arvicola riparius

Vole \Vole\, n. (Zool.)
   Any one of numerous species of micelike rodents belonging to
   {Arvicola} and allied genera of the subfamily {Arvicolinae}.
   They have a thick head, short ears, and a short hairy tail.
   [1913 Webster]

   Note: The water vole, or water rat, of Europe ({Arvicola
         amphibius}) is a common large aquatic species. The
         short-tailed field vole ({Arvicola agrestis}) of
         Northern and Central Europe, and Asia, the Southern
         field vole ({Arvicola arvalis}), and the Siberian root
         vole ({Arvicola oeconomus}), are important European
         species. The common species of the Eastern United
         States ({Arvicola riparius}) (called also {meadow
         mouse}) and the prairie mouse ({Arvicola austerus}) are
         abundant, and often injurious to vegetation. Other
         species are found in Canada.
         [1913 Webster]