An enquiry into the changing status of the Water Vole Arvicola terrestris in Britain

Abstract

ABSTRACTAn enquiry was conducted into the changing status of the Water Vole Arvicola terrestris in Britain using an analysis of the data contained in County Mammal Reports. These were supplemented by a questionnaire survey and site descriptions from the Waterways Bird Survey organized by the British Trust for Ornithology. There was close conformity between the results obtained from these differing sources. There are indications that the Water Vole population has suffered a long‐term decline this century, possibly due to adverse habitat changes. Pollution of rivers in the 1950s by organochlorine insecticides, compounded in the 1960s and ′70s by the spread of the introduced American Mink Mustela vison have apparendy exacerbated the situation in recent years. All sources agreed that predation by Mink was considered to be the most important single threat to the Water Vole population. An objective survey is required to form the basis for a conservation plan and future monitoring of the Water Vole's status.