Original description: Poospiza bellii var. nevadensis Ridgway 1873
Taxonomic history in AOU/AOS Check-list
AOU 1 (1886): Sage Sparrow, Amphispiza belli nevadensis
AOU 2 (1895): Sage Sparrow, Amphispiza belli nevadensis
AOU 3 (1910): Sage Sparrow, Amphispiza nevadensis nevadensis
AOU 4 (1931): Northern Sage Sparrow, Amphispiza nevadensis nevadensis
AOU 5 (1957): Sage Sparrow, Amphispiza belli nevadensis
AOU 6 (1983): Sage Sparrow, Amphispiza belli
AOU 7 (1998): Sage Sparrow, Amphispiza belli [nevadensis group]
IUCN Conservation Status: Of least concern
The rush to extract natural gas and other resources from the sagebrush plains of the Great Basin has imperiled a vast landscape and the plant and animal communities that occupy it; less than 10% of the region’s sagebrush steppe remains intact. Most attention has been paid to such large inhabitants of the cold desert as the pronghorn and the Greater Sage-Grouse, but sagebrush habitats are also home to many less conspicuous mammals, insects, and birds, including the Gray Flycatcher, Sage Thrasher, Green-tailed Towhee, Brewer Sparrow, and Sagebrush Sparrow, the populations of all of which are declining.
The Sagebrush Sparrow nests most commonly in salt desert scrub, the driest and most sparsely vegetated type of sagebrush habitat. It is listed as a species of special concern in Washington, and its status in Oregon is critical. Wyoming, with perhaps the greatest density of breeding Sagebrush Sparrows anywhere, lists the bird as a sensitive species.
In addition to disturbance and habitat destruction for energy development, agricultural conversion of sagebrush and urbanization have resulted in the local extirpation of Sagebrush Sparrows in both their breeding and their wintering ranges. The colonization of sagebrush steppe by non-native grasses, especially annual cheatgrass, is an increasing peril to this and other birds of the sage; extremely inflammable, cheatgrass allow fires to spread more frequently and more deeply into shrub steppe habitat, ultimately replacing the sagebrush ecosystem with alien grasses that tolerate and even exploit more frequent fire.
Behavior: Though less furtive than most Bell Sparrows—and frequenting more open habitats—the Sagebrush Sparrow can be difficult to see at the observer’s leisure. Most of these birds’ time is spent on the ground beneath sagebrush, saltbush, or overhanging mesquite twigs, walking or occasionally hopping in search of seeds and insects; it moves from cover to cover in low, fluttering flight, or runs, tail held high, across open stretches.
When Sagebrush Sparrows take a low perch atop a bush or tumbleweed, they continually flick the tail abruptly up, twitching like the second hand on a schoolhouse clock; that behavior is shared by the Bell Sparrow and, to a lesser extent, the Black-throated Sparrow. Males sing from a low perch, sometimes below the sparse canopy of the shrublands they inhabit.
Wintering Sagebrush Sparrows are found in small loose flocks, possibly family groups, often in association with Black-throated and Brewer Sparrows on saltbush flats. Feeding individuals in these flocks usually maintain a distance of several feet from one another.
Voice: The buzzy, low-pitched, strongly cadenced song of the Sagebrush Sparrow has moved even normally sober ornithologists to poetic flight. Robert Ridgway, best known today for his dry scientific descriptions of thousands of avian taxa, found the Sagebrush Sparrow singing as early as late February in Nevada:
“The song of this bird, although not brilliant in execution nor by any means loud, is nevertheless of such a character as to attract attention. It has a melancholy pensiveness, remarkably in accord with the dreary monotony of the surroundings, yet as a sort of compensation, is possessed of delicacy of expression and peculiar pathos—just as the fine lights and shadows on the sunlit mountains, combined with a certain vagueness in the dreamy distance, subdue the harsher features of the desert landscape.”
