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Golden-winged Warbler
Vermivora chrysoptera
A petite songbird, the Golden-winged Warbler journeys thousands of miles between the New World tropics and North America in order to breed. Adapted to shrubby habitats, it thrived on our abandoned and overgrown farmlands a century ago. Its rapid decline since the 1980's cannot be explained solely by habitat loss, and that mystery has attracted many scientists to study this beautiful warbler.
Both sexes have a gray plumage overall, with light grey to grey-white underparts. Bright yellow adorns the male's crown and wings, and these patches are duller on the female. A black mask starts at the base of the male's bill and extends over the eyes into the ear patches, where it is largest. The chin, throat, and upper breast are jet black, forming a bib. On the female, the black areas are gray. This small songbird weighs about .31 ounces and measures about 4.75 inches long with a 7.5 inch wingspan.
The breeding range extends from northern Georgia northeastward through the Appalachian Mountains into western New England and southern Ontario west to northern Minnesota. Populations are most dense in north-central Minnesota and northern Wisconsin. The central part of this range (Illinois, Indiana, and Ohio) has been practically abandoned since the 19th Century. The breeding range appears to have expanded north- and northwestwards over the last 80 years. This warbler winters from central Guatemala southward into the northwestern tip of South America.
Breeding territories occur in shrubby habitats, often with scattered trees and at the edges of woods. Pastures, wetlands, stream sides, and the interface between forest and meadow are used. This warbler has colonized farmlands that are allowed to return to forest, in the early phases of succession when bushes and small trees dominate. In winter, a variety of moist and open to fairly open wooded habitats are used, usually at low to medium elevations.
By probing leaves and other small vegetative structures with its sharp bill, this songbird mainly consumes insects, especially moths and their larvae, and spiders. Wintering birds appear to prefer the lower canopy, 13-20 feet above ground. Specific studies on diet and feeding behavior are needed.
The male Golden-winged Warbler establishes a 1-14 acre territory, sometimes on the same site as he did the previous year. Females arrive a few days later and are chased by males and courted with singing, perched displays, and the "Moth Flight," characterized by slow speed and exaggerated wing beats. Females probably choose a spot for the nest, usually on the ground and often along the shaded edge of forest and field. The female stacks leaves and larger strips of vegetation, on which she then weaves a cup of finer plant strips. For about 11 days, she incubates 5 light pink or cream-colored eggs that are marked with delicate brown or dark purplish splotches and lines. Little is known about the development of the young, which are fed by both parents for about a month after they fledge. Sometimes, the adults separate the brood and tend one part on their own.
The Golden-winged Warbler visits North America to breed in summer and withdraws to the tropics in winter. In spring, males arrive a little before females, with most migrants arriving in the second and third weeks of May. Southbound migrants move in late summer at the end of August and the beginning of September.
Confer, J. L. 1992. Golden-winged Warbler (Vermivora chrysoptera). In The Birds of North America, No. 511 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
Sibley, David Allen. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.
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The Golden-winged Warbler has been in a serious, long-term decline at least since the mid-1960's. Recent losses have been especially acute. According to the Breeding Bird Survey, even areas that experienced a previous expansion, like northern New York, have seen significant declines: a 6.4% annual loss in New York between 1980 and 2006. For every year, on average, between 1966 and 2006, the decline has been 9.6% in Michigan, 9.2% in Pennsylvania, 10.2% West Virginia, and 2.1% in Wisconsin. Across its entire range during this period, the loss was 3.5% annually. Over the last 40 years, the Breeding Bird Survey has recorded a statistically significant increase nowhere. The Golden-winged Warbler is either extirpated or nearly extirpated in states like Massachusetts, Rhode Island, Connecticut, Georgia, New Jersey, and Illinois.
Over the last 150 years, the abandonment of American farms allowed this warbler's scrubland habitat to become abundant; but as the forests regrew, this habitat shrank. At the same time, urbanization and "clean" farming practices removed more shrublands, until the Golden-winged Warbler clung to remnants and powerline cuts, especially east of the Appalachian Mountains. These changes also brought the Golden-winged Warbler into contact with its very close relative, the Blue-winged Warbler. Competition for breeding habitat, interbreeding that favors the Blue-winged, and increased parasitism by the Brown-headed Cowbird have occurred. About 30% of Golden-winged Warbler nests are parasitized by cowbirds, which reduces fledging success by 17%.
In 2006, Canada designated the Golden-winged Warbler as Threatened. Connecticut, Georgia, Massachusetts, and Ohio consider it Endangered, while 9 other states list it as a conservation priority. It is regarded as Near Threatened by Birdlife International and a 2004 Watchlist Species by Partners in Flight. Its status in Central and South America is a concern, as more and more natural habitats are cut for agriculture and urban development.
The Cornell Lab of Ornithology is leading the Golden-winged Warbler Atlas Project, to better map its complex distribution and population shifts. States are beginning to manage and re-create its habitat. In 2003, Georgia burned 800 forested acres of the Chattahoochee National Forest on Chestnut Mountain for this warbler. Prescribed burns and selective timber harvest on Brawley Mountain appear to have contributed to the increase of Georgia's only breeding population, from 2 to as many as 12 pairs in 2005.
Control of the Blue-winged Warbler to favor the Golden-wing does not seem justified, especially because the Blue-winged is now experiencing range-wide declines, including areas where the species overlap. For example, in Connecticut between 1966 and 2006, the Blue-wing declined by an average 3.4% every year, as the Golden-wing slipped toward extirpation in that state. A similar pattern is occurring in West Virginia.
Buy shade-grown coffee, preferably farmed in the rustic tradition, which gives the Golden-winged Warbler a place to winter. Learn more about coffee production, history, ecology at Audubon and the American Birding Association's site, Shade Grown Coffee: A Glossary for Birders
Audubon's Important Bird Area program is an essential tool for the conservation of Golden-winged Warblers as well as other species.Learn how you canget involvedin the Important Bird Areas program.
Join the Cornell Lab of Ornithology's Golden-winged Warbler Atlas Project. From May to July, volunteer birders and professional biologists conduct point counts at known and potential breeding sites of Golden-winged Warblers.
Find out about actions you can take including Audubon programs and activities.
Learn more about this species and other birds through these resources.
Confer, J. L. 1992. Golden-winged Warbler ( Vermivora chrysoptera). In The Birds of North America, No. 511 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
Kraus, Nathan. "Golden-winged Warbler Conservation Effort in Georgia." The Citizen Scientist News Letter 1:1 (November 2005) pages 1-2. Georgia Department of Natural Resources. Accessed 31 August 2007
Sauer, J. R., J. E. Hines, and J. Fallon. 2006. The North American Breeding Bird Survey, DRAFT Results and Analysis 1966 - 2005. Version 6.2.2006. USGS Patuxent Wildlife Research Center, Laurel, MD. Accessed 31 August 2007.
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