Logging and livestock influence the abundance of common mammal species in Mediterranean forested environments

Abstract

Forest and livestock management puts pressure on forests and the wildlife they support. Although many species may be negatively affected by these human activities, the abundance of other species may be promoted, although this has perhaps received less attention in livestock, logging, and conservation management plans. Wild boar and red fox, two common mammals distributed throughout Europe, occupy a wide variety of Mediterranean environments. Little is known about how increases in logging and livestock management have changed their status. This work models the response of wild boar and red fox to these pressures in the human-altered Mediterranean forest landscapes of the central Iberian Peninsula (NHR), where the predominant land uses in the last hundred years have focused on livestock and logging (thinning and selective cutting). We collapsed land use and habitat structure variables into independent habitat vectors using principle component analysis (PCA) and then used a general linear model (GLM) to explain the relationships between red fox and wild boar abundance and the independent habitat vectors observed in human-altered forests. Livestock and logging activity was positively correlated with wild boar abundance, and negatively correlated with red fox abundance, although red fox tolerated open scrubland that had been logged. Red fox abundance remained negatively correlated with the same variables when boar abundance was added as an environmental predictor in the model, but some additional variance was explained, demonstrating the need to include indirect interspecific relationships in the habitat-species models. The combined effects of wild boar, logging and livestock are indirectly important factors which modify habitat structure and negatively affect red fox. Therefore, common mammal species are influenced by livestock and logging in different ways which necessarily may be taken into account in management and conservation decisions in Mediterranean human-altered forests.