MEPS 240:291-295 (2002)  -  doi:10.3354/meps240291

ABSTRACT: The aim of this study was to investigate, by use of δ¹³C and δ¹⁵N, the diet of co-occurring intertidal molluscs species within a community dominated by the oyster Crassostrea gigas and its epibiont, the common Atlantic slipper limpet Crepidula fornicata. The results showed that the δ¹³C versus δ¹⁵N values of C. gigas differed from those of the deposit feeders considered but also from the other suspension-feeding molluscs (i.e. Mytilus edulis, Cerastoderma edule and C. fornicata), being more depleted in ¹³C and in ¹⁵N. The results suggest more similarities in the assimilated food sources of C. fornicata, C. edule and M. edulis. In particular, the δ¹³C and δ¹⁵N differences between C. gigas and C. fornicata suggest that these associated suspension feeders in many shellfish culture areas may not necessarily be competitors for food sources when food is not limited.

KEY WORDS: Benthic food web · δ¹³C · δ¹⁵N · Molluscs · Crassostrea gigas · Crepidula fornicata · Oosterschelde