Dark-eyed junco

The dark-eyed junco (Junco hyemalis) is a species of junco, a group of small, grayish New World 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.

Dark-eyed junco
Female slate-colored dark-eyed junco (Junco hyemalis hyemalis)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Passerellidae
Genus: Junco
Species:
J. hyemalis
Binomial name
Junco hyemalis
Approximate range in North America
  Breeding range
  Year-round range
  Wintering range
Synonyms
  • Fringilla hyemalis Linnaeus, 1758
  • Emeriza hyemalis Linnaeus, 1766
  • Junco aikeni Ridgway, 1873
  • Junco caniceps (Woodhouse, 1853)
  • Junco dorsalis Henry, 1858
  • Junco insularis Ridgway, 1876
  • Junco oreganus Towsend, 1837)

(but see text)

Description
Male slate-colored dark-eyed junco (J. h. hyemalis)

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.[2]

Males tend to have darker, more conspicuous markings than the females. The dark-eyed junco is 13 to 17.5 cm (5.1 to 6.9 in) long and has a wingspan of 18 to 25 cm (7.1 to 9.8 in).[2][3] Body mass can vary from 18 to 30 g (0.63 to 1.06 oz).[2] Among standard measurements, the wing chord is 6.6 to 9.3 cm (2.6 to 3.7 in), the tail is 6.1 to 7.3 cm (2.4 to 2.9 in), the bill is 0.9 to 1.3 cm (0.35 to 0.51 in) and the tarsus is 1.9 to 2.3 cm (0.75 to 0.91 in).[4] Juveniles often have pale streaks and may even be mistaken for vesper sparrows (Pooecetes gramineus) until they acquire adult plumage at 2 to 3 months, but junco fledglings' heads are generally quite uniform in color already, and initially their bills still have conspicuous yellowish edges to the gape, remains of the fleshy wattles that guide the parents when they feed the nestlings.

The song is a trill similar to the chipping sparrow's (Spizella passerina), except that the red-backed dark-eyed junco's (see below) song is more complex, similar to that of the yellow-eyed junco (Junco phaeonotus). The call also resembles that of the black-throated blue warbler's, which is a member of the New World warbler family.[5]Calls include tick sounds and very high-pitched tinkling chips.[6]It is known among bird language practitioners as an excellent bird to study for learning "bird language."

A sample of the song can be heard at the USGS web site here (MP3) or at the Cornell Lab of Ornithology web site here.

Taxonomy

The dark-eyed junco was described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae as Fringilla hyemalis. The description consisted merely of the laconic remark "F[ringilla] nigra, ventre albo. ("A black 'finch' with white belly"), a reference to a source, and a statement that it came from America.[7]

Linnaeus' source was Mark Catesby who described the slate-colored dark-eyed junco before binomial nomenclature as his "snow-bird", moineau de neige or passer nivalis ("snow sparrow") thus:

The Bill of this Bird is white: The Breast and Belly white. All the rest of the Body black; but in some places dusky, inclining to Lead-color. In Virginia and Carolina they appear only in Winter: and in Snow they appear most. In Summer none are seen. Whether they retire and breed in the North (which is most probable) or where they go, when they leave these Countries in Spring, is to me unknown. [italics in original][8]

The slate-colored dark-eyed junco is unmistakable enough to make it readily recognizable even from Linnaeus' minimal description.

Junco is the Spanish word for rush, from the Latin word juncus.[9] Its modern scientific name means "winter junco", from the Latin word hyemalis "of the winter".[10]

Subspecies

The several subspecies make up two large or polytypic groups and three to four small or monotypic ones. The six basic groups were formerly considered separate species (and the Guadalupe junco frequently still is), but they interbreed extensively in areas of contact. Birders trying to identify subspecies are advised to consult detailed identification references.[6][11]

Slate-colored group
Male and female Junco hyemalis
  • slate-colored dark-eyed junco (J. h. hyemalis)
  • Carolina dark-eyed junco (J. h. carolinensis)
  • Cassiar dark-eyed junco (J. h. cismontanus; possibly a slate-colored dark-eyed junco x Oregon dark-eyed junco hybrid)

These subspecies have dark slate-gray heads, breasts and upperparts. Females are brownish-gray, sometimes with reddish-brown flanks.[6] They breed in North American taiga forests from Alaska to Newfoundland and south to the Appalachian Mountains, wintering throughout most of the United States. They are relatively common across their range.

