14-9-2015 CIUDAD DE ENCANTADA, CUENCA - EURASIAN NUTHATCH (Sitta europaea)

The Eurasian nuthatch or wood nuthatch (Sitta europaea) is a small passerine bird found throughout the Palearctic and in Europe. Like other nuthatches, it is a short-tailed bird with a long bill, blue-gray upperparts and a black eye-stripe. It is a vocal bird with a repeated loud dwip call. There are more than 20 subspecies in three main groups; birds in the west of the range have orange-buff underparts and a white throat, those in Russia have whitish underparts, and those in the east have a similar appearance to European birds, but lack the white throat.

Its preferred habitat is mature deciduous or mixed woodland with large, old trees, preferably oak. Pairs hold permanent territories, and nest in tree holes, usually old woodpecker nests, but sometimes natural cavities. If the entrance to the hole is too large, the female plasters it with mud to reduce its size, and often coats the inside of the cavity too. The six to nine red-speckled white eggs are laid on a deep base of pine or other wood chips.

The Eurasian nuthatch eats mainly insects , particularly caterpillars and beetles, although in autumn and winter its diet is supplemented with nuts and seeds. The young are fed mainly on insects, with some seeds, food items mainly being found on tree trunks and large branches. The nuthatch can forage when descending trees head first, as well as when climbing. It readily visits bird tables, eating fatty man-made food items as well as seeds. It is an inveterate hoarder, storing food year-round. Its main natural predator is the Eurasian sparrowhawk.

The Eurasian nuthatch's breeding range extends across temperate Eurasia from Great Britain (but not Ireland) to Japan. It is found between the 16–20 °C (61–68 °F) July isotherms, north to about latitude 64°N in western Russia and 69°N in Siberia. It breeds south to the Mediterranean in Europe, although it is absent from the islands, other than Sicily, and in most of Russia the southern boundary is around 54–55°N. In the east, the range includes most of China and Taiwan and much of Korea. It has occurred as a vagrant in Lebanon and the Channel Islands, and the nominate race has been recorded a few times in Finland where S. e. asiatica is the normal form.

Most populations are sedentary, apart from some post-breeding dispersal of young birds, and there is a reluctance to cross even short stretches of open water. Northern and eastern breeders are dependent on the cones of the Siberian stone pine, and if the crop fails many birds of the S. e. asiatica subspecies may move west into northern Sweden and Finland in autumn, sometimes staying to breed. Siberian S. e. arctica may make more limited movements south and east in winter, and S. e. amurensis, from southeast Russia, is regular in winter in Korea.

The preferred habitat is mature woodland with large, old trees, which provide extensive growth for foraging and nesting holes. In Europe, deciduous or mixed forest is favoured, particularly when containing oak. Parks, old orchards and other wooded habitats may be occupied as long as they have at least a 1 ha (2.5 acres) block of suitable trees. Particularly in mountains, old spruce and pine forests are used, and pine is also favoured in Taiwan. In most of Russia, conifers are used for nesting, but population densities are relatively low. Moroccan birds nest in oak, Atlas cedar and fir. Unusual habitats include dwarf juniper in Mongolia and rocky terrain in a limited part of southern Siberia.

The Eurasian nuthatch is primarily a lowland bird in the north of its range, but reaches the tree-line in Switzerland, at 1,200 m (3,900 ft) or higher, and breeds occasionally at 1,800–2,100 m (5,900–6,900 ft) in Austria. It breeds at similar levels in the mountains of Turkey, the Middle East and Central Asia. It is mainly a mountain bird in southern Japan, 760–2,100 m (2,490–6,890 ft), and Taiwan, 800–3,300 m (2,600–10,800 ft), but in southern China, the chestnut-vented nuthatch is the highland species, with the Eurasian species at lower levels.

Nuthatches are monogamous, and a pair occupies a breeding territory in which it spends the winter as well. Territory sizes range from 2–10 ha (5–25 acres) in Europe to an average of 30.2 ha (75 acres) in the sub-optimal conifer forests of Siberia. The male sings to defend his territory and attract a mate. Both sexes have a courtship display with a floating, quivering flight, and the male will also make circular flights with a spread tail and raised head. He will also feed the female while courting her. Despite the lifelong pairing, genetic research in Germany showed that at least 10% of the young in the study area were fathered by another male, usually from an adjacent territory.