[2] Western heather voles are mainly found in open coniferous forests that contain small shrubs or vegetation on the outskirts as well as meadows in British Columbia, Canada.

[3] The summer and winter diet of heather voles is predominantly kinnikinnick, a small shrub with evergreen leaves that produces red berries.

[3] The winter diet of Phenacomys intermedius is bark of bush willow, dwarf birch,sheep laurel, and blueberry.

[2] The range of western heather voles is restricted to the Pacific Northwest of North America, specifically Canada and they are the most common rodent in this area of the subfamily Microtinae.

This is thought to be due to the fact that P. intermedius mainly feed on leaves and berries while eating few seeds even when high in availability as shown in studies.

[7] Other than feeding behaviors, these mammals use short burrow systems during the summer months and build their nests for reproduction under a rock or stump.

[8] Additionally, fossils of P. intermedius from the Pleistocene age have been found in northern Arkansas and Tennessee which is much more south then the current distribution.

Lastly, during the Holocene time period, climatic change occurred and the only fit habitat was mountainous "islands" for the Phanacomys and eventually led to their extinction in certain areas such as the Great Basin range.

[4] It is estimated that the Heather vole diverged from its most closely related sister lineage in the same subfamily of Arvicolinae about 5.37 million years ago.