Behaviour Although some populations of this species are sedentary or only disperse short distances (del Hoyo et al. 1996), most inland and northern coastal populations (Hayman et al. 1986) are fully migratory and have distinct separate breeding and wintering ranges (del Hoyo et al. 1996). The species occupies its breeding grounds chiefly from March to October (Hayman et al. 1986), dispersing from late-June immediately after the young fledge, with the southward migration peaking in September (del Hoyo et al. 1996). The species nests solitarily or in loose semicolonial groups (Johnsgard 1981, Urban et al. 1986, del Hoyo et al. 1996), usually in densities of 0.5 to 20 pairs per hectare (exceptionally up to 100 pairs per hectare) (Johnsgard 1981), and sometimes in association with other species (Powell and Collier 2000). Outside of the breeding season (Snow and Perrins 1998) the species feeds singly (MacKinnon and Phillipps 2000) or in small flocks of 20-30 individuals (del Hoyo et al. 1996, Snow and Perrins 1998), and occasionally in larger flocks of up to 260 individuals (Urban et al. 1986), often roosting in large mixed-species flocks (Urban et al. 1986). 

Habitat During all seasons the species is predominantly coastal (Johnsgard 1981, Hayman et al. 1986, del Hoyo et al. 1996) and is usually found on sand, silt or dry mud surfaces (del Hoyo et al. 1996), generally avoiding very exposed oceanic coastlines (Snow and Perrins 1998) and rocky or broken ground (del Hoyo et al. 1996). It also shows a preference for sparsely vegetated and sandy areas when breeding (Johnsgard 1981). Typical habitats include sandy, pebbly or muddy shores (Johnsgard 1981, Hayman et al. 1986, Grimmett et al. 1998), dunes (Johnsgard 1981), coastal lagoons (del Hoyo et al. 1996), coastal marshes (China) (MacKinnon and Phillipps 2000), tropical shores of coral limestone (Johnsgard 1981), estuaries and tidal mudflats (Africa) (Urban et al. 1986). It is uncommon on freshwater, even when migrating (Hayman et al. 1986), but frequently occurs on inland habitats not far from the coast such as seasonal watercourses (del Hoyo et al. 1996), open flats near brackish or saline lakes (Hayman et al. 1986, del Hoyo et al. 1996), salt-pans (del Hoyo et al. 1996, Grimmett et al. 1998), salty steppes with scattered grasses (Johnsgard 1981), sandy deserts (Johnsgard 1981), pebbly or muddy plains (Johnsgard 1981), gravel pits (del Hoyo et al. 1996), and less frequently sandy riverbanks (Africa) (Johnsgard 1981, Urban et al. 1986, Grimmett et al. 1998), sandy pond margins (Grimmett et al. 1998) and barren reservoir shores (Johnsgard 1981, del Hoyo et al. 1996). 

Diet Its diet consists mainly of insects and their larvae (Johnsgard 1981, del Hoyo et al. 1996) (e.g. beetles and flies) (del Hoyo et al. 1996), gammarids (Johnsgard 1981), crabs (Urban et al. 1986), other crustaceans (del Hoyo et al. 1996) and brine shrimps (Johnsgard 1981), bivalve and univalve molluscs (Johnsgard 1981, del Hoyo et al. 1996), polychaete worms (Johnsgard 1981, del Hoyo et al. 1996), spiders (del Hoyo et al. 1996) and small pieces of seaweed (Urban et al. 1986). 

Breeding site The nest is a shallow scrape (del Hoyo et al. 1996) positioned near water on bare earth or in sparse vegetation (del Hoyo et al. 1996), often on slightly raised ground (Snow and Perrins 1998) and partly sheltered by plants (Snow and Perrins 1998) or near conspicuous objects such as grass clumps or shrubs (Johnsgard 1981). The species nests in semicolonial groups, with nests spaced between 2 and 5 m (western Paleartic) (Snow and Perrins 1998) or more than 20 m apart (up to 80 m) (del Hoyo et al. 1996).

Conservation Actions Underway
The species is listed on Annex I of the EU Birds Directive and Annex II of the Bern Convention.

Conservation Actions Proposed
The following information refers to the species's European range only: Recreation at breeding sites needs to be controlled. Pollution of wetland habitats, land reclamation, infrastructure development and human disturbance at breeding sites needs to be stopped. Abandonment of salt pans should be reversed.