NPSpecies

Park Species Data Source: Split from Junco hyemalis per Chris Woods state CBC compiler via Cynthia Melcher email 12/12/2003 per Jeff Connor Updated on 5/16/2018 by Mike Britten. The Birds of North America species account for Dark-eyed Junco identifies Junco hyemalis mearnsii as a subspecies of J. hyemalis in the "Oregon Junco group." BNA says J. h. mearnsii: "Breeds mountainous region centered around Yellowstone Plateau and Teton Range from se. Alberta and sw. Saskatchewan south through e. Idaho, central Montana, and ne. Wyoming; winters from n. Utah, nw. Wyoming, and central Nebraska south to n. Sonora, central Chihuahua, and w. Texas; regular west to e. California and casual to Pacific Coast; accidental east to Virginia (Iliff 2000)." According to Luekering and Mlodinow (Colorado Birds: Jul 2017 51(3); In the Scope: Selected Bird Subspecies of Interest in Colorado: Part 1 Tony Leukering and Steven G. Mlodinow), this taxon "...is about the most numerous wintering junco in the eastern portion of the state." This taxon may occur in Rocky Mountain NP and should be looked for.