Females are usually larger than males.
It wings and back are blue-gray and its underparts are white with fine black barring. The undertail coverts are white and fluffy, and quite noticeable in the field. The top of its head, called the crown, is dark and separated from the blue-gray back by a white eyebrow that flares behind its deep red eye. Its sharp talons and curved bill are excellent tools for holding prey and tearing flesh. It has broad, stocky wings and a long tail.