Claude, a rare albino alligator and the unofficial mascot of the California Academy of Sciences in San Francisco, has died at age 30, the museum announced on Dec. 2.

The alligator, whose unique appearance and calm personality dazzled millions of visitors for nearly 20 years, had been monitored by a team in recent weeks due to a waning appetite, according to the museum. He was recently moved from his swampy enclosure for treatment for a suspected infection.

Though Claude received intensive care from veterinarians and animal care teams, the museum said the "heartbreaking outcome is not what we hoped for." The UC Davis School of Veterinary Medicine will conduct a full exam and necropsy to determine the official cause of death.

"He brought joy to millions of people at the museum and across the world, his quiet charisma captivating the hearts of fans of all ages," the museum said in a statement. "We know that the magnitude of this loss will be felt in proportion to how beloved Claude was by so many across the Bay Area and beyond."

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