Purple butterflies on a surf beach
I was fortunate to spend a few days at Noosa over the Easter break and by chance I had my camera on me when a pair of oystercatchers worked the ebbing tide. If you have ever tried to catch pipis, a bivalve mollusc located on the waterline of the surf, you will realise how difficult this task can be. Incredibly oystercatchers are able to work the breaking wave zone and locate and pull pipis out of the sand with regular monotony.
Of course finding pipis is one thing but being able to crack them open is another matter altogether, especially if you are a bird. Again these birds appear to find the task relatively easy. They insert their bill into the hapless bivalve and carry them to the beach, where they insert their beak further into the shell and then using mandibles like a knife they slice through the strong muscle of the mollusc before extracting them completely from their shells. And in no time at all they are feeding on a nutritious piece of protein, thanks to their fishing skills and well-equipped bills.
And left on the beach are the two valves of the former pipi! Just minutes ago it was buried in the sand beneath the waves and now the only evidence of its existence is that familiar purple butterfly-like pair of valves.