Behavioural responses to ecological stressors: sex-specific shifts in wild boar activity over the Mediterranean summer

Ecological perturbations associated with the Anthropocene are increasingly affecting animal populations. The interactions between rising temperatures, landscape features, human activities and predators can alter mammal behaviour, yet these factors are rarely examined simultaneously. Understanding how mammals respond to multiple stressors is key to improving knowledge of their behavioural flexibility and predicting shifts in interspecific and human–wildlife interactions. We investigated the effects of temperature, habitat features, human activity and predator activity on daily activity levels and nocturnality in a widespread ungulate, the wild boar, Sus scrofa . We conducted population level and sex-specific analyses of camera trap data collected in eight Mediterranean protected areas during the summers of 2021–2024 (19 306 camera-days; 208 sites). While an effect of temperature on daily activity level was not supported, wild boar increased nocturnality on warmer days, indicating a temporal redistribution of activity rather than an overall decline in activity in response to heat. Activity increased near persistent water sources and, for males, this relationship was stronger on hotter days. Activity also increased near agricultural land, which was used at night as open habitat. Wild boar activity decreased at sites with higher human visit rates. Individuals also showed predominantly nocturnal and crepuscular activity patterns, suggesting spatiotemporal avoidance of humans. However, fine-scale temporal adjustments emerged: males and females without offspring tended to show nocturnal and crepuscular activity patterns. Females with offspring showed greater diurnal activity, consistent with increased avoidance of nocturnal predators, the grey wolf, Canis lupus . These results suggest that wild boar cope with Mediterranean summers through flexible, sex-specific temporal adjustments shaped by thermal, ecological and risk-related drivers. Our study emphasizes the importance of considering multiple stressors when assessing behavioural responses to environmental variation.