Redbacked Vole or Field-mouse (Evotomys gapperi galei)
Not taken yet in the Park but found in all the surrounding country, therefore, probable.
Common Field-mouse (Microtus pennsylvannicus modestus)
Recorded by Vernon Bailey from Lower Geyser Basin in the Park.
Long-tailed Vole (Microtus mordax)
Vernon Bailey records this from various surrounding localities, also from Tower Falls. Doubtless it is generally distributed. This is the bobtailed, short-eared, dark gray mouse that is found making runs in the thick grass, especially in low places.
Big-footed Vole (Microtus richardsoni macropus)
Not yet taken in the Park, but found in surrounding mountains, therefore probable.
Muskrat (Fiber zibethicus osoyoosensis)
Common and of general distribution.