The Connecticut Post reports 30-year-old Isaias Garcia, of Garland, Texas, entered his plea Thursday to unlawful restraint.
Garcia originally faced kidnapping, assault and larceny charges in what police said was one of the strangest cases they have investigated.
Authorities say a 21-year-old man called his aunt in April to say he had been kidnapped and his abductor was demanding $800.
Police say she received a photograph of him face down in a bathtub, with an open-mouthed alligator on top of him.
Authorities later arrested Garcia at a Shelton hotel.
He faces up to one year in prison during his sentencing March 15.