The sky was white with gannets and filled with their manic chatter. Wings folded to their sides, they plummeted into the sea like feathered missiles, leaving green bubble trails in their wakes. They were hunting sardines, and the water boiled with fish. It was as if this patch of sea off the eastern coast of South Africa had been turned into a pot of bouillabaisse—and everyone was falling to the feast. Scores of circling dolphins harried the sardine shoal into an ever tightening mass. Panicked sardines threw themselves into the air and splashed back into the melee. A pale pink dorsal fin sliced through the midst. Then another. "Copper sharks!" said Mark Addison, our boat skipper. "Fantastic! Look—three, four, five