"What he consumed, we're not 100 percent sure, but at least grapes were found," Cole told the newspaper before the otter's death. "Otto exhibited initially what we thought were balance issues. He wasn't real steady on his feet and his condition hasn't improved."
"Grapes aren't part of their diet and it's not what we feed them," Cole told the Times-News. "Even the most well-intentioned efforts to feed them is not a good idea and we're dealing with the aftereffects now."
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In an update later Thursday, Bays Mountain Park confirmed Otto died. A necropsy would be conducted to determine his exact cause of death.
“Otto came to the park as a 9-month-old in October 2017 from a rehabilitation facility in North Carolina. The facility cared for Otto and his sibling after they lost their parents in the flood. The hope was to release them back into the wild, but the pups had lost their fear of humans, so Otto found a new home with us at Bays Mountain Park.
“Otto was beloved by park staff and guests alike. A cheerful creature, he could often be found swimming or playing with toys in his pool, even when it was snowing outside.
“We want to thank everyone who sent well-wishes for Otto after our initial statement earlier today.”
Cole said University of Tennessee veterinary staff will release the otter’s body back to the park next week. There will be a private burial for staff and volunteers to pay their final respects.