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The great tit ( Parus major) is a small passerine bird in the tit family Paridae. It is a widespread and common species throughout Europe, the Middle East, Central Asia and east across the Palearctic to the Amur River, south to parts of North Africa where it is generally resident in any sort of woodland; most great tits do not bird migration except in extremely harsh winters. Until 2005 this species was lumped with numerous other subspecies. DNA studies have shown these other subspecies to be distinct from the great tit and these have now been separated as two distinct species, the cinereous tit ( Parus cinereus) of southern Asia, and the Japanese tit ( Parus minor) of East Asia. The great tit remains the most widespread species in the genus Parus.
The great tit is a distinctive bird with a black head and neck, prominent white cheeks, olive upperparts and yellow underparts, with some variation amongst the numerous subspecies. It is predominantly insectivore in the summer, but will consume a wider range of food items in the winter months, including small hibernating bats. Like all tits it is a cavity nester, usually nesting in a hole in a tree. The female lays around 12 eggs and incubates them alone, although both parents raise the chicks. In most years the pair will raise two broods. The nests may be raided by woodpeckers, squirrels and least weasel and infested with , and adults may be hunted by sparrowhawks. The great tit has adapted well to human changes in the environment and is a common and familiar bird in urban parks and gardens. The great tit is also an important study species in ornithology.
The great tit was formerly treated as ranging from Britain to Japan and south to the islands of Indonesia, with 36 described subspecies ascribed to four main species groups. The major group had 13 subspecies across Europe, temperate Asia and north Africa, the minor group's nine subspecies occurred from southeast Russia and Japan into northern southeast Asia and the 11 subspecies in the cinereus group were found from Iran across south Asia to Indonesia. The three bokharensis subspecies were often treated as a separate species, Parus bokharensis, the Turkestan tit. This form was once thought to form a ring species around the Tibetan Plateau, with gene flow throughout the subspecies, but this theory was abandoned when sequences of mitochondrial DNA were examined, finding that the four groups were distinct (monophyly) and that the hybridisation zones between the groups were the result of secondary contact after a temporary period of isolation.
A study published in 2005 confirmed that the major group was distinct from the cinereus and minor groups and that along with P. m. bokharensis it diverged from these two groups around 1.5 million years ago. The divergence between the bokharensis and major groups was estimated to have been about half a million years ago. The study also examined hybrids between representatives of the major and minor groups in the Amur River where the two meet. Hybrids were rare, suggesting that there were some reproductive barriers between the two groups. The study recommended that the two eastern groups be split out as new species, the cinereous tit ( Parus cinereus), and the Japanese tit ( Parus minor), but that the Turkestan tit be lumped in with the great tit. This taxonomy has been followed by some authorities, for example the . The Handbook of the Birds of the World volume treating the Parus species went for the more traditional classification, treating the Turkestan tit as a separate species but retaining the Japanese and cinereous tits with the great tit, a move that has not been without criticism.
The nominate subspecies of the great tit is the most widespread, its range stretching from the Iberian Peninsula to the Amur Valley and from Scandinavia to the Middle East. The other subspecies have much more restricted distributions, four being restricted to islands and the remainder of the P. m. major subspecies representing former glacial refuge populations. The dominance of a single, morphologically uniform subspecies over such a large area suggests that the nominate race rapidly recolonised a large area after the last Ice age. This hypothesis is supported by genetic studies which suggest a geologically recent genetic bottleneck followed by a rapid population expansion.
The genus Parus once held most of the species of tit in the family Paridae, but morphological and genetic studies led to the splitting of that large genus in 1998. The great tit was retained in Parus, which along with Cyanistes comprises a lineage of tits known as the "non-hoarders", with reference to the hoarding behaviour of members of the other clade. The genus Parus is still the largest in the family, but may be split again. Other than those species formerly considered to be subspecies, the great tit's closest relatives are the White-naped tit and green-backed tit tits of southern Asia. Hybrids with tits outside the genus Parus are very rare, but have been recorded with blue tit, coal tit, and probably marsh tit. (1996). 9780713639643, Christopher Helm. ISBN 9780713639643
There is some variation in the subspecies. P. m. newtoni is like the nominate race but has a slightly longer bill, the mantle is slightly deeper green, there is less white on the tail tips, and the ventral mid-line stripe is broader on the belly. P. m. corsus also resembles the nominate form but has duller upperparts, less white in the tail and less yellow in the nape. P. m. mallorcae is like the nominate subspecies, but has a larger bill, greyer-blue upperparts and slightly paler underparts. P. m. ecki is like P. m. mallorcae except with bluer upperparts and paler underparts. P. m. excelsus is similar to the nominate race but has much brighter green upperparts, bright yellow underparts and no (or very little) white on the tail. P. m. aphrodite has darker, more olive-grey upperparts, and the underparts are more yellow to pale cream. P. m. niethammeri is similar to P. m. aphrodite but the upperparts are duller and less green, and the underparts are pale yellow. P. m. terrasanctae resembles the previous two subspecies but has slightly paler upperparts. P. m. blandfordi is like the nominate but with a greyer mantle and scapulars and pale yellow underparts, and P. m. karelini is intermediate between the nominate and P. m. blandfordi, and lacks white on the tail. The plumage of P. m. bokharensis is much greyer, pale creamy white to washed out grey underparts, a larger white cheep patch, a grey tail, wings, back and nape. It is also slightly smaller, with a smaller bill but longer tail. The situation is similar for the two related subspecies in the Turkestan tit group. P. m. turkestanicus is like P. m. bokharensis but with a larger bill and darker upperparts. P. m. ferghanensis is like P. m. bokharensis but with a smaller bill, darker grey on the flanks and a more yellow wash on the juvenile birds.
colour of the male bird's breast has been shown to correlate with stronger sperm, and is one way that the male demonstrates his reproductive superiority to females. Higher levels of carotenoid increase the intensity of the yellow of the breast its colour, and also enable the sperm to better withstand the onslaught of free radicals. Carotenoids cannot be synthesized by the bird and have to be obtained from food, so a bright colour in a male demonstrates his ability to obtain good nutrition. However, the saturation of the yellow colour is also influenced by environmental factors, such as weather conditions. The width of the male's ventral stripe, which varies with individual, is selected for by females, with higher quality females apparently selecting males with wider stripes.
