Plump, rock-loving shorebird with slightly droopy bill. Most often seen in nonbreeding plumage, which is fairly dark gray with heavily spotted underparts. Color of legs and base of bill varies from dull greenish to orangey. Breeding plumage shows reddish back and smudgy black belly. Juveniles show some rusty tones and have neat white fringes on wing feathers. Some variation across range; breeding population on Pribilof Islands in Alaska is larger and paler. Breeds on tundra; winters on rocky coastlines, sometimes feeding on mudflats. Typically in flocks in winter, often mixed with turnstones or Surfbird. Extremely similar to Purple Sandpiper but no range overlap.