Scientific Name: Vireo plumbeus
Population Estimate: 2.7M, Least Concern status
Range / Habitat: Winters in western Mexico in montane moist forest. Summers in the southern Rockies and the Great Basin. it is a small North American songbird, ranging from far southeastern Montana and western South Dakota south to the Pacific coast of Mexico, including the extreme southern regions of Baja California Sur.
Field Notes: All grey head, back and tail with two weak, white wing bars. White spectacles are pronounced. White underneath, completely lacking yellow coloring of most other vireos. The Grey Vireo overlaps in range, but has a complete, thin eye ring and only one weak wing bar. At first glance may also be confused with a Blue-grey Gnatcatcher, who is smaller with longer tail, thinner bill, complete and narrow eye ring, and no wing bars.
Personal Notes: Formerly lumped as a "Solitary Vireo" with the more eastern Blue-headed Vireo and more northwestern Cassin's Vireo.