Sharp-tailed Sandpiper (Calidris acuminata)

Sharp-tailed Sandpiper

[order] CHARADRIIFORMES | [family] Scolopacidae | [latin] Calidris acuminata | [UK] Sharp-tailed Sandpiper | [FR] Becasseau a queue pointue | [DE] Spitzschwanz-Strandlaufer | [ES] Correlimos acuminado | [NL] Siberische Strandloper

Subspecies

Monotypic species

Physical charateristics

Similar in size and shape to the more common Pectoral Sandpiper, the rare Sharp-tailed Sandpiper can be distinguished by its rufous cap and distinctive white eye-line. Adults in breeding plumage are heavily spotted overall. Non-breeding plumage is lighter gray and less boldly streaked. Juveniles, the form most often seen in Washington, are redder than adults, with a buff-colored, lightly streaked breast, which often serves as their most distinctive field mark.
In areas where they are more abundant, Sharp-tailed Sandpipers are typically seen in large flocks. In Washington, they are often seen with Pectoral Sandpipers. They feed by moving steadily along in dense grass, heads down, picking up surface prey and probing lightly. They are seen on mudflats slightly more often than are Pectorals.

wingspan min.: 42 cm wingspan max.: 48 cm
size min.: 17 cm size max.: 20 cm
incubation min.: 19 days incubation max.: 23 days
fledging min.: 0 days fledging max.: 23 days
broods: 1   eggs min.: 3  
      eggs max.: 4  

Range

Eurasia : Northeast

Habitat

Sharp-tailed Sandpipers breed in wet Siberian tundra. During migration, they usually stop at grassy, coastal salt marshes, although they can also be found in coastal lagoons and mudflats, especially those adjacent to salt marshes.

Reproduction

Sharp-tailed Sandpipers are polygynous. Males with good territories mate with more than one female. Each female builds a nest out of grass on the wet, peaty tundra, or on a drier hummock. She incubates the clutch. After 19-23 days of incubation, the young hatch and leave the nest within a day or so. They find their own food immediately, but the female protects and tends them. The young birds begin to fly at 18-21 days.

Feeding habits

On their breeding grounds, Sharp-tailed Sandpipers eat primarily mosquito larvae. Other invertebrates, including mollusks and crustaceans, are also part of the diet.

Conservation

This species has a very 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). The population trend appears to be stable, and hence the species does not 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.
Sharp-tailed Sandpiper status Least Concern

Migration

Migratory. Leaves breeding grounds Jul-Sept. Main flyway via Transbaikalia, E of L Baikal, with smaller numbers in broad front from E Kazakhstan to Sea of Okhotsk; continues over E Mongolia and China, including Manchuria, to Japan, Korea, Philippines and New Guinea; probably overflies New Guinea during N migration. Juveniles on passage also occur regularly down Pacific coast and even into Alaska. Arrival in Australia Aug-Nov, and 25,000 birds arrived in single night mid-Sept 1984; birds leave S Australia early, mid-Feb to early Mar, undertaking rather prolonged N migration to breeding grounds, with series of short flights. Movements within Australia seem to be dispersive, with birds leaving when wetlands dry. Most of population migrates to Australia, mainly SE; few 1 st-year birds spend N summer in winter quarters.

Distribution map

Sharp-tailed Sandpiper distribution range map

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