White-winged group
  • white-winged dark-eyed junco (J. h. aikeni)

The white-winged dark-eyed junco has a medium-gray head, breast, and upperparts with white wing bars. Females are washed brownish. It has more white in the tail than the other subspecies. It is a common endemic breeder in the Black Hills area of South Dakota, Wyoming, Nebraska, and Montana, and winters south to northeastern New Mexico.[2][6]

Oregon group
Oregon dark-eyed junco
  • Montana dark-eyed junco (J. h. montanus)
  • Oregon dark-eyed junco (J. h. oreganus)
  • Point Pinos dark-eyed junco (J. h. pinosus)
  • Hanson Laguna dark-eyed junco (J. h. pontilis)
  • Shufeldt's dark-eyed junco (J. h. shufeldti)
  • Thurber's dark-eyed junco (J. h. thurberi)
  • Townsend's dark-eyed junco (J. h. townsendi)

These subspecies have a blackish-gray head and breast with a brown back and wings and reddish flanks, tending toward duller and paler plumage in the inland and southern parts of its range.[11] Oregon dark-eyed juncos are less commonly known as brown-backed dark-eyed juncos. This is the most common subspecies group in the west, breeding in the Pacific Coast mountains from southeastern Alaska to extreme northern Baja California and wintering to the Great Plains and northern Sonora. An unresolved debate exists as to whether this large and distinct group is a full species.

Pink-sided dark-eyed junco

Pink-sided group
  • pink-sided dark-eyed junco (J. h. mearnsi)

Often considered part of the Oregon group, this subspecies has a lighter gray head and breast than the Oregon juncos, with contrasting dark lores. The back and wings are brown. It has a pinkish-cinnamon color that is richer and covers more of the flanks and breast than in the Oregon dark-eyed juncos. It breeds in the northern Rocky Mountains from southern Alberta to eastern Idaho and western Wyoming and winters in central Idaho and nearby Montana and from southwestern South Dakota, southern Wyoming, and northern Utah to northern Sonora and Chihuahua.[11]

Gray-headed dark-eyed junco

Gray-headed group
  • gray-headed dark-eyed junco (J. h. caniceps)

This subspecies is essentially rather light gray on top with a rusty back. It breeds in the southern Rocky Mountains from Colorado to central Arizona and New Mexico, and winters into northern Mexico.[2][6]

Red-backed group
  • red-backed dark-eyed junco (J. h. dorsalis)

Often included with J. h. caniceps as part of the "gray-headed group", this subspecies differs from the gray-headed junco proper in having a more silvery bill[11] with a dark-colored upper and light-colored lower mandible,[2][6] a variable amount of rust on the wings, and pale underparts. This makes it similar to the yellow-eyed junco (J. phaeonotus), except for the dark eyes. It is found in the southern mountains of Arizona and New Mexico.[6] It does not overlap with the yellow-eyed junco in its breeding range.

Guadalupe group
  • Guadalupe dark-eyed junco or Guadalupe junco (J. h. insularis or J. insularis, depending on the authority)

The extremely rare Guadalupe junco is also considered part of this species by some authorities, including the IUCN, which restored it to subspecies status in 2008.[12][13] Other authorities consider it a separate species in its own right – perhaps a rather young one, but certainly this population has evolved more rapidly than the mainland subspecies due to its small population size and the founder effect.

Ecology
Fledgling pink-sided dark-eyed junco (Junco hyemalis mearnsi) at about 1 month after hatching, Yellowstone National Park

Their breeding habitat is coniferous or mixed forest areas throughout North America. In otherwise optimal conditions they also utilize other habitat, but at the southern margin of its range it can only persist in its favorite habitat.[14] Northern birds migrate further south, arriving in their winter quarters between mid-September and November and leaving to breed from mid-March onwards, with almost all of them gone by the end of April or so.[14][15] Many populations are permanent residents or altitudinal migrants, while in cold years they may choose to stay in their winter range and breed there.[14] For example, in the Sierra Nevada of eastern California, J. hymealis populations will migrate to winter ranges 5,000–7,000 feet (1,500–2,100 m) lower than their summer range. In winter, juncos are familiar in and around towns, and in many places are the most common birds at feeders.[2] The slate-colored dark-eyed junco is a rare vagrant to western Europe and may successfully winter in Great Britain, usually in domestic gardens.

