White-rumped Sandpiper

Small to medium-sized sandpiper. Short neck. Moderately long straight bill. Moderately long legs. Long wings extend past end of tail on resting bird. Large white patch at base of tail. Underparts white, with fine dark streaks on pale gray breast. Black chevron marks on flanks in breeding plumage. Back mostly gray in nonbreeding plumage, mixed gray and warm brown in breeding plumage.