It’s more likely than you think.
(I know the linked article refers to a singular alligator, but there are other articles behind the Statesman pay wall that state there’s evidence of at least two gators.)
(That reminds me: did you know you can get “Gator” on blu-ray? You do now. You can also get “Operation C.I.A.” on DVD, but it’s one of those “produced on demand” DVDs.)