These birds forage on the ground. In winter, they often forage in flocks that may contain several subspecies. They mainly eat insects and seeds. A flock has been known to be called a blizzard.

Nest with eggs

They usually 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 have an outer diameter of about 10 cm (3.9 in) and are lined with fine grasses and hair. Normally two clutches of four 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 spotting is concentrated at the large end of the egg. The eggs are incubated by the female for 12 to 13 days. The young leave the nest between 11 and 14 days after hatching.

References
Junco hyemalis in flight
  1. BirdLife International (2012). "Junco hyemalis". IUCN Red List of Threatened Species. 2012. Retrieved 26 November 2013.CS1 maint: ref=harv (link)
  2. Cornell Lab of Ornithology (2002): Bird Guide – Dark-eyed junco. Retrieved 20 January 2007.
  3. Rising, J.D. (2010) A Guide to the Identification and Natural History of the Sparrows of the United States and Canada. Christopher Helm Publishers, London, ISBN 1408134608.
  4. Sparrows and Buntings: A Guide to the Sparrows and Buntings of North America and the World by Clive Byers & Urban Olsson. Houghton Mifflin (1995). ISBN 978-0395738733.
  5. "Black-throated Blue Warbler (Dendroica caerulescens)". Birds in Forested Landscapes. Cornell Lab of Ornithology.
  6. Sibley, David Allen (2000): The Sibley Guide to Birds. Alfred A. Knopf, New York, pp. 500–502, ISBN 0-679-45122-6
  7. Linnaeus, Carl (1758): 98.30. Fringilla hyemalis. In: Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (10th ed., vol.1): 183. Laurentius Salvius, Holmius (= Stockholm).
  8. Catesby, Mark (1731): 36. Passer nivalis. In: The Natural History of Carolina, Florida and the Bahamas (vol.1): Spread 65.
  9. "Junco". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  10. Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London, United Kingdom: Christopher Helm. pp. 197, 212. ISBN 978-1-4081-2501-4.
  11. Dunn, Jon L. (2002). "The identification of Pink-sided Juncos, with cautionary notes about plumage variation and hybridization". Birding. 34 (5): 432–443.
  12. BirdLife International (2008) Guadalupe junco species factsheet. Retrieved 26 May 2008.
  13. BirdLife International (2008): 2008 IUCN Red List status changes Retrieved 23 May 2008.Archived August 28, 2007, at the Wayback Machine
  14. Ohio Ornithological Society (2004): Annotated Ohio state checklist Archived July 18, 2004, at the Wayback Machine
  15. Henninger, W.F. (1906). "A preliminary list of the birds of Seneca County, Ohio" (PDF). Wilson Bulletin. 18 (2): 47–60.

Further reading

Book
  • Nolan, V., Jr., E. D. Ketterson, D. A. Cristol, C. M. Rogers, E. D. Clotfelter, R. C. Titus, S. J. Schoech, and E. Snajdr. 2002. "Dark-eyed Junco (Junco hyemalis)" in The Birds of North America, No. 716 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Theses
  • Dolan PM. Ph.D. (1982). Dominance, Aggression, and Social Power in Winter Flocks of the Dark-Eyed Junco (Junco hyemalis). University of Montana, United States – Montana.
  • Swanson DL. Ph.D. (1990). Seasonal thermoregulation in the dark-eyed junco (Passeriformes:Junco hyemalis). Oregon State University, United States – Oregon.
  • Terrill SB. Ph.D. (1986). The Relationship Between Social Dominance, Migratory Restlessness and Energetics in the Dark-Eyed Junco, Junco hyemalis, (L) (Birds, Physiology, Dispersal). State University of New York at Albany, United States – New York.

