Golden-Winged Warbler (Vermivora Chrysoptera) Robert B

Golden-winged Warbler (Vermivora chrysoptera) Robert B. Payne

Jordan River Valley, MI 6/12/2009 © John Van Orman

(Click to view a comparison of Atlas I to II)

Golden-winged Warblers breed in northeastern Breeding Biology In Michigan, Golden-winged Warblers arrive in North America from New York, Pennsylvania, early May, breed in spring and early summer, southern Ontario and southern Manitoba to and leave in August (Barrows 1912). Territory Michigan, Wisconsin and Minnesota and south size averages 1.9 ha in Michigan (Murray & through the Appalachians into the mountains of Gill 1976, Will 1986); over a wider geographic North Carolina and eastern Tennessee. They are range, from 0.4 to 6.0 ha (Confer 1992, Confer long-distance migrants and in winter they occur and Larkin 1998). In Michigan the first nests are from Central America to extreme northwestern built 21 May - 1 June; when nests are lost, South America (Confer 1992). In addition to replacement nests are built in June and into their distinctive plumage of a yellow cap and early July. After a successful first nest, second wing bars and a broad black mask and black nestings are unknown. Nests are an open cup of throat, the songs of Golden-winged Warblers grass placed on the ground, well concealed, in are distinct from songs of the related Blue- the shade and often along edges of forest and winged Warbler. One set of Golden-winged field. The warblers sometimes are brood- Warbler songs (accented song, type 1) is a parasitized by Brown-headed Cowbirds (Will distinctive "bee-buzz-buzz-buzz", differing from 1986, Confer 1992). the "bee-buzz" of Blue-winged Warblers. The other songs (unaccented song, type 2) are more Where Golden-winged Warblers occur together similar in the two species, and these songs vary with Blue Winged Warblers, the two species among localities within the species (Confer sometimes occur on overlapping territories and 1992, Gill et al. 2001). are not aggressive toward each other, and other

times they occur on exclusive neighboring Distribution territories and are aggressive toward each other. In Michigan the Golden-winged Warbler occurs They often interbreed and produce hybrid young mainly in the NLP and the UP; they also occur (Berger 1958, Gill & Murray 1972a, 1972b, in scattered localities in the SLP. Their breeding Murray & Gill 1976, Gill 1980, 2004). habitat is found primarily in early successional Interspecific hybridization is an important stages of woodlands, along the edges of fields aspect in the biology of these warblers. The and in shrubby wetlands. hybrids and the offspring of hybrids are sometimes known as "Brewster's Warbler" and

"Lawrence's Warbler". Birds identified as In the SLP in MBBA I they were in 15% of the backcross hybrids ("Lawrence's Warbler", the townships, in MBBA II they were in 4%. In the most readily identified intermediate form, with NLP Golden-winged Warblers appeared in 33% yellow and a black mask and bib) were recorded of the townships in MBBA I and in 26% in in MBBA I and MBBA II in the SLP, where MBBA II. In the UP the proportion of Blue-winged Warblers have largely replaced the townships with warblers was 16% in MBBA I Golden-winged Warblers. and 12% in MBBA II. A decrease in distribution occurred mainly in central and western UP in In southern Ontario, Golden-winged Warblers Delta, Marquette and Ontonagon Counties. mate with their own species or with Blue- winged Warblers at random in relation to the Golden-winged Warblers have undergone a local abundance of the two species. The hybrid steady and significant decline in numbers warblers are as successful in reproduction and observed in Breeding Bird Surveys in Michigan fledging as are conspecific pairs of Golden- between 1966 and 2006, from about 0.5 birds winged Warblers (Reed et al. 2007, Vallender et per route in the first five years of the survey to al. 2007a, 2007b). The breeding biology of less than one bird per route in the last five years. these warblers is further noteworthy in that Throughout the warbler's range in North more than 30% of nestling warblers in a mixed- America, a significant decrease in breeding species population were the result of extra-pair numbers occurred from 0.5-0.6 birds per survey copulations, and genetic mismatches of the route in 1966-1970 to fewer than 0.3 birds in the social father (the male on whose territory the years 2000-2004, an annual rate of decrease of female nested, and her social mate) and the 3.4% (Sauer et al. 2008). In neighboring genetic father of the nestlings were seen in 55% Wisconsin and southern Ontario their numbers of the broods. and their distributional area in the breeding season also have declined (Cutright et al. 2006, Abundance and Population Trends Cadman et al. 2007). In Ontario the birds now (Click to view trends from the BBS) are found mainly along the southern edge of the During the late 1800s and early 1900s in North Shield, and these concentrations have shifted America, Golden-winged Warblers expanded northward from the previous atlas period of their distribution northward into Michigan (Gill 1981 to 1985 when the Golden-winged 1982, 2004, Confer 1992). In Michigan, they Warblers were mostly in the southernmost parts occurred mainly in the SLP and generally were of the province (Cadman et al. 2007). In the past not found in the NLP, although as early as 1891 50 years in counts of migrating birds banded at they were reported as far north as Mackinaw Long Point on Lake Erie in southern Ontario, City (Barrows 1912). In the UP they were the numbers of Golden-winged Warblers reported in 1921, yet by 1940 they were hardly relative to Blue-winged Warblers have known in that region (Wood 1951). The first decreased from more than 200% to only 15% observations in the Keweenaw Peninsula were (COSEWIC 2006). Throughout their range the in 1963-1977, the earliest summer record was in global population of Golden-winged Warblers is 1981, and summering birds have increased in estimated to be about 210,000 birds, and the numbers in more recent years (Binford 2006). species is considered "Near Threatened" (BirdLife International 2009). In the past few years, Golden-winged Warblers have become less widespread in Michigan. In the southern three tiers of counties in the SLP, they were recorded in 37 townships in MBBA I; they were in only seven townships in MBBA II.

