BIG BEAR LAKE, Calif., Oct. 16 (Nationwide Times) — Bird flu caused the fatal illness of Jackie, the bald eagle from California’s Big Bear Valley whose nest drew a worldwide online following, according to findings released Oct. 14, 2026, by the California Department of Fish and Wildlife and its partners.
The diagnosis identified an uncommon form of damage from highly pathogenic avian influenza, or HPAI: severe stomach injury that led to internal bleeding and bacterial infection. The findings concern one eagle, against a backdrop of the virus circulating among wild birds across the United States.
Jackie died Aug. 10 while receiving care at Ojai Raptor Center in Ojai, California, the Los Angeles Times reported.
What did the examination find?
Veterinary pathologists at the San Diego Zoo Wildlife Alliance performed Jackie’s necropsy — an examination of an animal after death to determine the cause. Her patient designation was 26-519.
“Jackie’s necropsy confirmed Highly Pathogenic Avian Influenza (HPAI) as the primary underlying cause of her decline,” said Steve Kubiski, the alliance’s director of disease investigations.
The investigation involved several laboratories. According to the wildlife department, the California Animal Health and Food Safety Laboratory at UC Davis conducted toxicology testing, which checks for poisons, and additional PCR testing for HPAI. PCR tests look for genetic material from a pathogen. The U.S. Department of Agriculture’s National Veterinary Services Laboratory system provided the final HPAI confirmation.
How did the virus make Jackie so ill?
“In an uncommon presentation of the virus, the infection caused a severe ulcer in her stomach that led to persistent internal bleeding, anemia, and the development of bacterial sepsis,” Kubiski said.
An ulcer is an open sore in tissue. Anemia means the blood has too few healthy red blood cells to carry oxygen effectively. Sepsis is a dangerous response to infection.
According to the wildlife department’s account of the examination, the damaged tissue allowed bacteria to enter Jackie’s body. Pathologists also found severe inflammation and blood clots in her heart and several major blood vessels.
Follow-up testing detected genetic material from HPAI in several tissues, including the ulcerated tissue in the ventriculus, a part of the stomach. The findings connected the viral infection with the site of the severe injury.
Was rat poison involved?
Toxicology testing detected brodifacoum, a rodent poison, in Jackie’s liver, the wildlife department said. But the examination did not identify it as the primary cause of her illness or death.
“The necropsy did not find uncontrolled bleeding typically associated with anticoagulant rodenticide; therefore, brodifacoum was not identified as the primary cause of illness or death,” the department said.
Anticoagulant poisons interfere with blood clotting. Although Jackie suffered internal bleeding from her stomach injury, pathologists did not find the pattern typical of that poisoning. Testing also ruled out West Nile virus and harmful levels of heavy metals as contributing factors, according to the department.
What treatment did she receive?
Jackie received more than three weeks of intensive care, SFGate reported. AccuWeather reported that her treatment included intensive monitoring.
The patient FAQ issued through the wildlife department identifies blood transfusion, oxygen therapy, intensive fluid therapy and anti-parasitic medications among her treatments.
How can eagles encounter bird flu?
HPAI primarily affects birds. Waterfowl and shorebirds are natural hosts of avian influenza viruses, according to the wildlife department. Eagles and other raptors — birds of prey — can be exposed through contact with infected birds or by eating infected prey.
Why was Jackie so widely known?
For more than a decade, viewers followed Jackie and her mate, Shadow, as they tended their nest near Big Bear Lake in the San Bernardino Mountains, the Associated Press reported.
Millions worldwide watched the pair through the Friends of Big Bear Valley livestream, according to AccuWeather. Shadow remains in Big Bear, the wildlife department said.
After Jackie’s death, the U.S. Fish and Wildlife Service’s National Eagle Repository cremated her remains to prevent transmission of bird flu, according to the department.
