Sanderling Calidris alba Scientific name definitions

The Sanderling is a small, plump sandpiper, most commonly associated with sandy coastal beaches, which it occupies in winter and while on migration. When foraging on sandy beaches, Sanderlings move quickly, running ahead of incoming waves and chasing after receding ones, probing the sand for food. To a lesser extent, the species occupies sand- and mudflats, lagoons, and intertidal rocky shores.

Although its numbers are generally small locally, the Sanderling is a cosmopolitan bird during the non-breeding season. It may be found on almost any sandy beach, anywhere on the planet! During the nesting season, this bird occupies very different habitat: high-arctic tundra. Its breeding range is circumpolar, with highest numbers in the Canadian Arctic archipelago, Greenland, and high-arctic Siberia.

Sanderlings nest on the ground, typically in exposed, well-drained sites, either alone or in loose colonies. Mating systems appear to vary among populations, ranging from monogamy to serial polyandry. The extent and frequency of double-clutching and polyandry in this species have not been determined. The nest, a shallow scrape sparsely lined with leaves, typically contains 4 eggs. Both sexes incubate, brood, and attend to fledged offspring, although sexual roles depend on the mating system.

During winter, to varying degrees among populations, some individuals of either sex are strongly territorial in the intertidal zone and above the high tide of sandy beaches; otherwise individuals roam in conspecific, non-territorial flocks.

Research on the Sanderling has been focused largely on the nonbreeding season, and the most extensive work has been on foraging behavior, spacing, population structure (Myers et al. Myers et al. 1979b Myers, J. P., P. G. Connors and F. A. Pitelka. (1979b). Territory size in wintering Sanderlings: The effects of prey abundance and intruder density. Auk 96:551-561. Close , Myers et al. 1979a Myers, J. P., P. G. Conners, and F. A. Pitelka (1979a). Territoriality in non-breeding shorebirds. Studies in Avian Biology 2:231–246. Close , Myers et al. 1981 Myers, J. P., P. G. Connors and F. A. Pitelka. (1981). "Optimal territory size in the Sanderling: compromises in a variable environment." In Foraging behaviour: ecological, ethological, and psychological approaches., edited by A. C. Kamil and T. D. Sargent, 135-158. New York: Garland Press. Close ; Pitelka et al. 1980 Pitelka, F. A., J. P. Myers and P. G. Connors. (1980). Spatial and resource-use patterns in wintering shorebirds: the Sanderling in central coastal California. Proceedings of the International Ornithological Congress 17:1041-1044. Close ; Myers Myers 1981a Myers, J. P. (1981a). A test of three hypotheses for latitudinal segregation of the sexes in wintering birds. Canadian Journal of Zoology 59:1527-1535. Close , Myers 1983b Myers, J. P. (1983b). Space, time, and the pattern of individual associations in a group-living species: Sanderlings have no friends. Behavioral Ecology and Sociobiology 12:129-134. Close , Myers 1984 Myers, J. P. (1984). Spacing behavior of non-breeding shorebirds. In Shorebirds: Migration and Foraging Behavior (J. Burger and B. L. Olla, Editors). Plenum Press, New York, NY, USA. pp. 271–321. Close ), and physiology on migration and the wintering grounds (Castro et al. Castro et al. 1989 Castro, G., J. P. Myers and A. R. Place. (1989). Assimilation efficiency of Sanderlings (Calidris alba) feeding on horseshoe crab (Limulus polyphemus) eggs. Physiological Zoology 62:716-731. Close , Castro et al. 1992 Castro, G., J. P. Myers and R. E. Ricklefs. (1992). Ecology and energetics of Sanderlings migrating to four latitudes. Ecology 73 (3):833-844. Close ; Castro and Myers Castro and Myers 1990 Castro, G. and J. P. Myers. (1990). Validity of predictive equations for total body fat in Sanderlings from different nonbreeding areas. Condor 92:205-209. Close , Castro and Myers 1993 Castro, G. and J. P. Myers. (1993). Shorebird predation on eggs of horseshoe crabs during spring stopover on Delaware Bay. Auk 110:927-930. Close ).

Aspects of social behavior in winter have been well described. But, the Sanderling's mating system, population dynamics, and other aspects of the reproductive season are significantly understudied. Regional populations are in rapid decline, with the apparent cause being habitat degradation and increasing recreational use of sandy beaches.