Brown Creeper Certhia americana Scientific name definitions

“The brown creeper, as he hitches along the bole of a tree, looks like a fragment of detached bark that is defying the law of gravitation by moving upward over the trunk, and as he flies off to another tree he resembles a little dry leaf blown about by the wind.”Tyler 1948a Tyler, W. M. (1948a). "Brown Creeper." In Life histories of North American nuthatches, wrens, thrashers and their allies., edited by A. C. Bent, 56-79. U.S. Natl. Mus. Bull. no. 195. Close : 56

One of the continent's most inconspicuous songbirds, the Brown Creeper is the only treecreeper in North America. Its cryptic coloration and high-pitched vocalizations make it difficult to detect, yet it is widely distributed in coniferous, mixed, and deciduous forests throughout North America, from Alaska and Canada south to northern Nicaragua. In its endless pursuit of bark-dwelling invertebrates, it begins at the base of a tree trunk, climbs upward, sometimes spiralling around the trunk until it nears the top, then flies to the base of a nearby tree to begin the process again. This creeper uses its slender, decurved bill to glean invertebrates—mainly insects, spiders, and pseudoscorpions—from furrows in the bark. It was not until 1879 that naturalists discovered its unique habit of building its hammock-like nest behind a loosened flap of bark on a dead or dying tree.

The sole representative of its family in North America, the Brown Creeper is almost indistinguishable from its Old World counterpart, the Eurasian Treecreeper (Certhia familiaris), and they were long considered conspecific. In the last decade, the systematics of treecreepers were investigated using vocalizations, morphological traits, and molecular data. These studies have confirmed that Brown Creeper and Eurasian Treecreeper should be treated as separate species.

Although the Brown Creeper is found in a variety of forest habitats, it favors forest stands with an abundance of dead or dying trees for nesting and large live trees for foraging. It is most abundant in mature and old forests in summer but uses a wider variety of wooded habitats in winter. In recent decades, its numbers have increased in northern hardwood forests, possibly as a result of reforestation and the widespread mortality of trees due to gypsy-moths (Lymantria dispar) and other alien insect pests. Its breeding range appears to be expanding in mid-Atlantic states, the Midwest, Georgia, and California, although local extirpations are known due to habitat loss in New York, Michigan, and the lower Colorado River Valley. This creeper is often considered a year-round resident throughout its breeding range, but northern and high-altitude populations migrate. It is territorial during the breeding season, but in winter often joins mixed-species foraging flocks and roosts communally with other Brown Creepers.

Populations of this species have declined since presettlement times in northwestern Douglas fir (Pseudotsuga menziesii) forests owing to loss of mature and old-growth trees (Raphael et al. 1988 Raphael, M. G., K. V. Rosenberg and B. G. Marot. (1988). Large-scale changes in bird populations of Douglas-fir forests, northwestern California. Bird Conserv. 3:63-83. Close ), and in southwestern ponderosa pine (Pinus ponderosa; Brawn and Balda 1988b Brawn, J. D. and R. P. Balda. (1988b). "The influence of silvicultural activity on ponderosa pine forest bird communities in the southwestern United States." In Bird conservation 3., edited by J. A. Jackson. Madison: Int. Council for Bird Preservation U.S. section. Univ. of Wisconsin Press. Close ) owing to loss of mature pines. Current population-trend information indicates the species is stable in most areas in North America. North American Breeding Bird Survey (BBS) trend data, however, should be viewed with caution owing to the low number of individuals counted on routes and biases associated with roadside surveys. It is highly likely that creeper numbers have continued to decline in the West as a result of timber-harvesting practices. Degradation of habitat via the harvesting of large, live trees, salvage-logging practices that remove dead or dying trees, and the increasing fragmentation of forests, particularly in western North America, are the greatest known threats to current populations. Loss of large trees to exotic insects and diseases and the eventual loss of large snags in eastern forests could also affect creepers negatively. Partners in Flight groups are concerned about Brown Creepers in Washington, Oregon, California, Idaho, Montana, and the southern Blue Ridge and Sierra Nevada because of the negative effects of logging and forest fragmentation and the association of this species with large trees and a rare community type.

