(Calidris alba; sometimes Crocethia alba), abundant shorebird, a worldwide species of sandpiper belonging to the family Scolopacidae (order Charadriiformes). Sanderlings nest on barrens near the sea around the North Pole, and they winter on sandy beaches virtually everywhere. About 20 cm (8 inches) long, sanderlings are rusty-backed in summer but are the whitest of sandpipers in winter. The long, white wing stripe is more showy than in other small species.