| Summary: | Progress Code: completed Statement: Data were acquired with a Garmin 26 GPS receiver, the accuracy of which is better than an average handheld GPS model, such as the Garmin 12. In order not to overestimate the quality of the data, it is sensible to assume that nest locations were acquired with an uncertainty between 5 and 10 m. Very little information is known about the distribution and abundance of snow petrels at the regional scale. This dataset contains locations of bird nests, mostly snow petrels, mapped in the Windmill Islands during the 2002-2003 season. Location of nests were recorded with handheld GPS receivers connected to a pocket PC and stored as a shapefile using Arcpad (ESRI software). Descriptive information relating to each bird nest was recorded and a detailed description of data fields is provided in the detailed description of the shapefiles. Two observers conducted the surveys using distinct methodologies, Frederique Olivier (FO) and Drew Lee (DL). Three separate nest location files (ArcView point shapefiles) were produced and correspond to each of the survey methodologies used. Methodology 1 was the use of 200*200 m grid squares in which exhaustive searches were conducted (FO). Methodology 2 was the use of 2 transects within each the 200*200 m grid squares; methodology 3 was the use of 4 small quadrats (ca 25 m) located within the 200*200m grid squares (DL). Nests mapped in a non-systematic manner (not following a specific methodology) are clearly identified within each dataset. Datasets were kept separate due to the uncertainties caused by GPS errors (the same nest may have different locations due to GPS error). Three separate shapefiles describe survey methodologies: - one polygon shapefile locates the 200*200 grid sites searched systematically (FO) - one polygon shapefile locates the small quadrats (DL) - one line shapefile locates line transects (DL) Spatial characteristics, date of survey, search effort, number of nests found and other parameters are recorded for the grid sites, ...
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