Despite the Brown Creeper's widespread distribution, more research is needed on almost every aspect of its biology, especially for Mexican and Central American populations. Key studies of this species include a comprehensive nesting study (Davis 1978a Davis, C. M. (1978a). A nesting study of the Brown Creeper. Living Bird 17:237-263. Close ), geographic variation in song (Baptista and Johnson 1982 Baptista, L. F. and R. B. Johnson. (1982). Song variation in insular and mainland California Brown Creepers. Journal of Ornithology 123:131-144. Close , Tietze et al. 2008), song analysis and taxonomic relationships (Baptista and Krebs 2000 Baptista, L. F. and R. Krebs. (2000). Vocalizations and relationships of Brown Creepers Certhia americana: a taxonomic mystery. Ibis 142:457-465. Close ), systematics (Webster 1986 Webster, J. D. (1986). "Certhia americana Bonaparte." In The known birds of North and Middle America, edited by A. R. Phillips, 195-212. Denver, CO: A. R. Phillips. Close , Unitt and Rea 1997 Unitt, P. and A. M. Rea. (1997). "Taxonomy of the Brown Creeper in California." In The era of Allan R. Phillips. A Fest shrift., edited by R. W. Dickerman, 177-185. Albuquerque, NM: R. W. Dickerman. Close , Tietze et al. 2006, Manthey et al. 2011a,b), foraging ecology (Franzreb 1985 Franzreb, K. E. (1985). Foraging ecology of Brown Creepers in a mixed-coniferous forest. Journal of Field Ornithology 56:9-16. Close , Morrison et al. 1987 Morrison, M. L., K. A. With, I. C. Timossi, W. M. Block and K. A. Milne (1987). Foraging behavior of bark-foraging birds in the Sierra Nevada. Condor 89:201-204. Close , Lundquist and Manuwal 1990 Lundquist, R. W. and D. A. Manuwal. (1990). Seasonal differences in foraging habitat of cavity-nesting birds in the southern Washington Cascades. Studies in Avian Biology 13:218-225. Close , Weikel and Hayes 1999 Weikel, J. M. and J. P. Hayes. (1999). The foraging ecology of cavity-nesting birds in young forests of the northern coast range of Oregon. Condor 101:58-66. Close ), and habitat use and requirements (Raphael and White 1984 Raphael, M. G., and M. White (1984). Use of snags by cavity-nesting birds in the Sierra Nevada. Wildlife Monographs 86:1–66. Close , Mariani 1987 Mariani, J. M. (1987). Brown Creeper (Certhia americana) abundance patterns and habitat use in the southern Washington Cascades. Master's Thesis, Univ. of Washington, Seattle. Close , Siegel 1989 Siegel, J. J. (1989). An evaluation of the minimum habitat quality standards for birds in old-growth ponderosa pine forests, northern Arizona. Master's Thesis, Univ. of Arizona, Tucson. Close , Mariani and Manuwal 1990 Mariani, J. M. and D. A. Manuwal. (1990). Factors influencing Brown Creeper (Certhia americana) abundance patterns in the southern Washington Cascade range. Studies in Avian Biology 13:53-57. Close , Keller and Anderson 1992 Keller, M. E. and S. H. Anderson. (1992). Avian use of habitat configurations created by forest cutting in southeastern Wyoming. Condor 94:55-65. Close , Adams and Morrison 1993 Adams, E. M. and M. L. Morrison. (1993). Effects of forest stand structure and composition on Red-breasted Nuthatches and Brown Creepers. Journal of Wildlife Management 57:616-629. Close , Freemark et al. 1995 Freemark, K. E., J. B. Dunning, S. J. Hejl and J. R. Probst. (1995). "A landscape ecology perspective for research, conservation, and management." In Ecology and management of Neotropical migratory birds: a synthesis and review of critical issues., edited by T. E. Martin and D. M. Finch, 381-427. New York: Oxford Univ. Press. Close , Hejl et al. 1995 Hejl, S. J., R. L. Hutto, C. R. Preston and D. M. Finch. (1995). "Effects of silvicultural treatments in the Rocky Mountains." In Ecology and management of Neotropical migratory birds: a synthesis and review of critical issues., edited by T. E. Martin and D. M. Finch, 220-244. New York: Oxford Univ. Press. Close , Poulin et al. 2008).