Redneck Gators were alligators who had been mutated by moonshine spilt by some of the locals into their swamp habitat. The Gators were larger than regular alligators, had a reddish coloration, lots of spikes protruding from their backs, and were able to shoot spines from their tails.
While the original Gators were created by mutation from the toxic moonshine, any person whom they bit would slowly transform into a Redneck Gator themselves, keeping some indications of whom they had been originally (for example, one Gator retained the gold tooth that he had possessed when human).
In addition, at least one of the Gators retained his human side when he fought another Gator to protect the woman he had loved as a person. This gator later lived with the woman in her house on the bayou.