The Dark-eyed Junco (Junco hyemalis) is a species of the Juncos, a genus of small grayish American sparrows. This bird is common across much of temperate North America and in summer ranges far into the Arctic. It is a very variable species, much like the related Fox Sparrow (Passerella iliaca), and its systematics are still not completely untangled.

Adults generally have gray heads, necks, and breasts, gray or brown backs and wings, and a white belly, but show a confusing amount of variation in plumage details. The white outer tail feathers flash distinctively in flight and while hopping on the ground. The bill is usually pale pinkish. Males tend to have darker, more conspicuous markings than the females. [Wikipedia]

Dark-eyed Juncos are neat, even flashy little sparrows that flit about forest floors of the western mountains and Canada, then flood the rest of North America for winter. They’re easy to recognize by their crisp (though extremely variable) markings and the bright white tail feathers they habitually flash in flight. One of the most abundant forest birds of North America, you’ll see juncos on woodland walks as well as in flocks at your feeders or on the ground beneath them. [All About Birds]

Dark-eyed Junco Facts [All About Birds]

• Juncos are the “snowbirds” of the middle latitudes. Over most of the eastern United States, they appear as winter sets in and then retreat northward each spring. Some juncos in the Appalachian Mountains remain there all year round, breeding at the higher elevations. These residents have shorter wings than the migrants that join them each winter. Longer wings are better suited to flying long distances, a pattern commonly noted among other studies of migratory vs. resident species.

• The Dark-eyed Junco is one of the most common birds in North America and can be found across the continent, from Alaska to Mexico, from California to New York. A recent estimate set the junco’s total population at approximately 630 million individuals.

• The oldest recorded Dark-eyed Junco was at least 11 years, 4 months old when it was recaptured and re-released during banding operations in West Virginia in 2001. It had been banded in the same state in 1991.