Even observers prone to less romantic a view of their surroundings can come to think of this sweet-voiced sparrow as the genius of its sadly vanishing loci.
Unlike the chippering warble of most Bell Sparrows, almost every note of the song of the Sagebrush Sparrow has an underlying buzz; some individuals can even recall a distant Blue Grosbeak. The song is variable in length, but usually follows an easily recognized and distinctive pattern: two or three short buzzing notes are followed by a somewhat longer buzzing trill, which gives way to two or three shorter notes introducing a distinctive slurred cadence. Any of the first elements—the introductory notes, the longer trill, or the following short notes—can be repeated, delaying the cadence. The song is continuous, without discernible pauses or phrasing, beebeebzzzbzabzazeerup. Volume and tone remain consistent through the song, and the only obvious emphasis is on the very last note, which can be a quite sharp chip.
The California Sparrow canescens appears to be capable of songs resembling that of the Sagebrush Sparrow; the song repertoire of that “confusing intermediate group” may in fact “grade clinally from nevadensis-like songs in the northeastern part of its range to belli-like songs in the south and west,” a circumstance that further complicates the field identification of that bird.
The flight calls of the Sagebrush Sparrow are high and metallic, almost junco-like, with the hint of a penetrating buzz; they are very short, with a harsh attack and virtually no audible decay. In flight, the calls may be even shorter and uttered in a quick series of up to ten notes, verging on a tremolo.
Detailed description and measurements drawn from standard reference works
Adult: Tail feathers dull blackish, with extensively white outer web and terminal spot on inner web. Upper tail coverts and rump ashy gray. Ground color of back and scapulars pale gray brown; well-defined dark shaft streaks extending across scapulars and center of back. Primaries and secondaries dull blackish with slightly paler gray edges; tertials darker, with broader gray-brown edges, fading to brownish white at tips. Greater coverts brownish black with narrow creamy brown edges and tips, in fresh plumage forming poorly defined, low-contrast wing bar. Median coverts blacker, with creamy brown tips, in fresh plumage forming inconspicuous wing bar. Marginal coverts of underwing very pale yellowish. Nape cold grayish.
Undertail coverts dull buffy white, brightening gradually into bright white of vent, belly, and breast. Sides of breast and flanks tinged pale buff, with coarse, irregular brownish shaft streaks. Central breast spot dark brown. Throat bright white, partially separated by fine, short lateral throat stripe from broad white jaw stripe; jaw stripe curls onto front of nape to set off gray ear coverts. Crown pale gray, with fine blackish shaft streaks. Short whitish supercilium begins above or just behind rear of narrow whitish eye ring and extends to base of bill above lore. Tarsus and toes dark pinkish brown. Bill blackish above, dull silvery blue below.
Juvenile: Tail feathers dull blackish, with narrow brown edges. Upper tail coverts, rump, back, and scapulars brown with narrow black shaft streaks. Primaries and secondaries dull blackish with slightly paler gray edges; tertials darker, with broader gray-brown edges, fading to brownish white at tips. Greater coverts brownish black with conspicuous buffy edges and tips. Median coverts blacker, with buffy tips. Nape dull brownish.
Undertail coverts buffy white, brightening gradually into dull brown-washed white of vent, belly, and breast. Breast and sides of breast with fine, irregular blackish streaks. Sides of breast and flanks pale yellowish buff, with irregular blackish shaft streaks. Throat dull white, bordered by faint or no pale brown lateral throat stripe; jaw stripe dull yellowish white. Crown dull gray with blackish shaft streaks. Short, narrow, poorly defined whitish supercilium begins at rear of narrow buffy eye ring and extends to base of bill above lore. Tarsus and toes pinkish brown. Bill blackish above, dull silvery blue below.
Length 147-150 mm (5.8-5.9 inches)
Wing chord 76-79 mm (3.0-3.1 inches)
Tail 71-75 mm (2.8-3.0 inches)
Mass 19 g