Home range and activity areas of foxes (Vulpes vulpes) in urban and peri-urban areas

We investigated the home range and activity areas of the red fox (Vulpes vulpes) in urban and peri-urban areas of Perth, Western Australia. Foxes were tracked via satellite GPS between December 2019 and September 2020 to evaluate spatial movement patterns. We first estimated home-range size by using area-corrected autocorrelated kernel density estimation (AKDEc) for each fox over the entire tracking period. We then used a 5-day sliding window approach with area-corrected (not autocorrelated) kernel density estimation (KDEc) to identify ‘activity areas’. We defined fox activity areas as those where a fox had similarly sized 5-day sliding window KDEc areas for 10 or more days. Some foxes had very stable home ranges, and the AKDEc area resembled the KDEc activity areas. However, some foxes shifted their activity areas throughout the tracking period, and the KDEc activity areas were variable, often smaller but occasionally larger than the AKDEc home range. Some foxes made mostly nightly forays into adjacent areas, and on some occasions these preceded an activity area shift into these areas. The AKDEc and KDEc areas often included substantial unused areas reflecting physical or biological barriers, and therefore inflated home range area sizes.