Gulf residents track washed up gunk, MSNBC, January 3, 2010:
Shirley Tillman... is not alone in her belief that nighttime air traffic over the gulf is due to dispersant spraying by C-130 aircraft, which also were used during the initial response.
“The air traffic is constant,” she said. Her theory: “Spotter planes go out during the day, write down the problem spots are. … Then you can sit on the beach at night and watch (C-130s) going back and forth.”