Scientific Name: Vermivora chrysoptera
Nest Type: Cup
Nest Location: Ground
Clutch Size: 4-7; avg. 4-5
Food: Insects
Foraging Guild: Foliage gleaner
The Golden-winged Warbler is uncommon throughout most of its range in the
eastern United States. Although this species has been expanding its range northward and
eastward for the last century, it has concurrently disappeared from much of its southern
range. In this area it is apparently being displaced by its congener, the Blue-winged
Warbler (Gill 1980). It was placed on the Audubon Blue List in 1981 and 1982, and listed
as a species of special concern in 1986 (Tate 1986). Data collected in the USFWS
Breeding Bird Survey indicate that the Golden-winged Warbler population is stable across
the continent. However, there have been significant declines in the Great Lakes subregion
and in Wisconsin (Robbins et al. 1986). From 1966 to 1987, the species declined by 4.4%
per year in Wisconsin, and by 2% per year in Michigan and Minnesota (Hands et al. 1989).
Overall, there has been a 2.7% per year decline in the northcentral US between 1966 and
1987 (Hands et al. 1989). In Minnesota, the Golden-winged Warbler is now absent from
the southeastern portion of the state where it formerly bred. It is most common in the
central and north-central regions and appears to be expanding its range northward
(Janssen 1987).
The Golden-winged Warbler is a long distance migrant, wintering in Central America
and northern South America from Guatemala to Columbia (Ehrlich et al. 1988). The spring
migration period extends from early May to early June with a peak around May 10th. Fall
migration begins in late July and late individuals have been recorded into early October
(Janssen 1987).
The ecology and breeding biology of the Golden-winged Warbler is very similar to
that of its congener, the Blue-winged Warbler. It is insectivorous, gleaning and probing for
insects near the tops of shrubs and trees (Ficken and Ficken 1968). It nests in loose
colonies of up to 10 pairs, and its nest is placed on or near the ground where it is supported
and concealed by weed stalks. This species hybridizes with the Blue-winged Warbler
where the ranges overlap. Gill (1980) has shown there is a close temporal relationship
between the establishment of Blue-winged Warbler populations and the local extinction of
Golden-winged Warblers over the past 50 years. It may be that the Blue-winged Warbler
actually outcompetes the Golden-winged Warbler, or that genetic introgression of the
Golden-winged Warbler with the Blue-winged Warbler could account for the disappearance
of the Golden-winged Warbler (Gill 1980).
Confer and Knapp (1981) suggest that the Golden-winged Warbler is a habitat
specialist requiring early successional fields, while the Blue-winged Warbler is a habitat
generalist. In Tompkins County, New York, the Golden-winged Warbler nests only in the
shrub stage of successional habitat on large patches of abandoned farmland (Confer and
Knapp 1981). In this study, Golden-winged Warbler habitat was typified by a clumped
distribution of herbs and shrubs. According to Confer and Knapp (1981), succession on
clearcuts in central New York produces dense growths of saplings which are not suitable
habitat for these warblers. Only abandoned farmland produces the patchy early
successional habitat preferred by the Golden-winged Warbler. In contrast to these findings,
our data suggest that the Golden-winged Warbler tolerates a wide variety of habitat types in
Minnesota. Highest densities were recorded in sapling jack pines (about 3 pairs/40 acres),
and saw-sized balsam fir/aspen/paper birch (about 3 pairs/40 acres). Golden-winged
Warblers were also present in pole-sized jack pines, sapling, pole, and saw-sized aspen,
saw-sized white pine, and saw-sized elm/ash/maple stands (Hanowski and Niemi 1991b).
Kelleher (1967) also reported densities of 3 pairs per 40 acres in saw-sized aspen, and 2.5
pairs per 40 acres in saw-sized oak. Pfannmuller (1979) detected Golden-winged Warblers
most frequently in wetlands dominated by alders (about 8 pairs/40 acres), and in young
conifer plantations with dense growths of aspen and herbaceous vegetation (about 7
pairs/40 acres).
