[order] Passeriformes | [family] Hirundinidae | [latin] Riparia riparia | [UK] Sand Martin | [FR] Hirondelle de rivage | [DE] Uferschwalbe | [ES] Avión Zapador | [IT] Topino | [NL] Oeverzwaluw

Oeverzwaluw determination

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It has slender wings and a long, narrow, slightly forked tail that appears almost square in flight. Like other swallows, Sand Swallows have tiny feet and bills, although their bills are more conical than those of other swallows. They are brown above and slightly darker on the wings than on the back and rump. They have a distinct breast-band and white throat, with some white wrapping back to their ears. Juveniles look like adults.
Sand Swallows are usually seen in flocks, flying low over ponds and rivers. They usually forage in flight, but in severe weather they may forage on the ground. Their quick, fluttery wing-beats are more shallow and rapid than those of other swallows. These highly social birds nest in dense colonies of from 10 to 2,000 nests.

Usually found near water, Sand Swallows are closely associated with sandy, vertical banks along rivers and lakes or where a bank has been created by human excavation. Sand Swallows forage over water or open fields.

Riparia riparia is a widespread summer visitor to Europe, which accounts for less than a quarter of its global breeding range. Its European breeding population is very large (>5,400,000 pairs), but underwent a moderate decline between 1970-1990. Although declines continued in a number of countries during 1990-2000, the species was stable across most of Europe (the trend in Russia was unknown), and probably declined only slightly overall. Nevertheless, its population size remains far below the level that preceded its decline.
Bank Swallows adapt well to new surroundings and colonize areas quickly, necessary traits, since the banks in which they nest are often unstable and easily eroded.

Sand Swallows feed almost entirely on flying insects.

This species has a large range, with an estimated global Extent of Occurrence of 10,000,000 km². It has a large global population estimated to be 46,000,000 individuals (Rich et al. 2003). 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]

Sand Swallows are monogamous, although extra-pair copulations are common. These swallows use their tiny, conical bills and small feet to dig burrows in sandy banks. These banks are often not stable, and colonies move frequently because the banks collapse. The male generally digs the burrow, which can be up to five feet long. Deep inside the burrow, the female builds the nest of grass, rootlets, and weeds, lined with feathers. Both members of the pair incubate the 4 to 5 eggs for 14 to 16 days. Both feed the young, which leave the nest 18 to 24 days after hatching. The parents continue to feed the young for 3 to 5 days after they leave the nest.

Migratory; most of breeding range vacated in winter. Main west Palearctic populations plus all those of Siberia winter in African Sahel zone (from Sénégal eastwards) and in East Africa south to Mozambique. Extensive ringing, particularly in Britain and Ireland, has revealed much detail of movements within western Europe. During late summer and autumn, early-brood juveniles undertake local movements, which, by beginning of August, become oriented southwards; those leaving Britain choose short sea crossing. Passage of British and Irish birds continues SSW to Biscay coast of France and skirts north-west end of Pyrénées. Some birds then move down Ebro valley to Mediterranean coast of Spain, and others appear to move overland to Coto Doñana area. Birds cross Mediterranean into Morocco, reaching Sahel region by October or early November. In wintering areas, birds congregate where food available, which is often (but not always) associated with water. Appear to be nomadic, and ringing evidence from British birds suggests that many move east through Sahel region during winter to make their return northwards via Niger inundation zone (Mali) or further east. In a normal year, first arrivals in southern Britain occur well before end of March.