Lesser Sand Plover (Charadrius mongolus)

[order] CHARADRIIFORMES | [family] Charadriidae | [latin] Charadrius mongolus | [UK] Lesser Sand Plover | [FR] Pluvier de Mongolie | [DE] Mongolen-Regenpfeifer | [ES] Chorlitejo Mongol Chico | [NL] Kleine Woestijnplevier

This chunky plover is long-legged and long-billed. Breeding males have grey backs and white underparts. The breast, forehead and nape are chestnut, and there is a black eye mask. The female is duller, and winter and juvenile birds lack the chestnut, apart from a hint of rufous on the head. Legs are dark and the bill black.

Eurasia : Central, East

During the breeding season this species mainly occurs above the tree-line on mountains at altitudes of up to 5,500 m in the Himalayas. It inhabits barren valleys and basins in elevated tundra and mountain steppe, mainly near water (bogs) on moist but well-drained gravelly, rocky or sandy surfaces with sparse vegetation such as salt-pans, patches of detritus, dry edges of salt-marshes and places used by herds of cattle. In Siberia and the Commander (Komandorskiye) Islands the species also occurs at sea-level, here inhabiting sand dunes and shingle along the coast. The species is almost strictly coastal during the non-breeding season, preferring sandy beaches, mudflats of coastal bays and estuaries, sand-flats and dunes near the coast, occasionally frequenting mangrove mudflats (in Australia) and feeding on exposed coral reefs (Solomon Islands, Pacific). Very rarely the species also frequents coastal airfields, and during migration it may be seen on the shores of inland lakes (e.g. the East African Great Lakes) and rivers, or on cultivated land.

Mongolian Plovers breed discontinuously, in areas across east Asia from the Himalayas to North East Siberia, rarely in Alaska.

Like other plovers, Mongolian Plovers nest on the open ground, sometimes besides bushes or large stones. They dig shallow hollows, or use cattle footprints, and line these with pebbles or bits of plants. In the Himalayas, they nest above or beyond the tree-line, at altitudes of up to 5,500m. But in Siberia, on coastal shingle or sand dunes.

2-3 eggs are laid, and both parents incubate (22-24 days) and raise the young. But sometimes only the male raises the young. They fledge at 30-35 days.

The breeding diet of this species includes many beetles, weevils, fly larvae, stalk worms and crabs. During the non-breeding season this species takes insects, crustaceans (such as crabs and amphipods), molluscs (particularly bivalves) and polycheate worms.

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). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds 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.
It breeds above the tree line in the Himalayas and discontinuously across to bare coastal plains in north-eastern Siberia, with the Mongolian Plover in the eastern part of the range; it has also bred in Alaska. It nests in a bare ground scrape, laying three eggs. This species is strongly migratory, wintering on sandy beaches in east Africa, south Asia and Australasia. It is a very rare vagrant in western Europe, but, surprisingly, of the three individuals recorded in Great Britain up to 2003, one was a Mongolian Plover.
Like several other Asian shorebirds, Mongolian Plovers occur annually in the western Aleutian Islands, on islands in the Bering Sea, and on mainland Alaska. More rarely they appear as accidental stragglers elsewhere on the Pacific Coast of North America; there are also records for Alberta, Ontario, and Louisiana. It is quite possible that juveniles in their inconspicuous plumage may occur with greater frequency than records would indicate.

This species is fully migratory, with four definable groups migrating on a broad front to different wintering grounds. In central Siberia, flocks form in early July and depart for their winter quarters in early-August to early-September (adults leaving first), to arrive in India, south Arabia and East Africa in early-August to mid-September. Populations breeding in eastern Russia, Kamchatka, the Commander Islands and the Chukitsk Peninsula, winter from Taiwan to Australia, leaving their breeding grounds late-July to early-September. The population breeding in the Himalayas and southern Tibet winters in a range or areas from India to Sumatra, returning to its breeding grounds between late-February to April (reaching them between mid-April and mid-May). The fourth migratory group of this species breeds in eastern Tibet and winters from Thailand to the Greater Sundas. Many non-breeding birds may also stay in their winter quarters all year round. During the non-breeding season the species may occur singly or in flocks of up to 100 or more, but nesting pairs are solitary and territorial during the breeding season. This species is mainly diurnal but sometimes forages on moonlit nights.