Morphology
  • Mulvihill RS & Chandler CR. (1990). The Relationship between Wing Shape and Differential Migration in The Dark-Eyed Junco. Auk. vol. 107, no. 3. pp. 490–9
  • Mulvihill RS & Chandler CR. (1991). A Comparison of Wing Shape Between Migratory and Sedentary Dark-Eyed Juncos (Junco-hyemalis). Condor. vol. 93, no. 1. pp. 172–5
  • Neal, Joseph C. (2003). "The Junco Challenge: A Genuine Pink-sided Junco from Arkansas and Some Look-alikes" Birding 35 (#2): 132–6

Behavior
  • Allan TA. (1979). Parental Behavior of a Replacement Male Dark-Eyed Junco Junco-Hyemalis. Auk. vol. 96, no. 3. pp. 630–631.
  • Baker MC, Belcher CS, Deutsch LC, Sherman GL & Thompson DB. (1981). Foraging Success in Junco Junco-Hyemalis Flocks and the Effects of Social Hierarchy. Anim Behav. vol. 29, no. 1. pp. 137–142.
  • Balph MH. (1979). Flock Stability in Relation to Social Dominance and Agonistic Behavior in Wintering Dark-Eyed Juncos Junco-Hyemalis. Auk. vol. 96, no. 4. pp. 714–722.
  • Boysen AF, Lima SL & Bakken GS. (2001). Does the thermal environment influence vigilance behavior in dark-eyed juncos (Junco hyemalis)? An approach using standard operative temperature. J Therm Biol. vol. 26, no. 6. pp. 605–612.
  • Butler RW. (1980). Appropriation of an American Robin Turdus-Migratorius Nest by Dark-Eyed Juncos Junco-Hyemalis-Oreganus. Canadian Field-Naturalist. vol. 94, no. 2.
  • Caraco T. (1981). Energy Budgets, Risk and Foraging Preferences in Dark-Eyed Juncos (Junco-hyemalis). Behavioral Ecology and Sociobiology. vol. 8, no. 3. pp. 213–217.
  • Clotfelter ED, Schubert KA, Nolan V & Ketterson ED. (2003). Mouth color signals thermal state of nestling dark-eyed juncos (Junco hyemalis). Ethology. vol. 109, no. 2. pp. 171–182.
  • Corbitt C & Deviche P. (2005). Age-related difference in size of brain regions for song learning in adult male dark-eyed juncos (Junco hyemalis). Brain Behavior & Evolution. vol. 65, no. 4. pp. 268–277.
  • Cristol DA. (1992). Food Deprivation Influences Dominance Status in Dark-Eyed Juncos Junco-Hyemalis. Anim Behav. vol. 43, no. 1. pp. 117–124.
  • Cristol DA. (1995). Costs of switching social groups for dominant and subordinate dark-eyed juncos (Junco hyemalis). Behavioral Ecology & Sociobiology. vol. 37, no. 2. pp. 93–101.
  • Cristol DA, Nolan VJ & Ketterson ED. (1990). Effect of Prior Residence on Dominance Status of Dark-Eyed Juncos Junco-Hyemalis. Anim Behav. vol. 40, no. 3. pp. 580–586.
  • Czikeli H. (1983). Agonistic Interactions within a Winter Flock of Slate-Colored Juncos Junco-Hyemalis Evidence for the Dominants Strategy. Zeitschrift für Tierpsychologie. vol. 61, no. 1. pp. 61–66.
  • Deviche P & Gulledge CC. (1998). Vocal control region volumes of an adult, sexually dimorphic songbird (Junco hyemalis) change seasonally in both sexes. Society for Neuroscience Abstracts. vol. 24, no. 1–2.
  • Fretwell S. (1969). Dominance Behavior and Winter Habitat Distribution in Juncos Junco-Hyemalis. Bird Banding. vol. 40, no. 1. pp. 1–25.
  • Goldman P. (1980). Flocking as a Possible Predator Defense in Dark-Eyed Juncos Junco-Hyemalis. Wilson Bull. vol. 92, no. 1. pp. 88–95.
  • Goldstein GB & Baker MC. (1984). Seed Selection by Juncos Junco-Hyemalis. Wilson Bull. vol. 96, no. 3. pp. 458–463.
  • Grindstaff JL, Buerkle CA, Casto JM, Nolan V & Ketterson ED. (2001). Offspring sex ratio is unrelated to male attractiveness in dark-eyed juncos (Junco hyemalis). Behavioral Ecology and Sociobiology. vol. 50, no. 4. pp. 312–316.
  • Hill JA, Enstrom DA, Ketterson ED, Nolan V & Ziegenfus C. (1999). Mate choice based on static versus dynamic secondary sexual traits in the dark-eyed junco. Behav Ecol. vol. 10, no. 1. pp. 91–96.
  • Holberton RL, Able KP & Wingfield JC. (1989). Status Signalling in Dark-Eyed Juncos Junco-Hyemalis Plumage Manipulations and Hormonal Correlates of Dominance. Anim Behav. vol. 37, no. 4. pp. 681–689.
