Dark-eyed Junco
Junco hyemalis
Summary 7
The Dark-eyed Junco (Junco hyemalis) is the best-known 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 is still not completely untangled.
Distribution 8
Dark-eyed juncos (Junco hyemalis) breed from Alaska and central Yukon to Labrador and Newfoundland, south to central coastal California, in the mountains to eastern California, central Arizona, and western Texas, southern Alberta, northern and east-central Minnesota, central Michigan, southern New England, and in the Appalachian Mountains to northern Georgia and northwestern South Carolina; also in the Black Hills. This species winters from central and south coastal Alaska, coastal British Columbia and across southern Canada south to Mexico, the Gulf Coast and northern Florida. It is found only in the Nearctic region of the world.
Biogeographic Regions: nearctic (Native )
Morphology 9
All J. hyemalis are small and slender with an overall length of 5 to 6.5 inches (12.5 to 16.5 cm). This species has dark gray plumage on its head, breast and upper parts which are a contrast to their striking white, outer tail and white belly. Sexes are colored or patterned differently with female and immature J. hyemalis somewhat browner than the adult male; juveniles also have streaked breasts. Males are usually around 5% larger than females. Members of this species have a pink bill and dark eyes. A typical weight for J. hyemalis is 0.67 oz (19 g) and an average wingspan is 9.25 inches (23.5 cm).
Average mass: 19 g.
Range length: 12.5 to 16.5 cm.
Average wingspan: 23.5 cm.
Average basal metabolic rate: 46 cm3.O2/g/hr.
Other Physical Features: endothermic ; bilateral symmetry ; polymorphic
Sexual Dimorphism: male larger; sexes colored or patterned differently
Average mass: 18 g.
Average basal metabolic rate: 0.2959 W.
Habitat 10
The habitat of J. hyemalis occurs from sea level to timberline in a variety of woodland areas that have openings with dense herbaceous ground cover. These areas include coniferous and deciduous forests, forest edges, woodland clearings, stream borders, open woodlands, brushy cover bordering mountain meadows, and old barns. This species avoids deep forest interiors in favor of woodland edges and openings. In winter they prefer weedy fields, but also inhabit open woodlands, hedgerows, suburbs, and farmyards. They are found from sea level to 3500 meters.
Range elevation: 0 to 3500 m.
Habitat Regions: temperate ; polar ; terrestrial
Terrestrial Biomes: forest
Other Habitat Features: urban ; suburban ; agricultural ; riparian
Sources and Credits
- (c) Robin Horn, some rights reserved (CC BY-NC-ND), http://www.flickr.com/photos/powerkey/8133812669/
- (c) msr, some rights reserved (CC BY-NC), uploaded by msr
- (c) BJ Stacey, some rights reserved (CC BY-NC), http://farm9.staticflickr.com/8249/8600603941_e2e3bd7ac6_o.jpg
- (c) cyric, some rights reserved (CC BY-NC-SA), uploaded by cyric
- (c) James Maughn, some rights reserved (CC BY-NC), https://farm6.staticflickr.com/5576/14642769133_e6989bd341_o.jpg
- (c) Donna Pomeroy, some rights reserved (CC BY-NC), uploaded by Donna Pomeroy
- (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Junco_hyemalis
- (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31399966
- (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31399968
- (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31399967
