Plainest swallow in North America. Plain brown above with indistinct brown wash across throat and breast. Wings are relatively broad; tail is short and square (or slightly notched). Juveniles have rusty wingbars. “Ridgway’s” subspecies, mainly found on the Yucatan peninsula, is larger and lankier, almost recalling a martin. Look for the deeper notch in the tail and dark-tipped undertail coverts. Often seen near water, sometimes in mixed flocks with other swallows. Breeds in holes and crevices, often along riverbanks or under a bridge. Not a colonial nester like Bank Swallow. Call is a low, grating buzz that rises slightly in pitch. Compare with Bank Swallow, which has a contrasting dark chest band. Also very similar to Southern Rough-winged Swallow, which overlaps in Central America. Southern Rough-winged has a brighter tawny throat and paler rump.