While working on homing experiments with gulls at Rogers City, Presque Isle County, Michigan, we trapped a number of adult Herring Gulls (Larus argentatus). The captured birds usually regurgitated while being handled. Many alewife (Alosa pseudoharengus) were found, and during the week of June 23-29, 1963, two adults regurgitated freshly eaten sea lamprey (Petromyzon marinus). A young Herring Gull, approximatley one-half grown, also regurgitated part of a sea lamprey after being captured. The expelled lampreys were evidently fresh when eaten, since they did not have the translucent appearance of spoiled ones observed elsewhere by Southern. Neither of us observed dead lampreys along the beaches of Lakes Michigan, Huron, or Superior during our summer’s work. To our knowledge there is not mention in the literature of gulls feeding on lamprey; therefore, our observation may indicate that gulls have recently begun to serve as a natural predator on this apparently introduced species.