Other Names: none
Distribution: Pacific coasts of California and Mexico.
Size: 34-36 cm in length with an 80-85 cm wingspan.
Plumage: Mostly black above and white below, with wing undersides that are white in the middle with a black border dark cap extends below the eye. The flanks and breast are black, fading into the white underside. The contrasting black and white pattern is characteristic of the species. The beak is black with a white base.