  • Jawor MM & Ketterson ED. (2003). Dominance status influences breeding success in female dark-eyed juncos (Junco hyemalis). Integr Comp Biol. vol. 43, no. 6. pp. 861–861.
  • Keiser JT, Ziegenfus CWS & Cristol DA. (2005). Homing success of migrant versus nonmigrant dark-eyed juncos (Junco hyemalis). Auk. vol. 122, no. 2. pp. 608–617.
  • Ketterson ED. (1979). Aggressive Behavior in Wintering Dark-Eyed Juncos Junco-Hyemalis Determinants of Dominance and Their Possible Relation to Geographic Variation in Sex Ratio. Wilson Bull. vol. 91, no. 3. pp. 371–383.
  • Ketterson ED & Nolan VJ. (1978). Over Night Weight Loss in Dark-Eyed Juncos Junco-Hyemalis. Auk. vol. 95, no. 4. pp. 755–758.
  • Ketterson ED & Nolan VJ. (1979). Seasonal Annual and Geographic Variation in Sex Ratio of Wintering Populations of Dark-Eyed Juncos Junco-Hyemalis. Auk. vol. 96, no. 3. pp. 532–536.
  • Ketterson ED & Nolan VJ. (1982). The Role of Migration and Winter Mortality in the Life History of a Temperate Zone Migrant the Dark-Eyed Junco Junco-Hyemalis-Hyemalis as Determined from Demographic Analyses of Winter Populations. Auk. vol. 99, no. 2. pp. 243–259.
  • Ketterson ED & Nolan VJ. (1983). Autumnal Zugunruhe and Migratory Fattening of Dark-Eyed Juncos Junco-Hyemalis Apparently Suppressed by Detention at the Wintering Site. Wilson Bull. vol. 95, no. 4. pp. 628–635.
  • Lima SL. (1988). Vigilance and Diet Selection a Simple Example in the Dark-Eyed Junco. Canadian Journal of Zoology. vol. 66, no. 3. pp. 593–596.
  • Lima SL, Zollner PA & Bednekoff PA. (1999). Predation, scramble competition, and the vigilance group size effect in dark-eyed juncos (Junco hyemalis). Behav Ecol Sociobiol. vol. 46, no. 2. pp. 110–116.
  • Merritt J & Martin EW. (1987). The Distribution and Turnover of S-35 Methionine As Influenced by Diet in the Dark-Eyed Junco (Junco-hyemalis). Comp Biochem Physiol A-Physiol. vol. 88, no. 3. pp. 443–445.
  • Murphy MT, Bakken GS & Erskine DJ. (1986). Metabolic Responses of Dark-Eyed Juncos (Junco-hyemalis, Aves) to Temperature and Wind. Am Zool. vol 26, no 4. p. A112-A112.
  • Nolan VJ & Ketterson ED. (1983). An Analysis of Body Mass Wing Length and Visible Fat Deposits of Dark-Eyed Juncos Junco-Hyemalis Wintering at Different Latitudes. Wilson Bull. vol. 95, no. 4. pp. 603–620.
  • Nolan VJ, Ketterson ED & Wolf L. (1986). Long-Distance Homing by Nonmigratory Dark-Eyed Juncos Junco-Hyemalis. Condor. vol 88, no 4. pp. 539–542.
  • Rabenold KN & Rabenold PP. (1985). Variation in Altitudinal Migration Winter Segregation and Site Tenacity in Two Subspecies of Dark-Eyed Juncos Junco-Hyemalis in the Southern Appalachians USA. Auk. vol. 102, no. 4. pp. 805–819.
  • Rambo TC. (1981). Social Hierarchy and Activity in Caged Flocks of Dark-Eyed Juncos Junco-Hyemalis. Ohio Journal of Science. vol. 81, no. 1. pp. 24–28.
  • Rasner CA, Yeh P, Eggert LS, Hunt KE, Woodruff DS & Price TD. (2004). Genetic and morphological evolution following a founder event in the dark-eyed junco, Junco hyemalis thurberi. Mol Ecol. vol. 13, no. 3. pp. 671–681.
  • Roberts EPJ & Weigl PD. (1984). Habitat Preference in the Dark-Eyed Junco Junco-Hyemalis the Role of Photoperiod and Dominance. Anim Behav. vol. 32, no. 3. pp. 709–714.
  • Rogers CM, Nolan V, Jr. & Ketterson ED. (1994). Winter fattening in the dark-eyed junco: Plasticity and possible interaction with migration trade-offs. Oecologia. vol. 97, no. 4. pp. 526–532.
  • Rogers CM, Theimer TL, Nolan VJ & Ketterson ED. (1989). Does Dominance Determine How Far Dark-Eyed Juncos Junco-Hyemalis Migrate into Their Winter Range?. Anim Behav. vol. 37, no. 3. pp. 498–506.
  • Shettleworth SJ & Westwood RP. (2002). Divided attention, memory, and spatial discrimination in food-storing and nonstoring birds, black-capped chickadees (Poecile atricapilla) and dark-eyed juncos (Junco hyemalis). J Exp Psychol-Anim Behav Process. vol. 28, no. 3. pp. 227–241.
