Fred Boyce, a herpetologist from the the North Carolina Aquarium at Pine Knoll Shores was called after residents could not reach a state wildlife officer.
Deputies say when Boyce arrived he threw a towel over the alligator's head to subdue it, and that apparently agitated the reptile.
Within seconds, the alligator defended itself, knocking Boyce down and chomping down on his arm.
Boyce was treated and released at the hospital.
The alligator was eventually captured and moved to a different location.