The designation "Dolphin Safe" on canned tuna has become a familiar one on every supermarket shelf, and it's essential to a tuna brand's success. But the "Dolphin Safe" fishing method that's most widely used today ends up killing far more other fish and sharks than the dolphins it saves. Is saving a relatively small number of dolphins (not a currently threatened species) worth the loss of more vulnerable aquatic species? And is tuna fishing itself sustainable, anyway?

Guests:

David Shiffman, Masters in Marine Biology candidate at the College of Charleston in South Carolina and co-author of the marine biology blog SouthernFriedScience

Mark Palmer, Associate Director of the International Marine Mammal Project at the Earth Island Institute