Once upon a time, Atlantic cod ran so thick in the icy waters off the coast of Newfoundland that explorer John Cabot was able to catch the fish by hanging wicker baskets over the side of his ship. More than 400 years after Cabot first visited the remote northeastern corner of North America, Newfoundland’s waters were still ripe with cod. Today, the fish are gone. Gargantuan factory trawlers started to strip-mine the seas in the 1950s; only decades later, the Canadian government was forced to close what had once been the world’s greatest fishery for lack of fish. The trawlers may have made it impossible for the species to fully recover.