This data package presents legacy data collected during 1985-1987 at Izembek Lagoon on the western end of the Alaska Peninsula. The data were collected in support of a multi-year study focused on aircraft disturbance of waterfowl, particularly Black Brant, Emperor Geese, and Cackling Geese. The study was conducted at Izembek Lagoon and included several study sites within the lagoon: Halfway Point, Grant Point, Outer Marker, Quarter Point, Applegate Cove, Norma Bay, Round Island, and Banding Island. The primary objectives were to 1) define the time periods that are most important for geese, 2) determine if certian portions of Izembek Lagoon are more important than other areas, 3) evaluate factors that influence distribution of geese within Izembek Lagoon, and 4) compare use by geese of Izembek Lagoon with use of other adjacent lagoons to determine relative importance. The raw data are provided in a .CSV format, however, PDF digital scans of original field data sheets, tables, figures, and maps are also available upon request.