  • Smith KG. (1984). Dark-Eyed Junco, Junco-hyemalis, Nest Usurped by Pacific Jumping Mouse, Zapus-trinotatus. Can Field-Nat. vol. 98, no. 1. pp. 47–48.
  • Smith KG. (1988). Clutch-Size Dependent Asynchronous Hatching and Brood Reduction in Junco-hyemalis. Auk. vol. 105, no. 1. pp. 200–203.
  • Smith KG & Andersen DC. (1982). Food Predation and Reproductive Ecology of the Dark-Eyed Junco Junco-Hyemalis-Mearnsi in Northern Utah USA. Auk. vol. 99, no. 4. pp. 650–661.
  • Smith KG & Andersen DC. (1985). Snowpack and Variation in Reproductive Ecology of a Montane Ground-Nesting Passerine, Junco-hyemalis. Ornis Scandinavica. vol. 16, no. 1. pp. 8–13.
  • Soini HA, Schrock SE, Bruce KE, Wiesler D, Ketterson ED & Novotny MV. (2007). Seasonal variation in volatile compound profiles of preen gland secretions of the dark-eyed junco (Junco hyemalis). J Chem Ecol. vol. 33, no. 1. pp. 183–198.
  • Stuebe MM & Ketterson ED. (1982). Fasting in Tree Sparrows Spizella-Arborea and Dark-Eyed Juncos Junco-Hyemalis Ecological Implications. Auk. vol. 99, no 2. pp. 299–308.
  • Stuebe MM & Ketterson ED. (1982). A Study of Fasting in Tree Sparrows (Spizella-Arborea) and Dark-Eyed Juncos (Junco-hyemalis) – Ecological Implications. Auk. vol 99, no 2. pp. 299–308.
  • Swanson DL. (1990). Seasonal Variation in Cold Hardiness and Peak Rates of Cold-Induced Thermogenesis in the Dark-Eyed Junco Junco-Hyemalis. Auk. vol 107, no 3. pp. 561–566.
  • Swanson DL. (1991). Seasonal Adjustments in Metabolism and Insulation in the Dark-Eyed Junco. Condor. vol 93, no 3. pp. 538–545.
  • Terrill SB. (1987). Social Dominance and Migratory Restlessness in the Dark-Eyed Junco Junco-Hyemalis. Behavioral Ecology & Sociobiology. vol 21, no. 1. pp. 1–12.
  • Theimer TC. (1987). The Effect of Seed Dispersion On the Foraging Success of Dominant and Subordinate Dark-Eyed Juncos, Junco-hyemalis. Anim Behav. vol. 35, pp. 1883–1890.
  • Thompson DB, Tomback DF, Cunningham MA & Baker MC. (1987). Seed Selection by Dark-Eyed Juncos Junco-Hyemalis Optimal Foraging with Nutrient Constraints?. Oecologia. vol. 74, no. 1. pp. 106–111.
  • Vezina F & Thomas DW. (1997). Social rank and the use of nocturnal hypothermia in dark-eyed juncos (Junco hyemalis). Bulletin of the Ecological Society of America. vol. 78, no. 4 SUPPL.
  • Vezina F & Thomas DW. (2000). Social status does not affect resting metabolic rate in wintering dark-eyed junco (Junco hyemalis). Physiol Biochem Zool. vol. 73, no. 2. pp. 231–236.
  • Wiedenmann RN & Rabenold KN. (1987). The Effects of Social Dominance between Two Subspecies of Dark-Eyed Juncos Junco-Hyemalis. Anim Behav. vol. 35, no. 3. pp. 856–864.
  • Wiley RH. (1990). Prior-Residence and Coat-Tail Effects in Dominance Relationships of Male Dark-Eyed Juncos, Junco-hyemalis. Anim Behav. vol. 40, pp. 587–596.
  • Wiley RH & Hartnett SA. (1980). Mechanisms of Spacing in Groups of Juncos Junco-Hyemalis Measurement of Behavioral Tendencies in Social Situations. Anim Behav. vol. 28, no. 4. pp. 1005–1016.
  • Wolf L. (1983). An Experimental Study of Bi Parental Care in the Dark-Eyed Junco Junco-Hyemalis. Am Zool. vol 23, no 4. pp. 930–930.
  • Wolf L, Ketterson ED & Nolan VJ. (1988). Parental Influence on Growth and Survival of Dark-Eyed Junco Young Do Parental Males Benefit. Anim Behav. vol. 36, no. 6. pp. 1601–1618.
  • Yasukawa K & Bick EI. (1983). Dominance Hierarchies in Dark-Eyed Juncos Junco-Hyemalis a Test of a Game Theory Model. Anim Behav. vol. 31, no. 2. pp. 439–448.
  • Yaukey PH. (1994). Variation in Racial Dominance Within the Winter Range of the Dark-Eyed Junco (Junco-hyemalis L). J Biogeogr. vol. 21, no. 4. pp. 359–368.
  • Yunick RP. (1976). Rate of Rectrix Regrowth in Dark-Eyed Junco. Bird-Banding. vol. 47, no 2. pp. 136–140.

