[order] Charadriiformes | [family] Scolopacidae | [latin] Calidris maritima | [UK] Purple Sandpiper | [FR] Bécasseau violet | [DE] Meerstrandläufer | [ES] Correlimos oscuro | [IT] Piovanello violetto | [NL] Paarse Strandloper

Paarse Strandloper determination

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Males and females are similar in colour, slightly dimorphic in size. This species is seasonally dimorphic. In flight, the Purple Sandpiper has a narrow white wing-stripe and an all-dark tail. Breeding Adult has a crown tawny, streaked with black; back feathers edged with white and buff; breast and flanks white with blackish-brown speckling; belly white; bill long, slender, slightly downcurved, black with orange base; legs orange-yellow.
Winter Adult has head, neck, and upper breast dark greyish-brown; back feathers greyish-brown, with grey or whitish edges; flanks streaked and spotted grey-brown; bill and legs as in breeding adult. Juvenile crown tawny, lightly streaked with black; cheeks and nape buffy grey-brown; chin whitish; back feathers edged with whitish; breast and flanks white with blackish-brown speckling (tends to be sparse on flanks); bill and legs as in breeding adult

Rocky shores, from high-arctic islands and continental coasts through low-arctic and subarctic tundra, marginally overlapping boreal zone for breeding, and in winter shifting only far enough south to distribute entire population to areas clear of ice. In high Arctic breeds mainly from sea-level to c. 300 m; in low Arctic and subarctic more often on inland uplands¾up to 1300 m in Sweden and somewhat higher in southern Norway, tending to keep close to fringe of snow-clad or frozen ground.
Outside breeding season, closely attached to rocky islands, peninsulas, and other coastal sectors exposed to vigorous wave action and some tidal range.

Calidris maritima breeds in Greenland, Scandinavia and arctic Russia, with >75% of the global breeding range confined to Europe. The European breeding population is relatively small (<75,000 pairs), but appeared to be stable between 1970-1990. Trends were not available for the key populations in Greenland and Iceland during 1990- 2000, but the species was stable elsewhere.

Predominantly invertebrates; in breeding season at certain places and times also substantial amounts of plant material. Runs swiftly over seaweed and rocks uncovered by tide, and will even go under small waves. Snaps up items as tide retreats, dodging waves with agility and occasionally springing or fluttering into the air. Picks prey out of crevices in rocks and from between mussels. Occasionally wades in shallows. Turns over seaweed and debris to uncover prey.

This species has a large range, with an estimated global Extent of Occurrence of 1,000,000-10,000,000 km². It has a large global population estimated to be 170,000-220,000 individuals (Wetlands International 2002). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern. [conservation status from birdlife.org]

On the Faeroes and Iceland laying begins mid-May, in Spitsbergen main laying period second half June. In Russia main laying period mid-June to mid-July.Nestsite is on ground in the open. Nest is a small cup, diameter c. 10 cm, and depth 6 cm, often part-filled with small leaves of willow. Clutch size 3-4, one brood. Incubation lasts for 21-22 days. Fledging period unknown.

Migratory and sometimes partially migratory, but movements in various low Arctic and N temperate regions unclear. Non-breeding range extends further N than in other Calidris, to just below ice, e.g. SW Greenland, Finnmark and Murmansk, and S to Maryland (USA) and W France. Northernmost breeders fully migratory. Easternmost breeders migrate W to Murmansk or beyond. Unclear whether breeders at S of range are replaced by N breeders or N breeders show leap-frog migration, wintering S of S breeders. E Greenland breeders believed to winter in Iceland. Birds breeding in W Greenland winter in W & S Greenland. Ringing recoveries indicate migration between W Europe and Iceland, Greenland, Newfoundland and Baffin I, and between Norway and Britain. Post breeding migration later than in other Calidris species; females depart breeding grounds in advance of males and young, from Iceland in late Jun; males in Iceland until late Aug, and on Arctic islands from late Aug to mid-Sept. Arrival in North Sea and Iceland Oct-Nov. N movement Apr-May, and arrival in N breeding grounds mid-May to mid-Jun.