Response of the small mammal community to changes in western French agricultural landscapes.
Résumé
We studied the response of the small mammal community (rodents and shrews) to recent changes in agricultural
systems of western French landscapes. Work was conducted on twelve sites representative of the diversity of
farming systems in this region. The characteristics of small mammal assemblages in each site were assessed using
Barn Owl (Tyto alba) pellet analysis. Relationships between small mammal data and landscape descriptors were
performed through co-inertia analysis. Richness and specific composition of the small mammal community were
not affected by the degree of cultivation but variations in species frequency could be observed. The prevalence of
some species allowed us to distinguish three main assemblages which were characteristic of low, medium, and high
intensified landscapes. Status and life traits of these species showed that intensification of agriculture has negative
effects on density of rare and habitat-specialist species while it favours habitat-generalist species, some of them
being 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 suggest
recommendations on agronomical and conservation problems that may arise from these changes of agriculture in
western France.