Corn-Fed Dead Zone in the Gulf of Mexico

At the mouth of the Mississippi River, scientist say there's a dead zone where marine life is deprived of oxygen. Researchers, who have been measuring the are in the Gulf of Mexico for two decades, say the dead zone is now 8500 square miles, bigger than ever and larger than the state of Massachusetts. Partly a natural phenomenon, its massive size is due to human activities that could be modified, says Nancy Rabalais, executive director of the Louisiana Universities Marine Consortium.