Conservation Needs Literature Cited In Michigan, the decrease in Golden-winged Warblers coincided in time with the northward Barrows, W.B. 1912. Michigan Bird Life. extension of Blue-winged Warblers, a process Special Bulletin. Michigan Agricultural that has continued in Michigan and elsewhere in College. Lansing, MI. eastern North America through the past century Berger, A.J. 1958. The Golden-winged – Blue- (Confer 1992, Cutright et al. 2006, Buehler et winged Warbler complex in Michigan and al. 2007, Cadman et al. 2007, McGowan & the Great Lakes area. Jack-Pine Warbler 36: Corwin 2008). However the decrease in 37-73. numbers in the UP was not owing to Binford, L.C. 2006. Birds of the Keweenaw competition with Blue-winged Warblers, Peninsula, Michigan. Miscellaneous because that species was observed in only four Publications, Museum of Zoology, UP township localities in MBBA II and the University of Michigan, no. 195. Golden-winged Warblers were seen in 77 BirdLife International. 2009. Species factsheet: township localities. Golden-winged Warblers as Vermivora chrysoptera. a species are challenged by the widespread . introgression of genes of the expanding Blue- Buehler, D.A., A.M. Roth, R. Vallender, T.C. winged Warblers. As many as a third of the Will, J.L. Confer, R.A. Canterbury, S.B. birds in Golden-winged Warbler plumage have Swarthout, K.V. Rosenberg and L.P. Blue-winged Warbler genes, owing to Bulluck. 2007. Status and conservation hybridization and genetic introgression; and priorities of Golden-winged Warbler introgression is two-way, Golden-winged (Vermivora chrysoptera) in North America. Warbler genes moving into populations of Blue- Auk 124: 1439-1446. winged Warblers (Shapiro et al. 2004, Vallender Cadman, M.D., D.A. Sutherland, G.G. Beck, D. et al. 2007a, 2007b). The northward extension Lepage and A.R. Courtier, eds. 2007. Atlas of Blue-winged Warblers and introgression of of the Breeding Birds of Ontario, 2001- their genes into populations of Golden-winged 2005. Bird Studies Canada, Environment Warblers, as well as the decline of Golden- Canada, Ontario Field Ornithologists, winged Warblers in northern Michigan, may be Ontario Ministry of Natural Resources, and associated with the widespread climatic Ontario Nature. Toronto, Ontario. warming in the region through the past century. Confer, J.L. 1992. Golden-winged Warbler Binford (2006) suggests that suitable habitat (Vermivora chrysoptera). In Birds of North such as aspens at the edge of bogs, beaver ponds America, No. 20. and deciduous swamps occurred in northern http://bna.birds.cornell.edu.bnaproxy.birds.c Michigan even before logging opened the ornell.edu/bna/species/020. habitat and extended the areas where warblers Confer, J.L. and J.L. Larkin. 1998. Behavioral now occur in summer. In the UP a recent interactions between Golden-winged and increase in forest cover may also be involved in Blue-winged Warblers. Auk 115:209-214. the decline of Golden-winged Warblers. COSEWIC. 2006. COSEWIC assessment and Elsewhere in their range, a cycle of burning status report on the Golden-winged Warbler areas of forest has been proposed to manage Vermivora chrysoptera. Committee on the suitable habitat of secondary growth woodland Status of Endangered Wildlife in Canada, and scrub (Confer 1992). Ottawa / www.sararestry.gc.ca/status/statuse.cfm. Cutright, N.J., B.R. Harriman and R.W. Howe. 2006. Atlas of the Breeding birds of

