Jackie the eagle cause of death: How did the beloved Big Bear eagle die? What authorities revealed

Jackie was rescued in mid-July after she was found weak, underweight, disheveled and unable to fly on the north shore of Big Bear Lake.

Jackie, the famous bald eagle from Big Bear Lake, California, died early Monday morning at age 14.

Jackie's remains have been transferred to the California Department of Fish and Wildlife. (X)

She died at the Ojai Raptor Center after spending more than three weeks in intensive care. The center said her condition continued to worsen despite oxygen therapy, supportive treatment, round-the-clock monitoring and consultations with specialists.

"She remained critically ill, receiving oxygen therapy, supportive treatment, and around-the-clock monitoring in our intensive care unit," the center said in an Instagram post on Monday. "Throughout her time at Ojai Raptor Center, every decision was guided by the available medical evidence, her welfare, and our responsibility to do what was in her best interest."

What happened to Jackie?

Jackie was rescued in mid-July after she was found weak, underweight, disheveled and unable to fly on the north shore of Big Bear Lake.

She had been involved in a fight with two younger eagles. Caregivers said the encounter may have left her unable to fly, but it did not appear to be the cause of her underlying illness. Jackie showed signs that she had been sick for some time.

Extensive testing ruled out several possible causes, including lead poisoning, cancer and metal objects. Despite treatment, the exact cause of her illness remained unknown.

Jackie's remains have been transferred to the California Department of Fish and Wildlife.

"We know this news will be deeply felt by the many thousands of people around the world who have followed her journey, hoped alongside us, prayed for her, and supported the people caring for her. Our team is heartbroken. It has been an extraordinary privilege to care for her," the center added.