ECOLOGICAL AND BEHAVIOURAL CONSIDERATIONS RELATED TO THE FEEDING OF CONCHOLEPAS CONCHOLEPAS (MOLLUSCA : GASTROPODA : MURICIDAE)

Abstract

The muricid Concholepas concholepas (Bruguicre), known in Chile as loco, is currently one of the country most valuable mollusc. The present work is a first attempt to understand the feedingbehaviour and the basic facts about the life history of the species. Within the post-capsular life history of C. concholepas it is possible to recognize 4 stages: 1) pelagic larvae, 2) settlement and juvenils, 3) advanced juvenils and intertidal adults, 4) subtidal adults. The main prey item for each of the benthic stages are presented. The feeding behaviour of C. concholepas is described for the first time. A peculiar satiation-aimed feeding strategy, with active and
inactive feeding periods, is described. The food, barnacles and bivalves, consumed by C. concholepas during active periods of feeding amounted for 4.60 - 5,68°/o of loco’s body weight per day. Ifextensive periods of time (active and inactive feeding periods) are computed, the percentage decreases 10 to 20 times. Laboratory experiments showed that different sizes of locos selected the prey size, Perumytilus purpuratus (Lamarck), consumed. Six different behavioural mechanisms in the obtainment and ingestión of preysby locos are described: 1) buldozing and suction, 2) mechanical action and suction, 3) enveloping, opening and suction, 4) enveloping and suction, 5 )boring and suction and 6) smashingand suction.