An ArcGIS shapefile layer showing the extent of all extant and relic Adélie penguin (Pygoscelis adeliae) colonies on Shirley Island, Windmill Islands, February 2006. The field &Status& describes each polygon as extant, relic or maximum. Extant refers to the area used by breeding birds in the summer 2005/06. Maximum refers to the historic maximal extent of the colony. Relic refers to any ... colony which was not occupied by any breeding pairs during 2005/06.
Positional accuracy is approx. 1-2 m, after accounting for dGPS errors and errors in identification of the boundaries of colonies. Mapping was conducted after the end of the breeding season, so boundaries were identified as the extent of nest pebbles/fresh faeces, and it was considered that they could be reliably identified to within 0.5m.
Data were acquired using a Trimble Pro XH differential GPS. This work was completed as part of ASAC project 1219 (ASAC_1219).
Work on this project also utilised a Digital Elevation Model (DEM) created for Shirley Island. See the metadata record, &A digital elevation model (DEM) and orthophoto of Shirley Island, Windmill Islands, Antarctica& for more information (linked below).