When the waters of the Chesapeake Bay warm up in late April and early May, blue crabs crawl out of the mud where they've spent the winter and, having grown too big for their shells, promptly begin to molt. Fishermen who catch them at this crucial juncture put the crabs in tanks in order to monitor the molting process; when the crabs have completely shed their hard outer shells, they are shipped to market wearing only a thin, edible covering and still very much alive. Once they reach their destination they should be consumed within four days, before they begin to rebuild their hard shells.
Softshell crabs come from other areas, too, including the Carolinas, Louisiana, Georgia, and Florida. In the Gulf of Mexico, the season begins in early April and lasts through October or November. The season is shorter in the Chesapeake, lasting only until July.
Softshell crabs are best prepared simply—battered and deep-fried or pan-fried with lemon and butter. Nestled between two slices of soft white bread along with bibb lettuce and a dab of tartar sauce—a classic Maryland-style preparation—they make for a delicious and succulent sandwich.