfowl.
The resurgence of bald eagles in urban areas such as Philadelphia marked a conservation triumph after their near-extinction in the 1960s due to DDT poisoning. By 2026, the U.S. bald eagle population exceeded 315,000, thanks to the 1972 ban on the harmful insecticide. However, a new threat emerged with the ongoing avian influenza outbreak, which began affecting wild birds in 2022 and has since killed hundreds of eagles nationwide.
In Pennsylvania, the U.S. Department of Agriculture reported over 480 confirmed cases in wild birds and nearly 16 million affected domesticated birds over the past four years. In the 30 days leading up to late March 2026, six million birds succumbed to the virus. The state’s position along the Atlantic Flyway, a critical migration route from South America to the Arctic, exacerbates the spread, particularly during spring migrations when thousands of birds pass through.
Waterfowl served as primary carriers, with hundreds of snow geese dying in Pennsylvania. Other species, including Canada geese, American crows, mallards, hawks, and owls, tested positive for the virus. Raptors contracted the illness by preying on or scavenging infected birds. Research indicated that wild birds drove the virus’s dissemination across North America.
State officials intensified testing efforts to curb the disease’s impact on the poultry industry. The Pennsylvania Animal Diagnostic Laboratory at the University of Pennsylvania’s New Bolton Center operated seven days a week, collaborating with the state Department of Agriculture and Penn State University. In March 2026, Governor Josh Shapiro described the situation as a “crisis,” noting Pennsylvania accounted for half of the nation’s avian flu cases.
Agriculture Secretary Russell Redding highlighted the virus’s unexpected endurance. “This is a virus that we thought would burn out two years ago,” he stated. Instead, the strain gained strength, posing ongoing challenges.
The outbreak threatened raptor populations, including the iconic bald eagle pair nesting at the John Heinz National Wildlife Refuge in South Philadelphia, a popular winter and spring attraction. Jaclyn Rhoads, vice president of the Friends of Heinz Refuge, expressed concern over the pair’s vulnerability, especially after hundreds of Canada geese died from avian influenza across the Delaware River in New Jersey.
The USDA documented 48 bald eagle cases in Pennsylvania, but experts like Nicole Nemeth from the University of Georgia believed this underrepresented the true toll. “One black vulture that you see listed easily could represent a site where 100 or 150 other birds died,” Nemeth explained. Her 2023 study revealed high rates of nest failure and mortality among southeastern U.S. eagles, describing fatal systemic illnesses in adults and nestlings. Such findings underscored a “clear threat to raptor health” globally.
At the University of Minnesota’s Raptor Center, medical director Dana Franzen-Klein noted the virus’s stabilization, likening it to COVID-19 in wildlife. Long-term effects remained uncertain, including disruptions to breeding, migration, and lifespan. Nemeth observed chronic neurological issues in survivors, such as head tilting and brain lesions, which could persist indefinitely. While some eagles developed protective antibodies, vulnerable eaglets born annually lacked immunity.
Raptor recovery posed challenges due to slow reproduction rates—bald eagles lay only one to three eggs yearly. Neil Paprocki, a researcher on rough-legged hawks, warned that combined stressors like habitat loss and lead poisoning could keep breeding populations suppressed. The outbreak highlighted broader declines in bird species amid climate change and development.
“They can be a sentinel or a symbol for the many, many bird species that have died and are dying,” Nemeth said of eagles.
Unlike previous outbreaks that faded after one migration season, this strain persisted in wildlife ecosystems. It also infected mammals, including dairy cows, seals, skunks, raccoons, foxes, rats, and bobcats.
Wildlife rehabilitation centers in Pennsylvania faced overwhelming caseloads. The Pocono Wildlife Rehabilitation and Education Center in Monroe County admitted over 100 birds in 2026 that died or required euthanasia, down from the previous year but still demanding strict biosecurity. Executive director Janine Tancredi advised calling ahead for symptomatic birds exhibiting lethargy, seizures, or tremors.
The Schuylkill Center for Environmental Education in Philadelphia halted waterfowl admissions as a precaution. Barbara Malt of the Lehigh Valley Audubon Society recounted finding a sick great horned owl and dead Canada geese, emphasizing risks to less abundant raptors. Mass die-offs of snow and Canada geese occurred, alongside declines in black vulture sightings.
As spring migration continued into April 2026, officials anticipated further spikes, urging vigilance to protect Pennsylvania’s diverse wildlife populations from this enduring bird flu threat. For more information, visit WESA.