ST. PETERSBURG, Fla. (AP) - Greenpeace is launching a three-month expedition from Florida to research the impacts of the Gulf of Mexico oil spill.

The environmental group is embarking its trip Thursday in St. Petersburg. It will visit the Florida Keys and the Dry Tortugas before heading toward the site of the busted wellhead.

Greenpeace will host independent scientists researching the potential effect of oil and dispersants on bluefin tuna, blue crab larvae, sponges, and other species.