Original description: Zonotrichia botterii Sclater 1857
Taxonomic history in AOU/AOS Check-list
AOU 1 (1886): Arizona Sparrow, Peucaea arizonae; Mexican Sparrow, Peucaea mexicana
AOU 2 (1895): Arizona Sparrow, Peucaea arizonae; Mexican Sparrow, Peucaea mexicana
AOU 3 (1910):Botteri’s Sparrow, Peucaea botterii
AOU 4 (1931): Botteri’s Sparrow, Aimophila botterii botterii
AOU 5 (1957): Botteri’s Sparrow, Aimophila botterii botterii, Aimophila botterii texana
AOU 6 (1983): Botteri’s Sparrow, Aimophila botterii [botterii group, petenica group]
AOU 7 (1998): Botteri’s Sparrow, Aimophila botterii [botterii group, petenica group]
IUCN Conservation Status: Of least concern
Behavior: This is among the most furtive of the grassland sparrows, rarely seen well except when the males are singing. Nearly all foraging takes place on the ground beneath dense high grass or in the shade of short oaks or mesquites; feeding birds walk and hop on the ground, and, like other sparrows of open country, may run or walk when disturbed rather than fly.
When Botteri Sparrows do fly, their strong but shallow wing beats take them low above the grass and shrubs; the tail is often flirted and wagged. Landing is abrupt and graceless. Birds surprised into flight at close range often crash through the vegetation with irregular, noisy wing beats.
In the species’ northern range, males sing most of the summer, from May to August or September; in Arizona and Sonora, there is a noticeable increase in song during the monsoon season of late summer. Most songs are given from a conspicuous perch atop a low mesquite or other tree of shrub, where the male drops and slightly spreads the tail and throws the head back to open the bill. Singing in flight is frequent, but usually appears to be only incidental to the bird’s need to change location: a song begun at one perch is continued through the short flight to the next song post. Songs may also be commenced on a perch and completed on the ground or vice versa.
Voice: Most birders see their first Botteri Sparrow during the birds’ breeding season, when the male’s homely but cheerful rattling song renders visual identification secondary. The familiar primary song has three parts: a soft introduction; a long, dry tremolo; and a brief coda, sometimes omitted. The introduction comprises a series of two to six hesitant paired notes; each note pair is of a different quality, often two broad, smacking chirps followed by two short slurs: trp trp teew teew. The tremolo that follows is low-pitched and loose, with very little “musical” quality; it has been aptly compared to the end of a Black-chinned Sparrow song. The coda, given at a very low volume or not at all, is a short phrase of two or three downslurred whistles; unlike the tremolo, which is conspicuous from considerable distance, the introduction and coda are often inaudible to the human observer, who may see the bill open but hear nothing.
After the eggs have been laid, males may switch to a second song type, made up of “short, variable introductory notes, followed by trills and whistles… repeated… for up to several minutes without a gap between repetitions”; this performance may continue for more than ten seconds without pause, then be taken up again.
Botteri Sparrows often sing in flight, but they do not perform the stereotyped floating song flight of the Cassin Sparrow. Instead, Botteri Sparrows sing while flying between song perches or from a song perch to the ground.
When not singing, Botteri Sparrows are relatively quiet. They may give a stuttering chip’chip’chip when startled, or a soft, faintly metallic tik in alarm at the approach of a human observer. The usual contact call is a “piercing, high-pitched, ventriloquial seep,” lower-pitched and heavier than the corresponding see calls of Cassin Sparrows.
Detailed description and measurements drawn from standard reference works
Adult Peucaea botterii arizonae: Tail feathers dusky brown-gray with paler edges; central tail feathers with dark shaft streaks that intrude faintly onto webs in faint, indistinct barring. Upper tail coverts and rump dull rusty brown, feathers with darker shaft streaks. Back and scapulars reddish brown with dark chestnut to blackish shaft streaks; broad grayish edges in fresh plumage. Overall aspect broadly streaked above. Primaries dull brown gray, warmer brown on outer web. Secondaries dull brown gray with buffy to dull rusty edges and very inconspicuous buffy tips. Tertials dark dusky with broad buffy edges. Greater coverts dark brown with darker centers, broad dull rusty edges on outer web. Median coverts dark brown on inner web, almost entirely dull rusty on outer. Marginal coverts of under wing bright pale yellow. Nape gray with only very faint, sparse light reddish streaks.
Under tail coverts, vent, and flanks soft deep buff. Flank feathers with very narrow faintly darker shaft streaks, rarely creating transient impression of slight streaks. Center of belly and upper breast grayish white; lower breast buffy, created faint vested appearance. Throat buffy whitish, separated from buffy jaw stripe by very fine, short, usually incomplete rusty lateral throat stripe, often absent or invisible.
Crown reddish with broad gray feather edges and fine dark brown streaking; impression is often of plainer median area, more heavily streaked lateral area. Ear coverts soft grayish buff, bordered above by narrow rusty line behind eye. Broad supercilium gray behind eye, creamy buff in front of eye and on lore. Narrow white eye ring usually broken behind by rusty eye line and obscure at front of eye.
Short tarsus and toes dull pink. Thick-based, long, slightly downcurved bill bluish gray, darker on culmen.
Juvenile Peucaea botterii arizonae: Tail feathers blackish with paler edges; central tail feathers with deep black shaft streaks that intrude faintly onto webs in faint, indistinct barring. Upper tail coverts black, rump mottled buffy and dark brown. Back and scapulars dark brown with broad buffy edges. Overall aspect broadly streaked above. Primaries slaty with gray edges. Secondaries dull brown gray with buffy to dull rusty edges and very inconspicuous buffy tips. Tertials dark broad buffy edges. Greater coverts black with broad brown edges and buffy tips. Median coverts black with pale buffy edges. Marginal coverts of under wing pale yellow. Nape buffy with faint, sparse brown streaks.
Under tail coverts and vent deep buffy. Flanks, belly, and breast pale buffy. Breast and flanks with messy dark streaks. Throat pale buffy with light black spots and streaks. Dull whitish jaw stripe bordered below by faint blackish lateral throat stripe, above by blackish line behind eye.
Crown blackish with buffy feather edges. Ear coverts gray. Poorly defined supercilium gray behind eye, clearer and paler in front of eye and on lore. Narrow white eye ring bordered black below, at top of ear coverts.
Short tarsus and toes dull yellowish pink. Thick-based, long, slightly downcurved bill yellowish pink above, yellowish or pinkish below.
Length 132-161 mm (5.2-6.3 inches)
Wing 58-68 mm (2.3-2.7 inches)
Tail 59-73 mm (2.3-2.9 inches)
Mass 20-21 g