Until 1970, this species was only known in Minnesota on the basis of one specimen collected near Ely. From then to 1981 field researchers found it at 8 more locations in Cook County. Subsequently, Science Museum biologists added more than 60 locations. Radio tracking of individuals with small collar transmitters to trace their movements helped determine home range and territory sizes and their affinity to habitat types and that this vole species does not show regular high and low (boom or bust) cycles typical of other voles. These findings allowed the delisting of the Rock vole as a species of special concern in Minnesota.

I submit this specimen as one of special interest after having worked on field studies of the species for 10 years in Northeastern Minnesota involving intensive night and day efforts which extended the known range of the species into Lake County and Voyageurs National Park.