''Austrovenus stutchburyi'', common name the New Zealand cockle or New Zealand little neck clam, is an edible saltwater

clam Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two shel ...

, a marine bivalve mollusc in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Veneridae The Veneridae or venerids, common name: Venus clams, are a very large family of minute to large, saltwater clams, marine bivalve molluscs. Over 500 living species of venerid bivalves are known, most of which are edible, and many of which are ex ...

, the Venus clams. Its Māori name is (North Island) or (South Island).

Habitat

Cockles live in harbours and estuaries in New Zealand. They live in the subtidal to intertidal zone, and when they are in the intertidal zone they live between the low tide mark and the mid tide mark. Cockles are unable to survive above the mid tide mark because of the increased exposure time. Cockles prefer to live in soft mud and fine sand, however they can be suffocated by extremely fine sand. For this reason, they mainly live in areas with a large grain size. The cockles bury 2 to 3 cm under the sand.

Body

Cockles have a soft body which is protected from predation, desiccation and wave movement by a sturdy shell. Predators find it difficult to pierce the shell of adult cockles. Sea birds drop cockles from high up, smashing their shells, to eat the body, but fish (such as flounder) can't break the shells. Younger cockles are more vulnerable to predation because their shells aren't as hard as adult cockles. If a cockle lives in the intertidal zone it is protected against desiccation by the shell closing tightly together (the adductor muscles do this). A small amount of water is stored inside the shell, keeping the cockles body moist. Strong wave action can dislodge cockles. The shell prevents damage to the body when it is drifting around in the water.

References

* Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 * Glen Pownall, ''New Zealand Shells and Shellfish'', Seven Seas Publishing Pty Ltd, Wellington, New Zealand 1979

{{Taxonbar, from=Q3014371 Veneridae Bivalves of New Zealand Bivalves described in 1828 New Zealand seafood

Habitat

Body

See also

References