Several photo ‘observers’ examine images and enter data based on what they see in the imagery. The first observer, ‘PRI’ = the primary observer, looks at all photos taken and records bird presence/absence. The ‘SEC’ = the secondary observer, speciates the birds found by the primary observer, and counts the Steller’s eiders. The ‘TER’ = the tertiary observer, reviews the speciation and/or counts of the secondary observer as a check. The ‘ERR’ = the error rate observer, independently records bird presence/absence in a subset (10%) of the photos that the primary observer viewed as a check on the PRI accuracy. When all are complete, they are combined into the final data table, Combined Datasheet_STEI Overhead, that will be used for analysis.
All survey photos are analyzed by various photo analysts (See QC, below), and data from the observations are recorded in Excel spreadsheets. All photos are analyzed in a preliminary fashion first, i.e., photos are identified as having either no birds or having known or possible birds. The subset of photos that were identified as having birds or possible birds are then analyzed completely to determine the species and number of birds identified to the degree possible. The ‘PRI’ (as notated on the datasheets) or primary observer is the individual who first goes through all photos and records presence/absence of any birds and makes notes of interest to the project. The ‘SEC’ or secondary observer speciates the birds found by the primary observer, and counts the Steller’s eiders. The ‘TER’ or tertiary observer reviews the speciation and/or counts of the secondary observer if/when requested by the secondary observer. The ‘ERR’ or error rate observer independently records bird presence/absence in a subset (10%) of the photos that the primary observer viewed to assess the accuracy of the primary observer’s presence/absence determinations.
After photo analyses are completed by the analysts, additional data about the images (such as time, location, altitude, and speed of the aircraft) are taken from camera cards and Aviatrix software and added to the table in an additional 8 fields. This step adds spatial data about each image in preparation for analyses of abundance in the study area (these additional 8 fields are fields #20-27 in the table; see data dictionary for field descriptions).
