Sanderling

The sanderling, Calidris alba, is a small, dynamic wading bird, easily recognized by its plump form and stout bill. In non-breeding plumage, it presents a very pale, almost white appearance, save for a dark shoulder patch. Come summer, the bird's face and throat adopt a brick-red hue. Juveniles are more striking, with a spangled black and white pattern offering greater contrast.

Identification Tips

Adult sanderlings in breeding plumage can be confused with stints due to their size, but their stouter build and thicker bill are distinguishing features. In winter plumage, they might be mistaken for dunlins or red knots. However, the absence of a hind toe and their unique foraging behavior—characterized by a "bicycling" action of the legs—help in identifying them. In flight, a strong white wingbar is visible.

Habitat

During the breeding season, sanderlings favor the coastal tundra of the High Arctic, often selecting dry, stony areas near wetlands for nesting. In winter and during migration, they are most commonly found on coastal sandy beaches, as well as on tidal sand and mudflats, and less frequently on rocky shores.

Distribution

Sanderlings breed in the High Arctic regions of North America, Europe, and Asia, including the Canadian Arctic Archipelago, Greenland, Svalbard, and northern Russia. In winter, they are nearly cosmopolitan along the world's marine coasts, migrating long distances from the Arctic to as far as South America, South Europe, Africa, and Australia.

Behaviour

Sanderlings are highly gregarious outside the breeding season, often forming large flocks. They exhibit a distinctive foraging behavior, running along the shoreline, following the ebb and flow of waves, and rapidly probing the sand for prey.

Song & Calls

The sanderling's vocalizations are not extensively described here.

Breeding

On their Arctic breeding grounds, sanderlings lay 3-4 eggs in a ground scrape. The male may defend its territory aggressively, and pairings can be either monogamous or polyandrous. Their diet during this time includes insects and some plant material.

Similar Species

The sanderling can be differentiated from similar species by its lack of a hind toe and its distinctive foraging behavior.

Diet and Feeding

Sanderlings feed on invertebrates found in the sand, such as isopods and mole crabs. During spring migration, they are known to consume large numbers of horseshoe crab eggs in the Delaware Bay area.

Conservation status

The sanderling is currently listed as Least Concern by the IUCN, indicating that it is not at immediate risk of population decline or habitat loss at a global scale.