Jackie’s blood transfusion brought improvement, but it didn’t bring an answer. Her red-cell levels rose, she began eating independently again, and her medical team kept searching for the illness that was leaving her so dangerously anemic.

Now, an investigation completed after her death has identified highly pathogenic avian influenza, or HPAI, as the primary disease behind her decline. For the bald eagle whose life with Shadow at Big Bear unfolded on camera, the findings explain something the nest stream and hospital updates couldn’t show: the damage developing inside her body.

On October 14, 2026, the California Department of Fish and Wildlife released findings from a necropsy performed by San Diego Zoo Wildlife Alliance’s veterinary pathologists and subsequent laboratory testing. They connect bird flu with severe stomach ulceration, continuing blood loss and a secondary bacterial infection.

The central damage involved the ventriculus, the muscular stomach also called the gizzard. Its ulcerated tissue was bleeding and allowed bacteria to spread beyond the digestive tract. Investigators also found inflammation and clots affecting the heart and major blood vessels.

Those findings give a different perspective on the hopeful and discouraging changes recorded during her hospitalization.

Jackie arrived at Ojai on July 18 after she was found unable to fly. She was dehydrated and underweight, but her examination didn’t reveal fractures, wounds or another major traumatic injury that explained her condition. Her blood, however, showed an immediate emergency.

Her packed cell volume, or PCV, measured 10%. That figure describes the share of blood occupied by red cells. Ojai’s medical journal says a healthy bald eagle would generally have a value above 30%. The team needed to support her while investigating what was causing the shortage.

When her PCV dropped to 8%, she received blood from Spirit, a nonreleasable bald eagle at the California Living Museum in Bakersfield. The transfusion supplied circulating red cells while the search for a diagnosis continued. Her PCV subsequently reached 12%.

There were further setbacks, then more encouraging changes. By July 26, the value had reached 14%, and Jackie was alert and feeding herself. A 16% reading followed on July 27. Her blood samples also contained signs of newly produced red cells.

During her final decline, her PCV fell below 6%. She stopped feeding herself and couldn’t retain assisted feedings. Ojai’s current medical journal records her death during the evening of August 9, 2026. The public announcement followed on August 10.

Why some answers came only after her death

A necropsy opens an investigation that scans and blood samples can’t complete. Pathologists can examine organs, inspect tissues under a microscope and compare laboratory findings with the medical record. Some results require further tests, extending the investigation beyond the initial examination.

In its expanded medical FAQ, Ojai describes initial tests that couldn’t isolate the virus. Targeted testing of diseased tissue after Jackie’s death supplied the confirmation. Several typical HPAI lesions were absent, and routine postmortem swabs contained little viral material compared with affected internal tissues. An atypical presentation doesn’t, by itself, establish a new strain.

Marrow examination also found that developing red cells weren’t maturing normally. Ongoing stomach bleeding and impaired maturation helped explain the persistent anemia.

The toxicology findings need similar care. Brodifacoum, an anticoagulant rodenticide, was detected. It wasn’t identified as the primary cause, although Ojai says a contribution to the illness’s severity can’t be excluded. Testing also found environmental contaminants, including PCBs and DDE, a breakdown product of DDT.

West Nile testing was negative. Lead and the other heavy metals tested were reported at acceptable levels, without a link to the disease progression.

A positive toxicology result and a diagnosis answer different questions. Finding a substance establishes exposure; determining what it did requires the rest of the evidence. Here, the investigators identified HPAI as the principal underlying disease without declaring every other possible contribution impossible.

The findings don’t establish exactly when or where Jackie acquired the infection. Nor can they tell us precisely how much infectious virus she shed during treatment. Ojai reports no evidence of transmission associated with her care. The center also says the pathology didn’t link her deterioration to handling or diagnostic tests.

CDFW reports no camera evidence of illness in Shadow or the eaglets. Observations aren’t laboratory tests, so that statement shouldn’t become a claim that the birds tested negative.

CDFW confirmed that Jackie’s remains were cremated by the National Eagle Repository as a precaution against HPAI transmission. The announcement doesn’t describe the subsequent disposition of her ashes.

The findings arrive after Jackie’s October memorial in Big Bear, adding a medical explanation to a life already commemorated through photographs, artwork and gatherings.