i can't take these in today, turn everything around and give you answers tomorrow. >> reporter: they are collecting evidence and building a legal case against bp, looking for a settlement big enough to rebuild the gulf. >> this is not a spill about turtles or shorelines or about fish. this is a spill about an ecosystem. >> reporter: one year later, man and machine work to clean marshes still covered in oil. >> everything out there is getting some of that sheen. you can't see it, still, and it's been happening for a year. you can't see any of it. all of those birds, even if all they have is a little smudge on their breast, they're constantly trying to clean that off. they're ingesting the oil. >> reporter: last year, over 2,000 birds were rescued from oil, with over 1,200 moved away from the spill to texas and florida.