One of four very similar terns on this continent. The species lives up to its name as a “common” tern mainly in the northeast; over much of the continent, it is outnumbered by the similar Forster’s Tern. Forages mostly by flying over water, hovering, and plunging to catch prey below surface. Sometimes dips down to take items from surface of water, or pursues flying insects in the air. Occasionally steals food from other terns.