Fig. 2

Conceptual framework to identify nesting attempts using GPS and ODBA data. Window limits for each sex were estimated by comparing average daily ODBA patterns between incubation and non-incubation periods. We calculated threshold values from the AvODBA values on incubation and non-incubation days, as well as the position error of each tag on incubation days. Days with AvODBA and/or IWDD values lower than the thresholds were labelled as possible incubation days. Nesting attempts were identified when AvODBA and/or IWDD values fell below the thresholds for a minimum of 2–3 consecutive days