As suggested by the common name, rocks are a prominent feature in the habitat of this species. Rock Voles prefer forest habitats with moss-covered rocks and boulders, thick ground cover, and accessible water. Females are able to mate 24 hours after giving birth, so they nurse one litter while pregnant with another. They usually have 3 or 4 offspring in a litter. The period of pregnancy is 19-21 days.

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account