Status
  • Collins CT. (1987). A Breeding Record of the Dark-Eyed Junco on Santa Catalina Island California USA. Western Birds. vol. 18, no. 2. pp. 129–130.
  • Polder JJW & Voous KH. (1969). Capture of Slate-Colored Junco Junco-Hyemalis in the Netherlands. Limosa. vol. 42, no. 3–4. pp. 198–200.

Other
  • Bears H. (2004). Parasite prevalence in Dark-eyed Juncos, Junco hyemalis, breeding at different elevations. Can Field-Nat. vol. 118, no. 2. pp. 235–238.
  • Brackbill H. (1977). Protracted Prebasic Head Molt in the Dark-Eyed Junco. Bird Banding. vol. 48, no. 4. pp. 370–370.
  • Deviche P, Greiner EC & Manteca X. (2001). Seasonal and age-related changes in blood parasite prevalence in Dark-eyed Juncos (Junco hyemalis, Aves, Passeriformes). J Exp Zool. vol. 289, no. 7. pp. 456–466.
  • Jung RE, Morton ES & Fleischer RC. (1994). Behavior and Parentage of a White-Throated Sparrow X Dark-Eyed Junco Hybrid. Wilson Bull. vol. 106, no. 2. pp. 189–202.
  • Ketterson ED & Nolan VJ. (1976). Geographic Variation and Its Climatic Correlates in the Sex Ratio of Eastern Wintering Dark-Eyed Juncos Junco-Hyemalis-Hyemalis. Ecology. vol. 57, no. 4. pp. 679–693.
  • Simmons GA & Sloan NF. (1969). A New Bird Nest Monitoring Technique Inst Event Recorder Hylocichla-Guttata Junco-Hyemalis. American Midland Naturalist. vol. 81, no. 1. pp. 276–279.
  • Weske JS & Bridge D. (1976). Incomplete Pre-Basic Molt in a Dark-Eyed Junco. Bird-Banding. vol. 47, no. 3. pp. 276–277.
  • Worth CB. (1975). Pseudoscorpions On a Dark-Eyed Junco, Junco-hyemalis. Bird-Banding. vol. 46, no. 1. pp. 76–76.
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