GRAZING BY THE ANTARCTIC FISH NOTOTHENIA CORIICEPS - EVIDENCE FOR SELECTIVE FEEDING ON MACROALGAE

In Potter Cove, King George Island, Antarctica, macroalgae provide a s ignificant food resource for herbivores. The demersal fish Notothenia coriiceps feeds on macroalgae. Eighteen algal species were identified in stomach contents: two chlorophytes, ten rhodophytes and six phaeoph ytes. Among these the rhodophyte Palmaria decipiens, the phaeophyte De smarestia menziesii and the chlorophyte Monostroma hariotii comprised the greatest proportions of algal biomass. A food selection study show ed four algae to be preferred (P. decipiens, M. hariotii, D. menziesii , Iridaea cordata) and two species to be avoided (Desmarestia anceps a nd Himantothallus grandifolius) by N. coriiceps. The present investiga tion indicates that this fish feeds not only intentionally, but also s electively, on macroalgae. Preference for particular algal species is not related to associated epifaunal biomass or to associated amphipod biomass.