This multi-layer GeoPackage contains the Alaska Arctic Coastal Plain Aerial Breeding Pair Survey design transects from 2007 to present. The original transects were created as shapefiles and imported to this SQLite database. Transects were saved as individual polylines named according to the year they were created (e.g., “main.ACP_2007_Trans,” “main.ACP_2008_Trans,” “main.ACP_2009_Trans,” etc.). These aerial transects were developed systematically from randomly-selected start points and created along constant lines of latitude. The inter-transect spacing in the low, medium, high, and very-high density strata varies so that areas with higher waterfowl density are surveyed more intensively. The current four-year rotating panel design was developed in 2007 based on aerial survey data collected during the North Slope Eider Survey from 1992 to 2006.
Additional Information:DESIGN TRANSECTS (Design_Files/Design_Transects/ACP_YYYY_Transects.shp)- Design transect locations and lengths should be treated as a general guide to survey design and not an accurate measure of survey effort or plane location in any given year.DESIGN STRATA (Design_Files/Design_Strata/ACP_YYYYtoYYYY_DesignStrata.shp)- This is a polygon .shp layer where the STRAT and STRATNAME fields correspond with sampling intensity (variation in transect spacing).- AREA and LENGTH fields should be checked or recalculated since they are of unknown origin and precision.