One explanation for the great tit's wide repertoire is the Beau Geste hypothesis. The eponymous hero of the novel propped dead soldiers against the battlements to give the impression that his fort was better defended than was really the case. Similarly, the multiplicity of calls gives the 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. (2025). 9780701169077, Chatto & Windus. ISBN 9780701169077
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 pinophyta 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 Arecaceae 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 Shrubland, Oasis; 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 bird migration. 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 states 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 between 1872 and 1874 but failed to become established. Suggestions that they were an excellent control measure for 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, , , European greenfinches, , and , although sightings of some of these species pre-date the supposed introduction date. Birds were introduced to the Almaty Province in what is now Kazakhstan in 1960–61 and became established, although their present status is unclear.
Large food items, such as large seeds or prey, are dealt with by "hold-hammering", where the item is held with one or both feet and then struck with the bill until it is ready to eat. Using this method, a great tit can get into a hazelnut in about twenty minutes. When feeding young, adults will hammer off the heads of large insects to make them easier to consume, and remove the gut from caterpillars so that the in the gut will not retard the chick's growth.
Great tits combine dietary versatility with a considerable amount of intelligence and the ability to solve problems with insight learning, that is to solve a problem through insight rather than trial and error. In England, great tits learned to break the foil caps of milk bottles delivered at the doorstep of homes to obtain the cream at the top. This behaviour, first noted in 1921, spread rapidly in the next two decades. In 2009, great tits were reported killing, and eating the brains of roosting pipistrellus bats. This is the first time a songbird has been recorded preying on bats. The tits only do this during winter when the bats are hibernating and other food is scarce. They have also been recorded using tools, using a conifer in the bill to extract larvae from a hole in a tree.
Great tits are cavity nesters, breeding in a hole that is usually inside a tree, although occasionally in a wall or rock face, and they will readily take to . The nest inside the cavity is built by the female, and is made of plant fibres, grasses, moss, hair, wool and feathers. The number in the clutch is often very large, as many as 18, but five to twelve is more common. Clutch size is smaller when birds start laying later, and is also lower when the density of competitors is higher. Second broods tend to have smaller clutches. Insularity also affects clutch size, with great tits on offshore islands laying smaller clutches with larger eggs than mainland birds. The eggs are white with red spots. The female undertakes all avian incubation duties, and is fed by the male during incubation. The bird is a close sitter, hissing when disturbed. The timing of hatching, which is best synchronised with peak availability of prey, can be manipulated when environmental conditions change after the laying of the first egg by delaying the beginning of incubation, laying more eggs or pausing during incubation. The incubation period is between 12 and 15 days.
The chicks, like those of all tits, hatch unfeathered and blind. Once feathers begin to erupt, the nestlings are unusual for altricial birds in having plumage coloured with similar to their parents (in most species it is dun-coloured to avoid predation). The nape is yellow and attracts the attention of the parents by its ultraviolet reflectance. This may be to make them easier to find in low light, or be a signal of fitness to win the parents' attention. This patch turns white after the first moulting at age two months, and diminishes in size as the bird grows.
Chicks are fed by both parents, usually receiving of food a day. Both parents provision the chicks with food and aid in nest sanitation by removing faecal packets, with no difference in the feeding effort between the sexes. The nestling period is between 16 and 22 days, with chicks being independent of the parents eight days after fledge. Feeding of the fledgling may continue after independence, lasting up to 25 days in chicks from the first brood, but as long as 50 days in the second brood. Nestlings from second broods have weaker immune systems and body condition than those from first broods, and hence have a lower juvenile survival rate.
Inbreeding depression occurs when the offspring produced as a result of a mating between close relatives show reduced fitness. The reduced fitness is generally considered to be a consequence of the increased expression of deleterious recessive alleles in these offspring. In natural populations of P. major, inbreeding is avoided by dispersal of individuals from their birthplace, which reduces the chance of mating with a close relative.
The great tit has generally adjusted to human modifications of the environment. It is more common and has better breeding success in areas with undisturbed forest cover, but it has adapted well to human-modified habitats, and can be urban wildlife. For example, the breeding population in the city of Sheffield (a city of half a million people) has been estimated at some 17,000 individuals. In adapting to human environments its song has been observed to change in noise-polluted urban environments. In areas with low frequency background noise pollution, the song has a higher frequency than in quieter areas. This tit has expanded its range, moving northwards into Scandinavia and Scotland, and south into Israel and Egypt. The total population is estimated at between 300 and 1,100 million birds in a range of 32.4 million km2 (12.5 million sq mi). While there have been some localised declines in population in areas with poorer quality habitats, its large range and high numbers mean that the great tit is not considered to be threatened, and it is classed as least concern on the IUCN Red List.
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