Caprellid amphipods: fast food for the reproductively active

Abstract

Caprellid amphipod abundance within seagrass meadows of Padilla Bay, Washington, USA, reaches >93 specimens · 625 cm −2 during winter. When shiner perch Cymatogaster aggregata Gibbon invade the seagrass on reproductive migrations, caprellid abundances drop to <2 specimens · 625 cm −2. Although caprellids normally do not constitute a major item in fish diets, shiner perch preferentially preyed upon the caprellids immediately following immigration into the grassbeds. This “critical window” of predation previously has not been reported.