Small mammal populations were studied during a 10 year multi-annual fluctuation of vole populations in marshes and adjacent grassland of the basin in the Jura mountains, France. Nine species were monitored: Microtus agrestis, Clethrionomys glareolus, Apodemus flavicollis, Sorex araneus/coronatus, Neomys fodiens, Crocidura leucodon, Mustela nivalis in marshes and Arvicola terrestris and Microtus arvalis in grassland, using live-trapping and index methods during July from 1993 to 2002. Populations of A. terrestris, M. arvalis, M. agrestis, S. araneus/coronatus and M. nivalis exhibited a relatively strong inter-specific temporal synchrony in their multi-annual fluctuations. C. glareolus population fluctuations were not synchronous to the Arvicola/Microtus/Sorex group, and were closer to those of Apodemus flavicollis, Neomys and Crocidura. Those results are discussed in the light of earlier studies carried out in the same region and in northern ecosystems