Baird Sparrow, Centronyx bairdii

Original descriptionEmberiza Bairdii Audubon 1844

eBird range map

Taxonomic history at Avibase

Taxonomic history in AOU/AOSCheck-list

AOU 1 (1886): Baird’s Sparrow, Ammodramus bairdii

AOU 2 (1895): Baird’s Sparrow, Ammodramus bairdii

AOU 3 (1910): Baird’s Sparrow, Ammodramus bairdi

AOU 4 (1931): Baird’s Sparrow, Ammodramus bairdi

AOU 5 (1957): Baird’s Sparrow, Ammodramus bairdii

AOU 6 (1983): Baird’s Sparrow, Ammodramus bairdii

AOU 7 (1998): Baird’s Sparrow, Ammodramus bairdii

IUCN Conservation Status: Of least concern

Voice: The flight calls of the Baird Sparrow are very high, short, and thin tseeps, with almost no audible decay. Perched birds give a variety of lower-pitched chips, sometimes dry like a Lincoln Sparrow’s, sometimes fuller and more musical. The simple, beautiful song begins with several soft notes resembling the musical chip, followed by a light, loose trill; there may be a shift to a different pitch in the middle of the trill. At a distance, poorly heard Savannah Sparrows can sound similar. Males sing from tall grass stems or low shrubs; they usually perch near the top of vegetation, but may also sing from closer to or even on the ground. An infrequent flight display takes the male some ten feet in the air, where he utters several chips “followed by typical song with quivering wings on descent.” 

Behavior: Typically shy or very shy, Baird Sparrows spend most of their time on the ground beneath tall grasses, where they hop or shuffle in the hunt for seeds and invertebrates. When discovered by a human, they flex the ankles and crouch, apparently counting on the complex back pattern to hide them. 

Baird Sparrows are among the most stubbornly reluctant of grassland birds to fly, resembling some terrestrial quails in their fondness for the ground beneath dense cover. Birds fleeing danger are usually silent in flight; they do not swoop or dart, but fly straight ahead with little deviation. Baird Sparrows often land fairly close to the source of disturbance, but immediately disappear into the grass, and can usually be flushed again only with considerable effort.

Detailed description and measurements drawn from standard reference works

Adult: Tail feathers brown-gray, edged narrowly but conspicuously with creamy buff. Tail slightly notched. Rump feathers and upper tail coverts with brown centers, broadly edged with chestnut and off-white. Light brown upperparts conspicuously variegated with black and bright buff on back and scapulars. Primaries and secondaries dull brown-gray with broad paler tan edges, creating inconspicuous panel on folded wing. Tertials with black centers and white and chestnut edges. Greater and median coverts tan with blackish spots. Lesser coverts tan. Nape buffy orange with diffuse black streaking towards the sides. Underparts white with tan-tinged breast band and flanks. Flanks with chestnut-black streaks; tan breast band with scattered blackish streaks. White throat separated from pale tan jaw stripe by narrow, well-defined lateral throat stripe, usually appearing continuous with streaks of breast. Crown bright buff-orange, with broad black lateral stripes, breaking into fine streaks towards the nape. Pale ear coverts bordered below by short, poorly defined whisker; incomplete rear border takes the form of isolated spots. Very faint black eye line barely separates ear coverts from broad, buffy supercilium, which broadens in front of eye to include lore. Faint whitish eye ring. Bill pinkish brown above, paler below. Tarsi and toes dull pink. 

Juvenile: Similar to adult, but more intensely colorful above and more heavily marked below. (30) Blacker back more conspicuously scaled buffy. Wing coverts gray-black with broad buffy tips. 

Length 122-128 mm (4.8-5.0 inches)

Wing chord 68-72 mm (2.7-2.8 inches)

Tail 52-53 mm (2.0-2.1 inches)

W:T 1.8

Mass 17-20 g