Fish remains recovered from archaeological sites along the California coast to the immediate north and south of Pt. Conception in San Luis Obispo and Santa Barbara counties are used to test the hypothesis that the ranges of marine fishes have remained constant during the Holocene. The archaeological record shows that as many as 16 species are only found in locations south of Pt. Conception and as many as eight are found only to the north. These prehistoric ranges are consistent with their present ranges.