30.5 - 34 cm. 100 g. Bill long, slightly thin, black. Body plumage blackish gray. Wings dark, relatively short. Tail blackish, wedge-shaped. Legs short, black. Individuals first summer (March-August): Crown and forehead white. Feathers that cover the wings above, buff. Adult individuals: Crown and forehead white. Nape grayish. Feathers that cover the wings above, dark-brown. Males and females are similar. Juveniles are similar to individuals of first summer, but the feathers that cover de wings above are grayish.