ASSOC PROF STEPHEN WING
If you removed cockles from a marine food web, it would have dramatic effects on all the consumers, all of the animals that rely on their services. And we can guess that for New Zealand, but we know that from some systems where this has actually happened. And so there are several places around the world where there have been huge die-offs of bivalves – mussels, clams and so on – and this has had effects all the way up through the food web to the highest levels, to sea birds that feed on little cockles or little clams, all the way up to sharks and large fish. When you disturb a food web, at any place but particularly near the bottom, this can have sort of reciprocating effects all the way up the food web.