Field Sparrow (Spizella pusilla) [XC154301]
by Jonathon Jongsma from Lower Moreland (near Huntingdon Valley), Montgomery, Pennsylvania, United States (flight call)
Field Sparrow (Spizella pusilla) [XC683447]
by William Whitehead from Ernest Oros Nature Preserve, Avenel, New Jersey, United States (flight call)
Subspecies
Sometimes considered sister to Worthen's Sparrow (Spizella wortheni) and has been considered conspecific, but more closely resembles Black-chinned Sparrow (Spizella atrogularis) in song and ecology, as well as bill colour. Subspecies intergrade broadly in Great Plains. Intermediate populations have been described as separate subspecies, perissura (described from Valentine, Nebraska) and vernonia (Japonica, Texas), but great variability of these intergrading populations makes taxonomic separation both inappropriate and unhelpful; both herein included within arenacea.
The following 2 subspecies are recognised:
arenacea (Wilson, 1810) - Breeds in central USA from south-eastern Montana and North Dakota south through Great Plains to north-eastern Colorado, western Oklahoma and central Texas. Non-breeding from Kansas, central Oklahoma, northern Arkansas and north-western Mississippi south to north-eastern Mexico (to northern Coahuila, central Nuevo León and Tamaulipas).
pusilla (Wilson, 1810) - Breeds in south-eastern Canada (southern Manitoba, southern Ontario and southern Quebec) and eastern USA from central Minnesota and central Michigan east to southern Maine, south to eastern Texas, south-eastern Louisiana, southern Mississippi, south-eastern Alabama and south-western Georgia, rarely to north-central Florida. Non-breeding from eastern Kansas, central Missouri, central Ohio, northern West Virginia, Maryland and southern Massachusetts south to southern Texas, Gulf Coast and central Florida.
BirdLife International Species Factsheet