Aerial surveys associated with Deepwater Horizon Bird Study #2 occurred during the summer of 2010 and the winter of 2011. Data collection efforts were led by R.G. Ford Consulting Company, on behalf of the U.S. Fish and Wildlife Service. To conduct the surveys, study personnel flew in airplanes over the spill affected area and documented all observed wildlife along transects including both avian and non-avian species. Although not a goal of the study, some data on the presence of oil and the presence of sargassum were collected as well. Four types of aerial surveys were conducted: 1) marine surveys flown in a north-south direction; 2) outer coast surveys flown along the shoreline; 3) barrier island surveys, which are similar to outer coast surveys but were flown along either side of barrier islands; and 4) nearshore surveys that were flown in a zigzag line pattern between the mainland and the barrier islands. Observations were recorded as audio files and later tabulated into separate observer-specific spreadsheets; associated GPS data were also recorded by the plane’s navigation software. The goal of these efforts was to collect data that would facilitate the development of an estimate of avian abundance in the northern Gulf of Mexico.