Bird flu was the main cause of Big Bear eagle Jackie's death, necropsy finds

What the necropsy found

Jackie, the bald eagle whose Big Bear Valley nest drew a worldwide livestream audience, died primarily because of highly pathogenic avian influenza, the California Department of Fish and Wildlife said on Wednesday, October 14. The department released the final necropsy findings together with the San Diego Zoo Wildlife Alliance, whose veterinary pathologists performed the examination, and the Ojai Raptor Center, which treated the eagle before her death. ^{[1] [3]}

According to the department, the infection caused a severe ulcer in the ventriculus, the muscular stomach also known as the gizzard. That ulcer led to persistent internal bleeding and severe anemia, and the damaged tissue allowed a secondary bacterial infection that progressed to sepsis. Pathologists also found inflammation and blood clots in her heart and several major blood vessels, and detected the virus's genetic material in several tissues, including the ulcerated stomach tissue. ^{[1] [4]}

Steve Kubiski, director of disease investigations at the San Diego Zoo Wildlife Alliance, said the necropsy confirmed avian influenza "as the primary underlying cause of her decline." He described the case as an "uncommon presentation" of the virus, KESQ and Victor Valley News reported. ^{[1] [3] [4]}

What was ruled out

Additional laboratory and toxicology testing ruled out several other possible causes. Tests for West Nile virus were negative, and lead and other heavy metals were within acceptable limits and not linked to her illness, the department said. ^{[1] [2]}

Toxicologists did detect brodifacoum, an anticoagulant rodenticide, in her liver. Investigators concluded it was not the primary cause because the necropsy did not show the uncontrolled bleeding typically seen in rodenticide poisoning. Testing also found persistent environmental contaminants, which the department did not connect to her death. ^{[1] [4]}

Weeks of treatment

Jackie, estimated to be about 14 years old, was seen fighting two younger eagles in July and was later rescued from the Big Bear Lake shoreline, CBS Los Angeles reported. Smithsonian magazine reported that Los Angeles County Parks' San Dimas Raptor Rescue picked her up and took her to the Ojai Raptor Center, where staff found no physical injuries but noted she was very thin. ^{[2] [5]}

At the center she was diagnosed with severe anemia, received a blood transfusion and underwent further tests, but the cause of her illness was not identified while she was alive. She died early on August 10 after more than three weeks of intensive care, according to KESQ, KVCR and Smithsonian. ^{[3] [5] [6]}

Chris Eksteen, executive director of the Ojai Raptor Center, said the necropsy results helped connect many of the findings seen during her hospitalization. CDFW Director Meghan Hertel said, "The story of the Big Bear bald eagle reflects the powerful connection people feel to these iconic birds," and added that the results can inform future care for eagles and other wildlife. ^{[1] [4]}

Shadow and the nest

Following procedures meant to prevent the spread of avian influenza, Jackie's remains were cremated by the U.S. Fish and Wildlife Service's National Eagle Repository, the department said. ^{[1] [2]}

Jackie and her mate Shadow became widely known through a 24-hour nest camera run by the nonprofit Friends of Big Bear Valley. Their most recent eaglets were Sandy and Luna, according to CBS Los Angeles and KVCR. Shadow remains in Big Bear Valley, and CDFW said camera data shows no evidence that Shadow or the eaglets were sick. ^{[1] [2] [6]}

Since her death, Jackie has been honored with a memorial service in Big Bear and a life-size monument in a San Bernardino Mountains park, and California legislators passed a resolution declaring September 4 as California Wildlife Day in her honor, CBS Los Angeles reported. ^[2]