Gorrión Molinero

Identificación

The Eurasian tree sparrow is .mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);clip-path:polygon(0px 0px,0px 0px,0px 0px);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px}12.5–14 cm (5–5+1⁄2 in) long, with a wingspan of about 21 cm (8.3 in) and a weight of 24 g (0.85 oz), making it roughly 10% smaller than the house sparrow. The adult's crown and nape are rich chestnut, and there is a kidney-shaped black ear patch on each pure white cheek; the chin, throat, and the area between the bill and throat are black. The upperparts are light brown, streaked with black, and the brown wings have two distinct narrow white bars. The legs are pale brown, and the bill is lead-blue in summer, becoming almost black in winter.<p>This sparrow is distinctive even within its genus in that it has no plumage differences between the sexes; the juvenile also resembles the adult, although the colours tend to be duller. Its contrasting face pattern makes this species easily identifiable in all plumages; the smaller size and brown, not grey, crown are additional differences from the male house sparrow. Adult and juvenile Eurasian tree sparrows undergo a slow complete moult in the autumn, and show an increase in body mass despite a reduction in stored fat. The change in mass is due to an increase in blood volume to support active feather growth and a generally higher water content in the body.<p>The Eurasian tree sparrow has no true song, but its vocalisations include an excited series of tschip calls given by unpaired or courting males. Other monosyllabic chirps are used in social contacts, and the flight call is a harsh teck. A study comparing the vocalisations of the introduced Missouri population with those of birds from Germany showed that the US birds had fewer shared syllable types (memes) and more structure within the population than the European sparrows. This may have resulted from the small size of the founding North American population and a consequent loss of genetic diversity.

Taxonomía

The Old World sparrow genus Passer is a group of small passerine birds that is believed to have originated in Africa, and which contains 15–25 species depending on the authority. Its members are typically found in open, lightly wooded, habitats, although several species, notably the house sparrow (P. domesticus) have adapted to human habitations. Most species in the genus are typically 10–20 cm (3.9–7.9 in) long, predominantly brown or greyish birds with short square tails and stubby conical beaks. They are primarily ground-feeding seed-eaters, although they also consume invertebrates, especially when breeding. The Eurasian species is not closely related to the American tree sparrow (Spizelloides arborea), which is in a different family, the New World sparrows.<p>The Eurasian tree sparrow's binomial name is derived from two Latin words: passer, "sparrow", and montanus, "of the mountains" (from mons "mountain"). The Eurasian tree sparrow was first described by Carl Linnaeus in his 1758 Systema Naturae as Fringilla montana, but, along with the house sparrow, it was soon moved from the finches (family Fringillidae) into the new genus Passer created by French zoologist Mathurin Jacques Brisson in 1760. The Eurasian tree sparrow's common name is given because it prefers tree holes for nesting. This name, and the scientific name montanus, do not appropriately describe this species's habitat preferences: the German name Feldsperling and the Hungarian name mezei veréb ("field sparrow") comes closer to doing so.<p>This species varies little in appearance across its large range, and the differences between the seven extant subspecies recognised by Clement are slight. At least 15 other subspecies have been proposed, but they are considered to be intermediates of the listed subspecies.

Nombre científico

Passer montanus

Autoridad

(Linnaeus, 1758)

Orden

Passeriformes

Familia

Pásridos

Género

Passer

Distribución y hábitat

The Eurasian tree sparrow's natural breeding range comprises most of temperate Europe and Asia south of about latitude 68°N (north of this the summers are too cold, with July average temperatures below 12 °C (54 °F)) and through Southeast Asia to Java and Bali. It formerly bred in the Faroes, Malta and Gozo. In South Asia it is found mainly in the temperate zone. It is sedentary over most of its extensive range, but northernmost breeding populations migrate south for the winter, and small numbers leave southern Europe for North Africa and the Middle East. The eastern subspecies P. m. dilutus reaches coastal Pakistan in winter and thousands of birds of this race move through eastern China in autumn.<p>The Eurasian tree sparrow has been introduced outside its native range but has not always become established, possibly due to competition with the house sparrow. It was introduced successfully to Sardinia, eastern Indonesia, the Philippines and Micronesia, but introductions to New Zealand and Bermuda did not take root. Ship-carried birds colonised Borneo. This sparrow has occurred as a natural vagrant to Gibraltar, Tunisia, Algeria, Egypt, Israel, the United Arab Emirates, Morocco and Iceland.In North America, a population of about 15,000 birds has become established around St. Louis and neighbouring parts of Illinois and southeastern Iowa. These sparrows are descended from 12 birds imported from Germany and released in late April 1870 as part of a project to enhance the native North American avifauna. Within its limited US range of about 22,000 square kilometres (8,500 sq mi), the Eurasian tree sparrow has to compete with the house sparrow in urban centres, and is therefore mainly found in parks, farms and rural woods. The American population is sometimes referred to as the "German sparrow", to distinguish it from both the native American tree sparrow species and the much more widespread "English" house sparrow.<p>In Australia, the Eurasian tree sparrow is present in Melbourne, towns in central and northern Victoria and some centres in the Riverina region of New South Wales. It is a prohibited species in Western Australia, where it often arrives on ships from Southeast Asia.<p>Despite its scientific name, Passer montanus, this is not typically a mountain species, and reaches only 700 m (2,300 ft) in Switzerland, although it has bred at 1,700 m (5,600 ft) in the northern Caucasus and as high as 4,270 m (14,010 ft) in Nepal. In Europe, it is frequently found on coasts with cliffs, in empty buildings, in pollarded willows along slow water courses, or in open countryside with small isolated patches of woodland. The Eurasian tree sparrow shows a strong preference for nest-sites near wetland habitats and avoids breeding on intensively managed mixed farmland.<p>When the Eurasian tree sparrow and the larger house sparrow occur in the same area, the house sparrow generally breeds in urban areas while the smaller Eurasian tree sparrow nests in the countryside. Where trees are in short supply, as in Mongolia, both species may utilise man-made structures as nest sites. The Eurasian tree sparrow is rural in Europe, but is an urban bird in eastern Asia; in southern and central Asia, both Passer species may be found around towns and villages. In parts of the Mediterranean, such as Italy, both the tree and the Italian or Spanish sparrows may be found in settlements. In Australia, the Eurasian tree sparrow is largely an urban bird, and it is the house sparrow which utilises more natural habitats.

Área de cría

PAL, OR : subarctic to tropics of Palearctic and Oriental regions in farms, parks, cities: British Is., s Scandinavia, se Murmansk e to s Chukotka, Kamchatka, and Commander Is. (nw to ne Russia), in s to Iberian Pen., Gran Canaria (c Canary Is., Macaronesia, w of n Africa), Mediterranean is. through Turkey, n Iran, sc Pakistan, Tibet, c, e Himalayas through se Asia, e Asian is. from Kuril Is., all Japan, Taiwan, all Philippines and Indonesian Arch.; introduced many other places

Área no reproductiva

short-distance wandering

Migración

Especie residente

Comportamiento

Patrón migratorio: Especie residente.

Conservación

Tendencia poblacional: en declive.

Tendencia poblacional

en declive