Dark-eyed juncos (Junco hyemalis) are great little North American birds. The ornithological gurus have decided that the 15 color variations are really one species. They had to do this because the juncos persisted in interbreeding and creating little mixed families at their territorial margins. They are super easy to identify in eastern North America. They are the only small (about 6 inches) bird with white bellies found here. In addition to this they have their dark eyes and white/pink bills and white outer tail feathers. If you live in the Rocky Mountains things get a bit more confusing with gray bellies and dark bills.
In most (but not quite all) all of the US and Canada juncos may be permanent residents or temporary migrants at various times of year. In my area (USDA zone 7) they are especially loved because we see them as an early sign of spring. When the juncos flocks arrive there may still be snow on the ground but pussy willow, witch hazel, snowdrops, and species crocus will also be blooming! The juncos will hang around here for a few months before heading further south.
Juncos were the most common feeder birds in North America in a 1997 survey. In my experience, they are very fond of millet seed.
For birds, they are uncommonly attached to the earth. They are ground feeders, hopping and scratching on the ground as they search for seeds. They also like to nest on the ground or low on wall like surfaces. Males do favor high perches for singing.
On a recent summer vacation in Appalachia we were graced with the visits of what are locally called Carolina Juncos daily. The sunflower seeds left on the porch did help but this was their home anyway. They are territorial during the mating season, and monogamous. They won’t flock again until winter. On our last day there my daughter found a nest with fledging sized baby birds in a grapevine wreath on a seldom used door. I took a photo and the parents swept in with a mad chatter/scold. 4 little Juncos!
Juncos' normal song is described as a “ringing metallic trill on the same pitch” by enature.com and can be heard online there as well as at this URL: http://www.junglewalk.com/sound/Junco-sounds.asp. Like many, perhaps most, songbirds, the males sing to attract females and establish territories. This means songs are mostly limited to mating times. Both males and females also have a range of other short vocalizations, described as clicks or clucks. Research has shown that the junco learns his song from his daddy and neighbors, it is not innate. Juncos raised hearing only the songs of other species sing the other species songs.
Gough, G.A., Sauer, J.R., Iliff, M. Patuxent Bird Identification Infocenter. 1998. Version 97.1. Patuxent Wildlife Research Center, Laurel, MD. http://www.mbr-pwrc.usgs.gov/Infocenter/infocenter.html
Fred J. Alsop III, Smithsonian Handbook Birds of North America Eastern Region, 2001