Crabs of future past

Arguably the most iconic species of the Chesapeake Bay - one of North America's largest estuaries -- is the blue crab (Callinectes sapidus). A Chesapeake Bay Stock Assessment Committee report (http://bit.ly/1E13Z0f) estimated that almost 300 million of these crustaceans inhabited the region in 2013; during that same year, Bay-wide combined commercial and recreational landings for blue crabs totaled over 18 million kilograms. This fishery, currently the country's largest for crabs and the Bay's most economically valuable overall, is strongly regulated, in part because ofthe species' notoriously variable year-to-year abundance. So how might today's crab populations be different from those in the more distant past?