Photos: BP oil spill residue found on pelicans in Minn.

Carrying equipment
Mark Clark, an ecologist and faculty member with North Dakota State University's biological sciences department, carries equipment to a boat on Minnesota's Marsh Lake on Wednesday, May 9, 2012. The lake is home to a colony of American white pelicans. Researchers are trying to determine whether pelicans carry residue from the 2010 oil spill in the Gulf of Mexico.
Ann Arbor Miller for MPR) ( Read the story