Breeding Habitat:Grassland
Nest Type:Open-cup nesting passerine
Migration Status:Short distance migrant
Nest Location:Ground-low nesting
Botteri's Sparrow is an occupant of subtropical grasslands whose breeding range barely enters the U.S. in south Texas and southeastern Arizona. This range extends south through Mexico to northeastern Nicaragua and northwestern Costa Rica (AOU 1983). Its preferred nesting habitats consist of dense grasses at least one foot tall, plus scattered bushes, fence posts, or other structures used for perches. In south Texas, breeding pairs are normally found in tall bunchgrass (Oberholser 1974). Arizona pairs are usually found in giant sacaton grass, but may have occupied other grassland habitats historically (Phillips et al. 1964).
This species was probably more widespread in southern Arizona during the nineteenth century, but there are relatively few records to document its original distribution in the state. Overgrazing during the 1880s and 1890s eliminated most suitable habitats, and probably significantly reduced the breeding population (Phillips et al. 1964). In south Texas, Botteri's Sparrow populations have experienced local declines during the twentieth century through the conversion of grasslands to cultivated fields and urban areas (Oberholser 1974). However, extensive suitable habitats remain in portions of its Texas range.
Except when the males are singing, this species tends to be secretive and easily overlooked. Given its very limited breeding range in the U.S., it has been recorded on fewer than 10 BBS routes. These limited data are insufficient to produce accurate trend estimates for this species.
During winter, most Botteri's Sparrows migrate from the U.S. into Mexico. They are rarely encountered on CBCs, and these sporadic records do not allow for estimation of population trends.
American Ornithologists Union. 1983. Check-list of North American
birds, 6th ed. Allen Press, Lawrence, KS. 877 pp.
Oberholser, H.C. 1974. The bird life of Texas, Vol. 2.
University of Texas Press, Austin, TX. 537 pp.
Phillips, A., J. Marshall, and G. Monson. 1964. The birds of
Arizona. Univ. of Arizona Press, Tucson, AZ. 212 pp.