Response of the small mammal community to changes in western French agricultural landscapes.

International audienceWe studied the response of the small mammal community (rodents and shrews) to recent changes in agriculturalsystems of western French landscapes. Work was conducted on twelve sites representative of the diversity offarming systems in this region. The characteristics of small mammal assemblages in each site were assessed usingBarn Owl (Tyto alba) pellet analysis. Relationships between small mammal data and landscape descriptors wereperformed through co-inertia analysis. Richness and specific composition of the small mammal community werenot affected by the degree of cultivation but variations in species frequency could be observed. The prevalence ofsome species allowed us to distinguish three main assemblages which were characteristic of low, medium, and highintensified landscapes. Status and life traits of these species showed that intensification of agriculture has negativeeffects on density of rare and habitat-specialist species while it favours habitat-generalist species, some of thembeing known to exhibit fluctuating density. The two main ways of agricultural intensification (maize vs. other crops)did not show any significant relationships with species assemblages. Our results gave us the opportunity to suggestrecommendations on agronomical and conservation problems that may arise from these changes of agriculture inwestern France