Dark-eyed Junco
Junco hyemalis

Migratory Status: Short-distance migrant

PIF Population Estimate: 260 000 000

Percent of western hemisphere population breeding in boreal forest: 66%

BAM Effective Detection Radius (m) : 73.05

PIF Maximum Detection Distance (m) : 125

Canadian BBS Population trend: -1.8 (-2.5 to -1.1)

Life History

The Dark-eyed Junco is one of the most abundant and widely distributed landbirds in North America. Despite being relatively common, the species is not well known to most amateur birdwatchers and backyard bird enthusiasts. Its rather drab appearance, timid nature, and the fact that the bulk of its breeding range is far removed from human habitation, fosters this lack of familiarity. Although it is a common visitor to backyard bird feeders in winter, it forages mostly on the ground and rarely far from cover where it is often difficult to see.

This is a medium-sized sparrow with marked geographical variation in plumage, but typically with a distinct white underside and a variable gray to brown hood covering the back of its head and upper breast. Perhaps the most indicative feature, and often the field mark that is most frequently seen, is the band of conspicuous white outer-tail feathers that “flash” when the bird is in flight.

The song of the Dark-eyed Junco, while sung loudly and frequently by territorial males is not always a reliable means of identifying the species. Often described as a bell-like trill, it is similar to and often confused with the songs of as many as six other species with similar habitat preferences, including the Chipping Sparrow (Spizella passerine), Swamp Sparrow (Melospiza Georgiana), and Pine Warbler (Dendroica pinus). With some practice observers can differentiate species based on their songs, but the wide vocal array of individuals within each species sometimes requires a visual confirmation to ensure proper identification.

The breeding range of the Dark-eyed Junco includes most of the boreal forest region of Canada and Alaska, along with the major mountain ranges of the western and northeastern United States. Given this widespread distribution and apparent tolerance for a range of ecological conditions, the species is also exceptionally variable in appearance, vocalizations, and general ecology. As such, a total of 15 subspecies are recognized from 5 morphologically distinct groups.

Reference(s)

Nolan, Jr., V., E. D. Ketterson, D. A. Cristol, C. M. Rogers, E. D. Clotfelter, R. C. Titus, S. J. S 2002. Dark-eyed Junco (Junco hyemalis), The Birds of North America Online, . A. Poole, Ed. Ithaca: Cornell Laboratory of Ornithology; Retrieved from The Birds of North America Online database: http://bna.birds.cornell.edu/bna/species/716