Dark-Eyed Junco (Junco Hyemalis) Thomas A
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Dark-eyed Junco (Junco hyemalis) Thomas A. Allan Oakland Co., MI. 1/15/2009 © Darlene Friedman (Click to view a comparison of Atlas I to II) The Dark-eyed Junco is one of the most and New Mexico and the Appalachian distinctive and easily recognized sparrows in Mountains of the east (Nolan et al 2002). The Michigan. It is a taxonomic conglomerate of Slate-colored Junco group is distributed five previously distinct species and fifteen throughout much of northern and eastern North subspecies (Nolan et al. 2002). The Michigan America. This migratory species breeds in the form is part of the Slate-colored Junco group mid to high latitudes where suitable habitat characterized by its slate gray body and exists and winters widely across the eastern distinctive white outer tail feathers. The Dark- portion of the continent (Root 1988). eyed Junco can be found in Michigan throughout the year. Barrows (1912) found the Distribution junco to be a common summer resident of the The breeding habitat of the Dark-eyed Junco of northern half of the state and a common winter eastern North America is generally conifer or resident of the southern half of Michigan. boreal forests and its distribution in Michigan Juncos are often referred to as “snowbirds” appears to reflect this. The Dark-eyed Junco is a because they appear at bird feeders with the regular breeding bird of the northern two thirds arrival of winter, stay through the winter of Michigan where suitable conifer habitat is months, and then depart for their breeding found. There appears to be little difference in grounds with the arrival of spring. The song of the distribution of junco breeding in Michigan the male junco is a long ringing trill and one has from MBBA I to MBBA II. Both MBBA I and to listen carefully to discern it from the very MBBA II found the greatest concentration of similar Chipping Sparrow and Pine Warbler, breeding juncos in the LP to be in the conifer which can often be found in similar habitat as forests of Crawford, Kalkaska, and Oscoda the junco. Counties and several of the counties surrounding them. The sandy soils and jack pine When considering all subspecies of the Dark- forests where Kirtland’s Warblers breed are also eyed Junco, its range covers almost the entire good habitat for the Dark-eyed Juncos. North American continent. It breeds across the northern boreal forest from Alaska to Labrador The southern distribution of Dark-eyed juncos and into the south in montane forests of Arizona in Michigan drops off dramatically after leaving © 2010 Kalamazoo Nature Center Dark-eyed Junco (Junco hyemalis) Thomas A. Allan the conifer forests of the north, and the probable Abundance and Population Trends or possible records of breeding juncos in (Click to view trends from the BBS) southern Michigan may be associated with There was a slight increase in the number of conifer plantings. MBBA II found possible junco records in MBBA II from all regions of juncos breeding in several counties farther south the state (241 townships in MBBA I vs. 259 than MBBA I. The Dark-eyed Junco appears to townships in MBBA II). The results of MBBA be a fairly common breeder across the UP, with II confirm the Michigan distribution and concentrations of confirmed breeding in the abundance of the junco as found in MBBA I. boreal forests and conifer habitats of the Lake The occurrence of possible junco breeding in Superior watershed. Both MBBA I and MBBA southern regions of the state may be associated II found confirmed breeding concentrations of with better survey efforts for MBBA II, juncos on the sandy soils and conifer forests maturation of conifer plantations into suitable near Whitefish Point and the Raco Plains of junco breeding habitat, or just very late migrants Chippewa County, the conifer forests of lingering into the breeding season. The results northern Luce County, the Seney area, the of the North American Breeding Bird Survey conifer forests surrounding Marquette, and the show a statistically significant slight downward boreal forests of eastern Gogebic County in the trend for survey-wide junco populations, but no western UP. statistically significant trend in the Michigan population (Sauer et al. 2008). The Michigan It was absent in both MMBA I And MBBA II population of Dark-eyed Juncos appears to be from the agricultural lands of Menominee stable with perhaps a slight southern expansion County, uncommon in the grasslands and clay in its statewide breeding range. Breeding Bird soils of the eastern UP, and very localized in the Atlas surveys in other Midwest regions, such as extensive hardwood forests of the far western Wisconsin and New York (Cutright et al. 2006, UP. McGowan and Corwin 2008), have found no significant declines in junco populations. Breeding Biology Dark-eyed Juncos arrive on their Michigan Conservation Needs breeding grounds in April and May with With an apparently stable or slightly increasing courtship, nest building and egg laying population in Michigan, and no serious threats occurring in May and June (Allan 1978). Juncos to its widespread conifer habitat, there is no seem to prefer openings, clearings, and edges of immediate concern for Dark-eyed Junco the conifer forests rather than forest interiors. conservation. The distribution of the Dark-eyed Their ground nests are often located along forest Junco in Michigan should remain similar to that edges and are well concealed by a cover of described by Barrows (1912) almost a century grasses or brush. The nest bowl is often lined ago. with fine grasses, mammal hairs or other fine materials (Harrison 1975). Although generally very secretive around the nest, the parent juncos often become agitated when an intruder approaches their nest site. They conspicuously flash their white outer tail feathers as part of a predator distraction display. The typical clutch size of four hatches in June, with young still being fed by parents up to several weeks after hatching. © 2010 Kalamazoo Nature Center Dark-eyed Junco (Junco hyemalis) Thomas A. Allan Literature Cited Allan, T.A. 1978. The nesting ecology of the Dark-eyed Junco on the Baraga Jack Pine Plains . M.S. thesis. Houghton. Michigan Technological University Barrows, W.B. 1912. Michigan Bird Life. Special Bulletin. Michigan Agricultural College. Lansing, MI. Cutright, N.J., B.R. Harriman, and R.W. Howe. 2006. Atlas of the Breeding Birds of Wisconsin. Wisconsin Society for Ornithology. Waukesha, WI. Harrison, C. 1978. A Field Guide to Nests, Eggs, and Nestlings of North American Birds. William Collins Sons and Co. New York, NY. McGowan, K.J., and K. Corwin (eds.). 2008. The Second Atlas of Breeding Birds in New York State. Cornell University Press, Ithaca, NY. Nolan, V., E.D.Keterson, D.A. Cristol, C.M. Rogers, E.D. Clotfelter, R.C. Titus, S.J. Schoech, and E. Snajdr. 2002. Dark-eyed Junco. In The Birds of North America, No 716. (A. Poole and F. Gill, eds.) The Birds of North America Inc., Philadelphia, PA. Root. T. 1988. Atlas of Wintering North America Birds: An Analysis of Christmas Bird Count Data. Chicago. University of Chicago Press Sauer, J.R., J. Hine, and J. Fallon. 2008. The North American Breeding Bird Survey, Results and Analysis 1966-2007. Version 6.0 USGS Patuxent Wildlife Research Center. Laurel.MD Suggested Citation Allan, T.A. 2010. Dark-eyed Junco (Junco hyemalis). In Chartier, A.T., J.J. Baldy, and J.M. Brenneman (eds.). 2010. The Second Michigan Breeding Bird Atlas. Kalamazoo Nature Center. Kalamazoo, MI. Accessed online at: <www.mibirdatlas.org/Portals /12/MBA2010/DEJUaccount.pdf >. © 2010 Kalamazoo Nature Center .