The sanderling (Calidris alba) is a small, plump, energetic wading bird. It has dark-spotted, rufous upperparts and breast, white underparts and black bill, legs and feet. Wings have conspicuous white stripes visible in flight. It feeds on crustaceans, molluscs, isopods, worms, plants and insects. The flight is swift and direct with rapid wing beats. Sexes are similar. The Sanderling is one of the world’s most widespread shorebirds. Though they nest only in the High Arctic, they occur on nearly all temperate and tropical sandy beaches throughout the world. The Ruddy Turnstone and the Whimbrel are the only other shorebirds that rival its worldwide distribution. This bird is similar in size to a dunlin, but stouter, with a thick bill. It shows a strong white wingbar in flight, and runs along the sandy beaches it prefers with a characteristic "bicycling" action of its legs, stopping frequently to pick small food items. The Sanderling has no hind toe, which gives it a distinctive running action.