Dan Rodricks: For a renewed Chesapeake Bay, in oysters we trust

My favorite facts about the Chesapeake Bay involve oysters: They were once so plentiful they could filter all bay waters (estimated at 19 trillion gallons) in less than a week; oyster reefs were once so large they constituted navigational hazards; and the competition for oysters was so fierce and violent in the 19th century that the Maryland legislature established an Oyster Navy to keep tongers and dredgers from killing each other. (Photo: Baltimore Sun)