Molluscivore

A molluscivore is a carnivorous animal that specialises in feeding on molluscs such as snails, bivalves, brachiopods and cephalopods. Known molluscivores include numerous predatory (and often cannibalistic) molluscs, (e.g.octopuses, murexes, decollate snails and oyster drills), arthropods such as crabs and firefly larvae, and, vertebrates such as fish, birds and mammals. Molluscivory is performed in a variety ways with some animals highly adapted to this method of feeding behaviour. A similar behaviour, durophagy, describes the feeding of animals that consume hard-shelled or exoskeleton bearing organisms, such as corals, shelled molluscs, or crabs.

Molluscivory is performed in several ways.

In some cases, the mollusc prey are simply swallowed entire, including the shell, whereupon the prey is killed through suffocation and or exposure to digestive enzymes. Only cannibalistic sea slugs, snail-eating cone shells of the taxon Coninae, and some sea anemones use this method.

One method, used especially by vertebrate molluscivores, is to break the shell, either by exerting force on the shell until it breaks, often by biting the shell, like with oyster crackers, mosasaurs, and placodonts, or hammering at the shell, e.g. oystercatchers and crabs, or by simply dashing the mollusc on a rock (e.g. song thrushes, gulls, and sea otters).

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