GPS tracking and data preparation

GPS collars were programmed to take position fixes in bursts of 20 (15 second inter-fix interval), with an inter-burst interval of 10–20 minutes. The inter-burst interval increased to 60 minutes once the battery had lost approximately 60% of its original charge. Positions were transmitted immediately after collection via GSM network to an internet server, from which they were downloaded for processing and analysis. To minimize the potential initial effects of capture and handing on movement and behavior, we excluded positions collected during the first day after each fox was released. Furthermore, since we were interested in position data collected during movement/travel, we removed those portions from the data that indicated stationary or localized behavior, e.g., time in dens and day beds or time spent investigating focal points. For each burst, we calculated sinuosity^42,43 and average movement speed between consecutive positions. We then excluded all bursts with sinuosity >0.5 and average movement speed <0.1 m/s. Data preparation and subsequent analyses were conducted using R version 3.5.1⁴⁴.