Snooty, the world’s oldest captive Florida manatee, has died in an accident just one day after a big celebration to mark his 69th birthday.

The longtime South Florida Museum aquarium resident drowned after being trapped by a hatch door.

The museum’s chief operating officer Jeff Rodgers said an underwater hatch used to access plumbing equipment was somehow knocked open, prompting the aquarium’s four manatees to swim inside the tight space. While the younger animals were able to turn and swim back out, 1300-pound Snooty was unable to extricate himself.

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“Snooty was such a unique animal and he had so much personality that people couldn’t help but be drawn to him,” said the museum’s CEO in a press release. “We all deeply mourn his passing. We are honoured to have had him with us for so long and will continue his legacy through our manatee rehabilitation program.”

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Snooty the manatee seen in a July 17, 2013 file photo. AP Photo/Tamara Lush, File

According to the museum’s website, Snooty was born on July 21, 1948, and was one of the first recorded captive manatee births.

In 1966, he was moved to the newly constructed South Florida Museum, where he would go on to become a tourist attraction as well as an active participant in scientific research programs exploring how manatees hear and communicate.

Snooty was found to be able to remember things he was taught when he was just one year old, according to a Tampa Bay Times article marking his 60th birthday.

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He also played a key role in dispelling long-held myths about his species’ supposed lack of intelligence, partaking in numerous experiments that showed that manatees are far more intelligent than the small size of their brains suggests, the New York Times reported.

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But it wasn’t until 1998 that Snooty could begin enjoying the company of fellow manatees after a male orphan was introduced to his 60,000 gallon pool, the first of a rotating cast of rescued manatees to spend time in Snooty’s tank as part of their rehabilitation for return to the wild.

Unlike his tank-mates however, Snooty was always destined to live out his life in captivity because he wasn’t born in the wild.

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