Some aspects of the foraging ecology of migrant juvenile sandpipers in the outer Bay of Fundy

Abstract

Thirty-seven sandpipers (29 semipalmated and 8 least) were collected in early September 1983 on an intertidal flat on the outer Bay of Fundy. Analysis of esophagus and gizzard contents revealed a variety of benthic invertebrates but the diets of both species were dominated by the amphipod Corophium volutator (Pallas). Females of both species ate larger Corophium than did males of the same species. Both least and semipalmated sandpipers were underutilizing a cohort of large (7–10 mm) Corophium. It is possible that the large amphipods have reached a size refuge from predation such that the energy required to handle and ingest these large prey offsets too great a portion of the energy obtained.