Oldest known male dolphin in captivity passes away in Vallejo

VALLEJO, Calif. (KGO) -- The oldest known male bottlenose dolphin passed away under human care in Vallejo. Semo was 54 years old and lived at Six Flags Discovery Kingdom. The park is in mourning.

According to a release from the park, Semo was an animal ambassador to millions of guests and brought joy to many who visited the park.

"Semo was a ruggedly handsome, large and imposing male, who was also infinitely joyful and playful," said Animal Care Director, Dianne Cameron. "We feel so fortunate to have been a part of his life."

Semo came to the park in 2012 after living at the Minnesota Zoo. Prior to that, he lived at Sea World for many years.

Although his cause of death is still pending, officials believe he passed due to old age.

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