Gray-tailed voles are sympatric with Townsend's vole (M. townsendii), with which they share many similarities. They can be distinguished by appearance, because Townsend's vole has darker colorings, a longer tail, and differences in the structure of the hard palate.
Gray-tailed voles coexist with Townsend's vole (M. townsendii) and exhibit similarities in many aspects. They can be differentiated by their appearance, as Townsend's vole has darker colors, a longer tail, and different hard palate structures.