Wisconsin. Wisconsin Society for Vallender, R., V.L. Friesen and R.J. Robertson. Ornithology, Waukesha. 2007. Paternity and performance of Golden- Gill, F.B. 1980. Historical aspects of winged Warblers (Vermivora chrysoptera) hybridization between Blue-winged and and Golden-winged x Blue-winged Warblers Golden-winged Warblers. Auk 97: 1-18. (V. pinus) hybrids at the leading edge of a Gill, F.B. 2004. Blue-winged Warblers hybrid zone. Behavioral Ecology and (Vermivora pinus) versus Golden-winged Sociobiology 61: 1797-1807. Warblers (V. chrysoptera). Auk 121:1014- Vallender, R., R.J. Robertson, V.L. Friesen and 1018. I.J. Lovette. 2007. Complex hybridization Gill, F.B. and B.G. Murray. 1972a. Song dynamics between Golden-winged and variation in sympatric Blue-winged and Blue-winged Warblers (Vermivora Golden-winged Warblers. Auk 89: 625-643. chrysoptera and Vermivora pinus) revealed Gill, F.B. and B.G. Murray. 1972b. by AFLP, microsatellite, intron and mtDNA Discrimination behavior and hybridization markers. Molecular Ecology 16: 2017–2029. of the Blue-winged and Golden-winged Will, T.C. 1986. The behavioral ecology of Warblers. Evolution 26: 282-293. species replacement: Blue-winged and Gill, F.B., R.A. Canterbury and J.L. Confer. Golden-winged warblers in Michigan. Ph. 2001. Blue-winged Warbler (Vermivora D. dissertation. University of Michigan, Ann pinus). In Birds of North America, No. 584. Arbor. http//bna.birds.cornell.edu.bnaproxy.birds.co Wood, N.A. 1951. The Birds of Michigan. MP rnell.edu/bna/species/584. 75. University of Michigan Museum of Highsmith, R.T. 1989. The singing behavior of Zoology. Ann Arbor, MI. Golden-winged Warblers. Wilson Bulletin 101:36-50. Suggested Citation McGowan, K.J. and K. Corwin, eds. 2008. The Second Atlas of Breeding Birds in New York Payne, R.B. 2010. Golden-winged Warbler State. Cornell University Press, Ithaca, NY. (Vermivora chrysoptera). In Chartier, A.T., Murray, B.G. and F.B. Gill. 1976. Behavioral J.J. Baldy, and J.M. Brenneman (eds.). 2010. interactions of Blue-winged and Golden- The Second Michigan Breeding Bird Atlas. winged Warblers. Wilson Bulletin 88: 231- Kalamazoo Nature Center. Kalamazoo, MI. 254. Accessed online at: Reed, L.P., R. Vallender and R.J. Robertson. . Warblers. Wilson Journal of Ornithology 119: 350-355. Sauer, J.R, J.E. Hines, and J. Fallon. 2008. The North American breeding bird survey, results and analysis 1966-2007. Version 5.15.2008. USGS Patuxent Wildlife Research Center. Laurel, MD. Shapiro, L.H., R.A. Canterbury, D.M. Stover and R.C. Fleischer. 2004. Reciprocal introgression between Golden-winged Warblers (Vermivora chrysoptera) and Blue-winged Warblers (V. pinus) in eastern North America. Auk 211: 1019-1030.