Small bouyant tern. Breeding adult has distinctive dark smoky gray body and contrasting white cheeks (can look like broad white "whiskers" in flight). Nonbreeding plumage pale silvery gray overall; juvenile has dark-checkered back. Note rather stout bill (albeit thinner than Gull-billed Tern); compare to Common and Arctic Terns and square tail. Feeds by picking from surface, not splash-diving like typical terns.