Predation of Pelecypods and Gastropods by Fasciolaria Hunteria (Perry)

Laboratory and field predation of pelecypods and gastropods by Fasciolaria hunteria are described. Fasciolaria opens pelecypods by wedging its shell between the valves. Small gastropods are enveloped by the foot, while larger gastropods are eaten while the predator's foot holds out the operculum. A variety of pelecypods are eaten, oysters being the most attractive. Five gastropod species were eaten, including the oyster drill. Oyster drills are more attractive to Fasciolaria than are oysters, rates of daily predation of drills, in the presence of oysters, being as high as 5.7 drills/Fasciolaria. Fasciolaria are found concentrated on oyster areas where drills or oysters probably form a major part of their diet.