Small sandpiper with relatively long, droopy bill (longer on females). In breeding plumage, shows rich rufous tones on shoulders, cheeks, and crown. Nonbreeding is plain pale gray above and white below. Juveniles look pale-faced and have a bright strip of rufous feathers on the upper edge of the wings. Most similar to Semipalmated Sandpiper, which averages shorter-billed and duller grayish-brown overall. Extremely difficult to distinguish in winter; note Western is somewhat larger-headed and more front-heavy. Droopy bill might recall Dunlin, but Western is smaller and paler. Breeds on high Arctic tundra in Alaska. In migration and winter, occurs in large flocks on mudflats and beaches. Much more common in western North America; uncommon to rare on the east coast. Occurs in the winter in the U.S., unlike Semipalmated Sandpiper; regularly winters as far south as Peru, rare to Chile.