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SAGEBRUSH BREWER'S SPARROW
Spizella breweri breweri
Family Fringillidae - Grosbeaks, Finches, Sparrows, and Buntings
Order Passeriformes
Risk Status
Official status
The Sagebrush Brewer's Sparrow is currently on British Columbia's Red
List (CDC = G5T4 S2).
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. Single
notes and alarm calls are also heard.
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. We have no information separating
the ranges of the
two subspecies in the United States. The Brewer's Sparrow lives south
through the western United States east of the Cascades south to eastern California, central
Arizona, and into northwestern New Mexico.
Habitat
This is a bird of open brushlands such as sagebrush plains, alpine meadows and valleys where low
shrubbery prevails. Sagebrush (Artemisia), in medium to high density, is the
preferred
habitat of the Sagebrush Brewer's Sparrow for nesting
and foraging for insects and weed seeds.
Ideally, the sagebrush
is located on southeast facing slopes.
Why is it endangered?
The main threat to the sparrow is the conversion of sagebrush land
to other uses. Removal of sagebrush habitat
to increase forage for cattle is a primary
limiting factor in
the distribution of the Sagebrush Brewer's Sparrow throughout
its range in
the Okanagan. As well, cattle may damage and/or disturb
nests and degrade foraging areas.
Range burning to remove sagebrush
affects species that require the shrubs for cover or food.
The
Brewer's Sparrow depends on sagebrush shrubs for nest sites.
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 close to the ground, usually less than a meter above it.
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, tootlets and weed stems lined with finer plant material and sometimes mammal hair.
The three to five eggs are bluish, variously speckled and marked in brown spots and scrawls. The
incubation period of the eggs in about 11 days with a nestling
period of about nine days. Nestling continues through June and
most late broods have fledged and foraging by mid-July.
Behaviour
The Sagebrush Brewer's Sparrow migrates, arriving on spring migration in late April
or early May, leaving 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 weed and grass seeds. As with many species of sparrow seasonal availability seems to determing 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
Living Landscape Directory of Researchers
and their
projects
Museum Specimens
this section sponsored by:
 Industry Canada
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