impression that the tit's territory is more densely occupied than it actually is. Whether the theory is correct or not, those birds with large vocabularies are socially dominant and breed more successfully. Distribution, movements and habitat The great tit has a wide distribution across much of Eurasia. It can be found across all of Europe except for Iceland and northern Scandinavia, including numerous Mediterranean islands. In North Africa it lives in Morocco, Algeria and Tunisia. It also occurs across the Middle East, and parts of Central Asia from northern Iran and Afghanistan to Mongolia, as well as across northern Asia from the Urals as far east as northern China and the Amur Valley. The great tit occupies a range of habitats. It is most commonly found in open deciduous woodland, mixed forests, forest edges and gardens. In dense forests, including conifer forests it prefers forest clearings. In northern Siberia it lives in boreal taiga. In North Africa it rather resides in oak forests as well as stands of Atlas cedar and even palm groves. In the east of its range in Siberia, Mongolia and China it favours riverine willow and birch forest. Riverine woodlands of willows, poplars are among the habitats of the Turkestan subspecies, as well as low scrubland, oases; at higher altitudes it occupies habitats ranging from dense deciduous and coniferous forests to open areas with scattered trees. The great tit is generally not migratory. Pairs will usually remain near or in their territory year round, even in the northern parts of their range. Young birds will disperse from their parents' territory, but usually not far. Populations may become irruptive in poor or harsh winters, meaning that groups of up to a thousand birds may unpredictably move from northern Europe to the Baltic and also to Netherlands, Britain, even as far as the southern Balkans. The great tit was unsuccessfully introduced into the United States; birds were set free near Cincinnati, Ohio between 1872 and 1874 but failed to become established. Suggestions that they were an excellent control measure for codling moths nearly led to their introduction to some new areas particularly in the United States of America, however this plan was not implemented. A small population is present in the upper Midwest, believed to be the descendants of birds liberated in Chicago in 2002 along with European goldfinches, Eurasian jays, common chaffinches, European greenfinches, saffron finches, blue