Changes in agricultural systems from 1956 to 2010 and shifts in patterns of Arvicola terrestris outbreaks: comparing trends in Burgundy, Franche-Comté, and the Alps
Changements agricoles de 1956 à 2010 et évolution des pullulations d’Arvicola terrestris: comparaison entre la Bourgogne, la Franche-Comté et les Alpes
Résumé
Since the mid-20th century, farming and livestock systems have undergone a series of modifications, which have led to changes in how farmlands
are used and in landscape composition. This study examined whether a link exists between these long-term changes and the occurrence of water
vole outbreaks in certain regions of France. A comparison of the patterns observed in 7different regions was carried out using town-level data
obtained during the French Census of Agriculture; these regions are located in eastern France (Burgundy, the Jura, and the Alps) and are associated
with different mountain ranges. Although the baseline values of land use descriptors (e.g., ratio of land under permanent grass to usable farm area,
ratio of land under permanent grass to total land under grass, and stocking rate) were found to vary across regions, the occurrence of water vole
outbreaks was always associated with grasslands being stocked at moderate rates. Land use and landscape composition patterns were similar for
study regions in the Doubs and Burgundy that experience water vole outbreaks; they differed for natural reserves in the Alps.
Une comparaison a été menée entre territoires de divers massifs montagneux de l’est de la France (Alpes, Bourgogne, Jura) en utilisant,
avec quelques précautions, les données communales du Recensement Général de l’Agriculture. Si les valeurs de seuil (STH/SAU,
STH/Surface en herbe, chargement...) diffèrent d’une zone à l’autre, la présence de pullulation est toujours associée à des espaces
essentiellement herbagers utilisés à des chargements modérés. Les trajectoires sont assez semblables entre les territoires du Doubs et
de Bourgogne concernés par les pullulations mais diffèrent avec celles des zones alpines.