| Species: Black-Throated Gray
Warbler Dendroica nigrescens
Description:
This is a striking black,
gray and white member of the ‘virens’ group’, 5 species which form a
closely related group of warblers. The other species which
compromise this group are the Golden-Cheeked, Black-Throated Green,
Townsend’s, and Hermit Warblers.
It is an elegant warbler of western North America found and first
described by John Kirk Townsend near Ft.William (Portland), Oregon.
The Black-Throated Gray was already known there as “Ah Kah a Qual”
by the Chinook.
It breeds generally west of the Rocky Mountains from northern Mexico
to British Columbia. First arrivals in sw B.C. are usually during
the second week of April.
Identification:
General: This is an averaged sized foliage-gleaning wood
warbler. It is 11-13 cm long and weighs 7-10 g.
Adult Male: Black
head, chin and throat, horizontal white line above eyes and below
cheeks; upper parts blue-gray; under parts white with black-streaked
sides; two white wing bars; tiny spot of bright yellow in front of
eyes(lores).
Adult female: Similar
to adult male but black of the head not as dark. The chin is always
white and most individuals have a white throat with a band of black
across the lower throat and a patch of black at the sides of the
rear throat. Yellow lores are not as bright yellow as males.
Juvenile: Black on
throat less solid than in adult male. Cheek varies from blackish to
slatey brown. Black of crown mostly restricted to sides, center of
crown gray. Yellow lores dull yellow.
Similar Species: The
general plumage of the males is almost identical to the Townsend’s
Warbler. The Townsend’s has greens and yellows rather than black and
white. Black and White Warblers may cause confusion, but all Black
and Whites show a median crown stripe and lack yellow lores.
Behavior: Watch the
Black-Throated Gray foraging, deliberately gleaning and reaching,
with occasional hover-gleaning and short sallies.
Habitat: Common in a
great variety of woodlands throughout its range, it is home in a
wide variety of semi-arid deciduous and conifer woodlands of the
western U.S. and southwestern B.C. Most foraging is at mid-level
within the canopy.
Information:
This bird tends to be
relatively tame and is often readily observed at close quarters as
it forages methodically among foliage. Nevertheless, little is known
about many aspects of its natural history.
It is a short-to-medium distance Neotropical migrant, and like many
such migrants, is insectivorous.
The nest is a deep, compact cup of plant fibers and grasses, bound
with spider webs and lined with fir, feathers, and hair. Nests are
often placed low (3-10ft.) in bushes, but frequently are placed at
20ft. or more well out on conifer limbs. There are usually 4 white
or cream-white, speckled brown eggs.
Conservation Status:
Black-Throated Gray Warbler
populations do not seem to have been affected by human activities to
any great extent, but changes are difficult to assess because so
little is known about this species.
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