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SAGEBRUSH BREWER'S SPARROW
Spizella breweri breweri
Family Emberizidae - Sparrows, Towhees, Buntings
and Juncos
Order Passeriformes
Risk Status
Official status
The Sagebrush Brewer's Sparrow is currently on British Columbia's
Red List
(CDC = G5T4 S2B). COSEWIC
has assigned no official status priority.
Image Credits: photo taken by Steve
Cannings
Distinguishing features
Brewer's Sparrow is a small, slender, rather nondescript bird
about 12.7 cm to 13.7 cm long. Sexes are alike and are simply brownish-grey
above streaked in black. Below, they are greyish-white and unmarked.
The tail, long and notched, is brown, edged in grey. The wings bear
two faint whitish bars. Some individuals have faint streaking on
the sides. Young-of-the-year resemble adults but are streaked on
the sides with buffy overtones. Of the two geographic races of Brewer's
Sparrow, the northern one is somewhat darker and larger than the
one in the southern Okanagan. The Sagebrush Brewer's Sparrow's song
is a series of sustained (lasting up to ten seconds) and varied
bubbling notes and buzzy trills at different pitches. It may be
heard at anytime of the day during spring, summer and fall, and
often at night. The species is noted for its persistent singing,
and they also produce single notes and alarm calls.
Distribution
Map
Red dots indicate specimen records or confirmed breeding sites.
British Columbia
There are two geographic subspecies in British Columbia. Spizella
breweri breweri, the sagebrush subspecies, breeds in the Okanagan
and Similkameen Valleys south of Penticton. At the northern limit
of the species' range, Spizella breweri taverneri, the timberline
subspecies, migrates through the Okanagan to breed in northern British
Columbia and the southern Yukon; it also breeds in the mountains
of southeastern British Columbia to the International border.
North America
Elsewhere in Canada, the Sagebrush Brewer's Sparrow occurs in central
and southern Alberta and southwestern Saskatchewan. The Brewer's
Sparrow lives throughout the western United States east of the Cascades
south to eastern California, central Arizona, and into northwestern
New Mexico.
Habitat
This species inhabits open brushlands such as sagebrush plains,
alpine meadows and valleys where low shrubbery prevails. Sagebrush
(Artemisia), in medium to high density, is the typical habitat
of the Sagebrush Brewer's Sparrow for nesting and foraging. They
seem to frequent sagebrush on southeast facing slopes more than
other areas.
Why is it endangered?
The main threat to the sparrow is the conversion of sagebrush
land to other uses. Removal of sagebrush to increase forage for
cattle is a primary factor in the modern distribution of the Sagebrush
Brewer's Sparrow in the Okanagan. Cattle also can damage and/or
disturb nests and degrade foraging habitat for sparrows. Since Brewer's
Sparrow depends on sagebrush shrubs for nest sites and foraging
habitat, controlled fires to eliminate brush in cattle-country will
have obvious detrimental effects.
Use of insecticides for insect control may harm the birds directly
or through contamination or reduction of their prey species.
Biology
Breeding
The Sagebrush Brewer's Sparrow breeds in sagebrush habitat, whereas
the timberline subspecies breeds in tall willows, stunted conifers,
and dense clumps of birches. Both races have similar breeding habits,
building the nest less than a meter above the ground. The sparrow's
breeding density is about two pairs per hectare in typical habitat
at White Lake near Okanagan Falls. The nest is a cup made of coarse
grasses, rootlets and weed stems lined with finer plant material
and sometimes hair. Their three to five eggs are bluish and speckled
with brown spots and scrawls. The incubation
period of the eggs is about 11 days with a nestling period of about
nine days. Activity at the nest continues through June and most
late broods have fledged by mid-July.
Behaviour
The Sagebrush Brewer's Sparrow migrates, arriving on spring migration
in late April or early May, and leave the province on fall migration
in late August and early September.
Each singing male defends an area of about 0.5 hectare.
Diet or Growing requirements
The Sagebrush Brewer's Sparrow's diet consists of 50 percent or
more animal matter in summer when feeding young including: insects
such as beetles and their larvae, ants, wasps and grasshoppers.
In the fall and winter, they eat seeds. As with many species of
sparrow, seasonal food availability seems to determine whether animal
or vegetable matter predominates in the diet. Their daily water
requirement is obtained from their food.
Predators
No information is available at this time.
Sources of more information
Related On-line Sites to Visit
Publications
The Birds of British Columbia: Sparrows and Finches, Guiguet, 1982,
RBCM.
Our Living Legacy, 1993, RBCM
Birds of the Okanagan Valley, Cannings, 1987, p. 342.
The SOCAP Workshop Summary, The Nature Trust, 1989
Habitat Conservation Fund, August 1992
Museum Specimens
this section sponsored
by: 
Industry Canada
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