Even generalist and resilient species are affected by anthropic disturbance: evidence from wild boar activity patterns in a Mediterranean landscape

Abstract

Humans have negatively impacted most ecosystems on Earth, altering how species use habitats and resources available to them, but also their circadian rhythms. Among many factors affecting animal activity patterns, conversion of native habitat into production forests and hunting are critical, and their impacts may be exacerbated by seasonal weather conditions. Both these factors are issues in Mediterranean Europe, especially in Portugal. Nevertheless, their impact on native species behavior remains largely unknown, even for generalist species often resilient to human disturbance such as wild boar (Sus scrofa). Therefore, we assessed temporal activity patterns of wild boar in Portugal to explore differences between habitats (native forest versus Eucalyptus plantations), hunting and non-hunting periods, or between seasons. We found that wild boars were primarily nocturnal, with greater nighttime activity more evident during the dry season and within plantations. Furthermore, they appeared to avoid dusk during the hunting season. Together, these patterns indicate that even a species typically resilient to disturbance and environmental change, such as wild boar, tends to avoid adverse weather conditions and disturbance factors, namely high daytime temperatures in summer and probability of encountering forestry workers or hunters. Accordingly, other more sensitive or resource-demanding mammals may also be affected, so evaluating the impacts of the studied anthropic drivers on other mammals should be prioritized to provide information for sustainable plantation management and hunting.