File photo shows an exhausted oil-covered brown pelican sitting in a pool of oil from the Deepwater Horizon gulf oil spill at Queen Bess Island Pelican Rookery

 
File photo shows an exhausted oil-covered brown pelican sitting in a pool of oil from the Deepwater Horizon gulf oil spill at Queen Bess Island Pelican Rookery
An exhausted oil-covered brown pelican sits in a pool of oil from the Deepwater Horizon gulf oil spill at Queen Bess Island Pelican Rookery, 3 miles (4.8 km) northeast of Grand Isle, Louisiana in this June 5, 2010 file photo. When BP's Deepwater Horizon oil rig exploded and sank in the Gulf of Mexico last April, killing 11 workers, authorities first reported that no crude was leaking into the ocean. They were wrong. One year on, oil from the largest spill in U.S. history clogs wetlands, pollutes the ocean and endangers wildlife, not to mention the toll it has inflicted on the coastal economies of Florida, Mississippi, Alabama and especially Louisiana. REUTERS/Sean Gardner/Files (UNITED STATES - Tags: ANIMALS ANNIVERSARY BUSINESS DISASTER ENERGY ENVIRONMENT)