Baltimore Oriole
Icterus galbula
Northern Orioles: These species, the Bullock’s Oriole and
Baltimore Oriole are very closely related and are sometimes merged as a single
species, Northern Oriole. Both are found in open broadleaf woods, foraging
among the leaves in trees.
The Baltimore Oriole shape like Bullock’s, but averages
slightly smaller. Some very drab females are difficult to distinguish from
Bullock’s.
Identification of Orioles: Bullock’s and Baltimore Orioles
are usually easily distinguished by plumage. 1st year male Bullock’s
develop a black throat by October and is subsequently easily identified. Female
Bullock’s varies little from the gary-bodies/yellow-ended pattern shown, but
female Baltimore is extremely variable. The drabbest pale female Baltimore is
most confusing, as it closely resembles Bullock’s female. Care study of the
head pattern reveals that on Baltimore the brightest color is on the breast
(usually tinged orange, unlike the paler yellow of Bullock’s), while on
Bullock’s the brightest color is on the malar; Baltimore has dusky-brown
auriculars washed with orange-yellow about the same color as the crown, while
Bullock’s has cleaner and brighter yellow auriculars and supercilium
contrasting with a dark eye-line and crown. Bullock’s tends to have broader
whitish edges on the greater coverts, mirroring the panel of adult males, and
pointed dark centers on the median coverts, creating a jagged border; Baltimore
has a straight border. Many Bullock’s Orioles have grayish undertail coverts,
unlike Baltimores. Not also that molt timing differs: Bullock’s molts later,
during or after fall migration (September-November); Baltimore molts on the
breeding grounds before migration (July-August). Hybrids and backcrosses are
fairly common where ranges overlap, creating a confusing array of intermediate
plumages. Only male hybrids are identifiable.
Voice: Song a short series of rich, clear, whistled, notes pidoo tewdi tewdi yewdi tew tidew; variable
in pattern, with pauses between each phrase; often gives simple two-note
whistle hulee and variations. Call is
a dry, harsh, uneven rattle. Flight call is husky, tinny, trumpeting veeet.
Works Cited
Sibley, D. A. The Sibley Guide to Birds. New
York City: Chanticleer Press, Inc. (2000): 519.
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