Purple Sandpiper (Calidris maritima)

[order] CHARADRIIFORMES | [family] Scolopacidae | [latin] Calidris maritima | [UK] Purple Sandpiper | [FR] Becasseau violet | [DE] Meer-Strandlaufer | [ES] Correlimos oscuro | [NL] Paarse Strandloper

Subspecies

Physical charateristics

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

Listen to the sound of Purple Sandpiper

[audio:http://www.aviflevoland.nl/sounddb/P/Purple Sandpiper.mp3]

Copyright remark: Most sounds derived from xeno-canto

Range

North America, Eurasia : North

Habitat

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 uplandsup 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.

Reproduction

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.

Feeding habits

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.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Migration

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.

Distribution map