Junco, common name for three finch species that are
adept at cracking open seeds. The "slate-colored"
subspecies of dark-eyed junco (Junco hyemalis hyemalis)
is about 15 cm (6 in) long. Adult males are slate gray,
with a white abdomen and white outer tail feathers. Males
of the "Oregon" subspecies of dark-eyed juncos (Junco
hyemalis oreganus) have black or gray heads and rusty
backs. The volcano junco (Junco vulcani) has a brown and
black streaked back and lives in the mountains of Costa
Rica and Panama.
Scientific classification: Juncos make up the genus Junco
in the family Emberizidae.