The morphology and feeding ecology of the ground croaker, Bairdiella ronchus, in a shallow bay on the south coast of Jamaica was studied. Morphological assessments revealed that the species displays positive allometric growth. Their bodies become thicker and deeper as they grow in length. Stomach content analyses were performed, and the feeding indices of the two size classes (juvenile and sub-adults) of B. ronchus were determined. Juveniles and sub-adults were shown to prefer amphipods (Hyallela sp.) Both classes consumed Sargassum and amorphous organic matter. The consumption of Sargassum, particularly by the sub-adults, is noteworthy as this species is generally considered to be a carnivore, preferring to feed on fish and crustaceans. It is likely that the species ingests Sargassum as they feed on amphipods that colonise these Sargassum blooms.