TROPHIC ECOLOGY OF THE INTERTIDAL SEA-ANEMONES PHYMACTIS-CLEMATIS DANA, 1849, AULACTINIA-MARPLATENSIS (ZAMPONI, 1977) AND AULACTINIA-REYNAUDI (MILNE-EDWARDS, 1857) (ACTINIARIA, ACTINIIDAE) - RELATIONSHIPS BETWEEN SEA-ANEMONES AND THEIR PREY

The feeding ecology of the intertidal sea anemones Phymactis clematis Dana, 1849, Aulactinia marplatensis (Zamponi, 1977) and A. reynaudi (M ilne-Edwards, 1857) (Actiniaria: Actiniidae) from Punta Cantera and Sa nta Clara del Mar (Argentina) was studied using the following relation s: available and ingested food, prey and predator size, and prey and p redator weight. The food ingested by the three sea anemones clearly re flects the available food, both in quantitative and qualitative terms. In both locations, no correlation was observed between sea anemone si ze and prey size, or between predator weight and prey weight. These fa cts suggest that sea anemones feed principally on prey detached by wav e action; the mussel Brachydontes rodriguezi d'Orbigny, 1846 is the pr incipal prey in the study areas.