The California Department of Fish and Wildlife, working with the San Diego Zoo Wildlife Alliance and Ojai Raptor Center, released necropsy results on October 14, 2026 for the Big Bear Valley bald eagle known as Jackie, logged as Patient 26-519.

Pathologists confirmed Highly Pathogenic Avian Influenza as the primary underlying cause of her decline, but in what they called an uncommon presentation: the virus caused a severe ulcer in her gizzard, the muscular stomach of a bird.

That ulcerated tissue led to persistent internal bleeding, severe anemia, and bacterial sepsis, with inflammation and blood clots also found in her heart and major vessels. HPAI genetic material was detected in tissues throughout her body, including the ulcer itself.

What makes the result remarkable is what it ruled out as much as what it confirmed. Additional testing showed Jackie was negative for West Nile Virus, and heavy metals — including lead, a notorious eagle killer — were within acceptable limits and unconnected to her decline.

Toxicology screening did detect brodifacoum, an anticoagulant rodenticide, in her liver, but the necropsy found none of the uncontrolled bleeding that rodenticide typically causes, so it was not identified as the primary cause of death.

According to CDFW, the picture was of multiple severe, interconnected disease processes developing over time. Ojai Raptor Center executive director Chris Eksteen said the results connected findings his team had watched throughout her hospitalization.

The diagnosis rested on a chain of specialist laboratories.

Toxicology and HPAI PCR testing were performed by the California Animal Health and Food and Safety Laboratory at UC Davis, with final confirmation of HPAI infection made through the USDA National Veterinary Services Laboratory system, according to the CDFW release.

Because the virus can transmit to wildlife or humans, Jackie's remains were cremated by the U.S. Fish and Wildlife Service's National Eagle Repository under established procedures.

HPAI circulates in wild bird populations across the United States, with waterfowl and shorebirds as natural hosts, and raptors like eagles can be exposed by contact with infected birds or by consuming infected prey.

Jackie's death removed one half of the iconic Big Bear Valley pair that went viral in 2023 on the Friends of Big Bear Valley livestream in San Bernardino National Forest, where she and her mate Shadow raised five eaglets together.

CDFW said that based on camera data, there is no evidence that Shadow or the eaglets were sick. Shadow remains in Big Bear Valley, and Friends of Big Bear Valley has noted he has recently been joined by another female eagle, known to fans as KD1, or "Katie."

CDFW Director Meghan Hertel said understanding these results can help inform the care and treatment of other eagles and wildlife in the future.