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South Island robins (Petroica australis australis) have frontal spots of white feathers which can be moved independently of other contour plumage to produce sudden visual contrasts. There are differences in the degree to which either the spot or the crown feathers are displayed. Display of the spot is most often interspecific or given by a lone bird, whereas raising the crown feathers usually occurs in intraspecific contexts. Details of each display are described. Crown elevation seems to function as an advertisement of aggressive levels to other robins, and, therefore, its function seems to me more specific than described for other passerines. Display of the spot is seen in response to several threatening or alarming situations, showing some of the characteristics of display of the crown or crest in other passerines. Its function in advertisement of escape or submissive motivation is clear in most intraspecific contexts, but outwardly, display of the spot in interspecific context shows strong aggressive elements. Display of the frontal spot is discussed in relation to function and evolution in other Petroica species.