ASSOC PROF STEPHEN WING
A cockle is a bivalve mollusc. The molluscs are things like snails and mussels, and even octopus are a type of mollusc. But bivalve molluscs have, as the name says, they have two valves – bi is two, mollusc is the shell. And so things like clams and mussels are bivalve molluscs. They are very, very common in inlets and estuaries all around the country, and people assume that they will always be there doing their job for the estuaries.