This data set contains processed survey data for the Midwinter Aerial Seabird Surveys conducted in Puget Sound area from December through February annually. This is a zipped (compressed) file geodatabase containing GIS data and must be downloaded, unzipped and viewed in using GIS software such as ArcMap or ArcGIS Pro. This includes avian observations, survey routes and surveyed areas, as well as supplemental layers involved in subsequent statistical analysis such as depth-basin analysis strata, excluded areas, species look-up and crosswalk tables, and a table of abundance estimates. An interactive web-map displaying abundance estimates derived from this data is viewable here.This geodatabase contains the following datasets: PSEMP_Analysis_Strata (polygon), Pocket_estuaries (polygon), PSEMP_Survey_Observations (point), PSEMP_SurveyRoutes (polyline), PSEMP_SurveyArea (polygon), Species (table), PSEMP_Group (table), SpeciesPSEMP_Group (table), AbundanceEstimates (table), PSEMP_LogSurvey_OverlapWithin (polygon).