Habitat
Open fields of tall, dense grass and weeds, meadows and shrubby vegetation, especially in damp areas, dry upland prairies with small shrubs, and in the grassy understorey of open pinewoods.
Population
Estimated population is 79,000 (2010) and decreasing.
Status LC
Wetland draining and destruction of grassland habitat through fire suppression, conversion to agriculture or pine plantations and earlier and more frequent cutting of hayfields are the main threats.
For more information see BirdLife International Species Factsheet.
Henslow's Sparrow (Centronyx henslowii) [XC376459]
by Whitney Yoerger from Kentucky (near Richmond), Madison County, Kentucky, United States (song)
Henslow's Sparrow (Centronyx henslowii) [XC100910]
by Paul Marvin from Aaron Run Road, Garret County, Maryland, United States (song)
Subspecies
Genus, as currently delimited, is probably polyphyletic. Molecular studies suggest that present species is closely related to Baird's Sparrow (Passerculus bairdii) in a clade that includes also Melospiza, Passerculus and Xenospiza baileyi. Subspecies weakly differentiated.
Proposed subspecies houstonensis (based on a population that lived in Houston, in south-eastern Texas), probably inseparable from nominate, is now extinct.
The following 2 subspecies are recognised:
henslowii (Audubon, 1829) - Breeds from eastern South Dakota east through central Wisconsin and southern Canada (southern Ontario) to central New York, south to central Kansas, Missouri, Arkansas, northern Kentucky and central West Virginia. Winters in southern USA from central Texas east to South Carolina, south to Gulf Coast and northern Florida.
susurrans (Brewster, 1918) - Breeds from central New York east to southern New Hampshire, south to eastern West Virginia and eastern North Carolina. Winters along Usouthern coastal plain from South Carolina south to central Florida.
BirdLife International Species Factsheet