The lone protester walked up and down State Street near the entrance to Alcoa Davenport Works on Tuesday, telling anyone who would listen about President Barack Obama's "reptoid royalty" ancestry.
Richard McCaslin, no known address, happily explained his theory to Savannah Holmes, 14, of Provo, Utah, who asked to take a picture of him with his sign as the two waited for the president's motorcade.
McCaslin said he did not believe Obama to be the only alien president the United States has ever had.
"Every American president has British peerage, and royalty has always said they have the right to rule by their bloodline," he said. "Their ancestors weren't human; they were aliens, probably of the reptilian type."
McCaslin eventually moved away from the area near the entrance when asked to do so by Mark Brenny of Brenny's Motorcycle Clinic, which advertised free rides for the president.