<p>Cod and other commercial ground fish are caught in a net in the Gulf of Maine. Our appetite for fish is wreaking havoc on aquatic populations worldwide. The conservation group World Wildlife Fund predicts that if cod fisheries continue to be fished at current rates, there will be no cod left by 2022. "Seventy-five percent of fisheries are overfished," says marine biologist Enric Sala. "If nothing changes, all fisheries will have collapsed by 2050." The solution, says Sala—a National Geographic Society fellow—is involving all levels of society, from consumers to policy makers. "The solutions exist, we just need the political will to implement them at [a] large scale," he adds.</p>