A mile off Florida's Big Pine Key and 30 feet under water, sunlight streams down onto lumps of brain coral. Scarlet grouper, white hogfish and electric-blue angelfish dart about. It seems the kind of underwater scene that made the Keys a diver's paradise, unless you know the current reality, which Ken Nedimyer does. Hovering over the bottom in scuba gear, Nedimyer buries his hand in sand and exhumes what look like small white bones but are actually dead pieces of once-ubiquitous staghorn coral. Then he makes a sweeping motion with his arm, the pantomimed message clear: There used to be a lot ... Read More