Isotopic shift for defining habitat exploitation by the Antarctic limpet Nacella concinna from rocky coastal habitats (Marian Cove, King George Island)

► δ13C and δ15N of the Nacella concinna and their potential food sources were measured. ► Our results indicate a dietary shift between habitats as well as size classes. ► Grazing by limpets can determine microalgal and/or macroalgal abundance and coverage. ► Trophic structure can change along environmental gradients in the Antarctic.