Dark-eyed juncos belong to a group of small grayish American sparrows. Adults generally have gray heads, necks, and breasts, gray or brown backs and wings, and a white belly. The white outer tail feathers flash distinctively in flight and while hopping on the ground. Their bill is usually pale pinkish.
Dark-eyed juncos are found throughout North America and in summer range far into the Arctic. Northern birds migrate further south but other populations are permanent residents. Dark-eyed juncos breed in coniferous or mixed forest areas, open woodlands, shrubland, and roadsides. In winter, they can be found in woodland edges, thickets, and in around towns.
Dark-eyed juncos are diurnal and spend their time foraging or perching. They forage on the ground walking or hopping around in search of seeds and may also run over short distances to catch insects. Dark-eyed juncos are social and in winter, they often forage in flocks with other subspecies. Juncos communicate with each other using calls that include 'tick' sounds and very high-pitched tinkling 'chips'.
Dark-eyed juncos are monogamous which means that one male mates only with one female. The breeding season usually begins in April; the birds nest in a cup-shaped depression on the ground, well hidden by vegetation or other material, although nests are sometimes found in the lower branches of a shrub or tree. The nests are lined with fine grasses and hair. Normally two clutches of 4 eggs are laid during the breeding season. The slightly glossy eggs are grayish or pale bluish-white and heavily spotted (sometimes splotched) with various shades of brown, purple or gray. The eggs are incubated by the female for 12 to 13 days. The chicks leave the nest between 11 and 14 days after hatching and become reproductively mature at 1 year of age.
There are no major threats facing Dark-eyed juncos at present.
According to the IUCN Red List, the total Dark-eyed jay population size is around 260 000 000 mature individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Dark-eyed juncos play an important role in their ecosystem; these little birds help to maintain forests in health and productivity. Due to their diet habits, juncos disperse seeds and help to control populations of various insects they prey on.