This species is fully migratory (Snow and Perrins 1998). It arrives on the breeding grounds from mid-May to mid-June where it nests in solitary pairs and forages in small loose groups (Del Hoyo et al. 1996, Billerman et al. 2020, Snow and Perrins 1998).

The species breeds on Arctic coasts and in upland areas (Johnsgard 1981, Flint et al. 1984, Hayman et al. 1986), nesting close to the fringes of snow and ice, on wet moss or barren rocky tundra with patches of lichen and Dryas spp., on rocky islands and islets or on shingle beaches (Del Hoyo et al. 1996, Billerman et al. 2020). It forages on dry tundra or along the moist margins of ponds, at the edges of melting snow-drifts and in areas of thick moss (Hayman et al. 1986). During the winter and on passage the species shows a preference for tidal rocky shores with strong wave action and suitable high-tide roosting areas, often utilising artificial structures such as concrete sea defences and breakwaters (Del Hoyo et al. 1996, Billerman et al. 2020, Hayman et al. 1986). In some northern areas (e.g. Svalbard) the species frequents mudflats, shingle beaches and coastal lagoons before and after breeding but before migrating south (Del Hoyo et al. 1996, Billerman et al. 2020).

During the breeding season its diet consists largely of insects (e.g., adult, larval and pupal Diptera, Ichneumon wasps and aphids) and Collembola (springtails), as well as spiders, gastropods, annelid worms and some plant material (e.g. leaves, buds, berries and seeds) (Del Hoyo et al. 1996, Billerman et al. 2020). On the coast the species feeds predominantly upon molluscs (especially gastropods Littorina spp. and mussels Mytilus spp.) as well as insects (e.g. beetles and Diptera), small crustaceans (e.g. amphipods), annelid worms, small fish and algae (Enteromorpha spp.) (Del Hoyo et al. 1996, Billerman et al. 2020, Johnsgard 1981).

The nest is a small scrape positioned in the open on tundra moss, in hummocky tundra close to tufts of Dryas spp. or Arctostaphylos spp., or in rocky or pebbly areas between cliffs (Del Hoyo et al. 1996, Billerman et al. 2020, Johnsgard 1981, Flint et al. 1984).
In the high Arctic, the species typically breeds from sea level up to approximately 300 meters. In the low Arctic and subarctic regions, it primarily breeds inland on uplands, reaching elevations of over 1,000 meters in Sweden and Norway (Cramp and Simmons 1983).

C. maritima breeds throughout North America and northern Europe, occurring in the high arctic areas of Canada, Greenland (to Denmark), Iceland, in the northern parts of U.K., Norway (including Svalbard and Bear Island), Sweden, Finland, and northwest and central Siberia, coastal Murmansk, Franz Josef Land, Novaya Zemlya, Severnaya Zemlya, New Siberian Islands, Taimyr Peninsula, and northern Russia (Payne and Pierce 2020). In the non-breeding season, found in U.S.A., Greenland, Iceland, Norway, U.K., Ireland, Denmark (including Faroe Islands), France, north and west Germany, Netherlands, Sweden, and Belgium (Payne and Pierce 2020). Very rarely found in Spain and Portugal (including the Azores Islands) (Payne and Pierce 2020, eBird 2024).

Conservation Actions Underway
This species is not listed on the annexes of the European Union (EU) Birds Directive, but is covered by the general protection regime provided by Article 1 of the Directive to all naturally occurring wild species in the EU. It is listed on Annex II (strictly protected) of the pan-European Bern Convention, Annex II of the Convention on Migratory Species (CMS) and Annex II of the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA). Across the EU, 64 Natura 2000 sites have been designated for the conservation of this species on passage and in winter

Conservation Actions Proposed
The species requires greater protection from human disturbance and habitat degradation, including by the protection of more key wintering sites.