baitfish

[ beyt-fish ]
/ ˈbeɪtˌfɪʃ /

noun, plural (especially collectively) bait·fish, (especially referring to two or more kinds or species) bait·fish·es.

a small fish that is a source of food for a larger fish: Fishermen knew the presence of baitfish meant plenty of bass nearby.
Angling. any small fish, as a minnow or shiner, used as bait.

Origin of baitfish