Breeds southern Canada (southern Alberta east to south-western Manitoba) and southern in Great Plains of USA (east to western Minnesota) to south-eastern New Mexico, northern Texas, western Oklahoma and central Kansas; has bred in wet years in eastern California. Non-breeding from south-eastern Utah and southern Arizona east to south-western Kansas, western Oklahoma and central and western Texas, southern in Mexico to southern Baja California, northern Sinaloa, Coahuila (uncommon), north-eastern Jalisco and central Tamaulipas.
 
Population
Estimated population is 27,000,000 (2010).
Lark Bunting (Calamospiza melanocorys) [XC172925]
by Richard E. Webster from CPER fields I - Pawnee Grasslands, Weld County, Colorado, United States (song)
Lark Bunting (Calamospiza melanocorys) [XC580986]
by Sue Riffe from Roggen, Weld County, Colorado, United States (song)
Subspecies
No subspecies.
Genus perhaps close to Chondestes, and in a clade that includes also Amphispiza and Spizella. Plumage dichromatism and elaborate aerial displays reminiscent of Chestnut-collared Longspur (Calcarius ornatus) and Rhynchophanes, but apparently not closely related.