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Many birders say the Golden-winged Warbler is
their favourite warbler. The species name chrysoptera is
Ancient Greek for "gold wing". The Carden Alvar is a great spot to
hear and see this attractive but vanishing warbler on its breeding
grounds.
HYBRIDS: Golden-winged and Blue-winged
Warblers hybridize freely. First-generation hybrids are called
“Brewster's Warblers” because they were originally considered a
separate species. Second and succeeding generation hybrids show
variations of both species, including a rare phenotype called the
“Lawrence’s Warbler”, also once considered a full species. In most
locations where both species persist and interbreed, Golden-winged
characteristics generally become “genetically swamped” by
Blue-winged characteristics. Thus, over time in one location, all
birds will appear to be Blue-wingeds even though many may have
Golden-winged ancestry. Blue-winged Warblers and hybrids are
increasing in Carden.
SONGS: The primary song of the
Golden-winged Warbler is a buzzy BEE-buz-buz-buz song. The Blue-winged’s
primary song is a wheezy Beee-Bzzz. Both species also have
secondary buzzy songs that are difficult to distinguish. Both
species and hybrids can sing any of the parental songs. Hybrid songs
are not intermediate in form. The Lawrence’s Warbler in Carden in
2018 sang like a Blue-winged.
HABITS: Singing Golden-wingeds often perch
in full view on a high bare or dead branch. The male's black mask
and bib combined with its habit of feeding upside down give it a
chickadee-like appearance. The black is replaced by grey in females.
HABITAT: Golden-winged Warblers nest in
dry or moist early successional scrubby habitats such as poplars or
alder thickets bordering woodlands that are used for foraging. Dead
trees are important singing posts.
CONSERVATION STATUS: The Golden-winged
Warbler is listed as Threatened in Canada by the Committee on
the Status of Endangered Wildlife in Canada (COSEWIC). Hybridization
is considered the main threat. Another threat is the loss of
breeding habitat due to forest regeneration. Habitat management that
mimics natural disturbances, such as periodic cuts and prescribed
burns, is needed to set back succession.
BEST PLACES: Do you daydream about hearing
and seeing Golden-winged Warblers on the breeding grounds? Reliable
spots are Wylie Road just south and just north of the Sedge Wren
Marsh. Also search other quiet roads on the Carden Alvar and nearby
southern edge of the Canadian Shield. Golden-wingeds are early
migrants and are on their breeding territories by mid-May. The best
time to hear and see them is mid-May to mid-June.
REFERENCE: Rondel, Emily. 2017. The
Golden-winged opportunist: A remarkable warbler and a century of
change in Ontario. OFO News 35(3): 4-5. See article in link:
http://www.ofo.ca/site/download/id/180
ACKNOWLEDGMENTS: I thank Michel Gosselin
and Emily Rondel for information and proofing, Terry Whittam for
information, and Jean Iron for the photo. |
