Behavioural responses to temporal variations of human presence: Insights from an urban adapter

Human-dominated environments are growing worldwide, forcing animals to adapt to new conditions characterized by increased risks and/or anthropogenic resources availability. While numerous studies have compared behavioural patterns of rural and urban populations, little is known about plastic behavioural responses to temporal variations in human presence. We modelled the behaviour-specific resource selection of 15 wild boars (Sus scrofa) GPS-tracked between 2017 and 2019 in a tourist area in Italy characterized by high seasonal variability of human presence. By means of activity sensor data, we differentiated between two behavioural states with different ecological needs: resting (safe shelter) and activity (food intake). We investigated the variability of selection/avoidance of infrastructures and beaches, across seasons and behavioural states. We expected human-built landscape features to be avoided for resting and selected for activity, with a strength proportional to the seasonal level of human presence. Instead, wild boars selected locations near infrastructures and away from beaches, both for resting and while being active. We showed that the similarity of behavioural patterns exhibited during the resting and active phases was accountable to the wild boar activities being spatially constrained by the proximity with their previous resting location. As expected, the selection for infrastructure proximity and avoidance of beaches peaked in summer (maximum human presence) and was negligible in winter (least human presence), showing that a variable human presence elicits intra-individual plastic responses in animal populations. Our results suggest the behavioural flexibility of wild boars as a key factor enabling them to rapidly colonize human-dominated environments.