Long-tailed tit

The long-tailed tit was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Parus caudatus. The current genus name Aegithalos was a term used by Aristotle for some European tits, including the long-tailed tit. The specific epithet caudatus is the Latin word for "tailed". Linnaeus did not invent this Latin name. "Parus caudatus" had been used by earlier authors such as the Swiss naturalist Conrad Gessner in 1555, the Italian naturalist Ulisse Aldrovandi in 1599, and the English ornithologist Francis Willughby in 1676. Willughby listed the English name as the "long tail'd titmouse". Its previous common nickname in everyday English was the bum-towel, from the shape of its tail. The long-tailed tit was originally classified as a true tit of the Parus genus. Since then, it and its relatives have been reclassified as a distinct family, the Aegithalidae, containing three genera: • Aegithalos (long-tailed tits), nine living species including A. caudatus • Psaltria (pygmy bushtit), monotypic • Psaltriparus (American bushtit), monotypic. • Aegithalos caudatus caudatus × europaeus (Northern × Central European Long-tailed Tit) This species is the only representative of the family Aegithalidae found in northern Eurasia. The long-tailed tit exhibits complex global variation with 17 races recognised, divisible into three groups: • the A. c. caudatus group in northern Europe and Asia. A. c. caudatus has a pure white head • the A. c. europaeus group in southern and western Europe, north-east China, and Japan. Separating A. c. rosaceus from other members of the A. c. europaeus group though is problematic, relying on varying thickness of the crown stripes and amount of streaks and colour on the underparts Where the groups meet, there are extensive areas occupied by highly variable 'hybrids'. The British long-tailed tit, subspecies A. c. rosaceus, belongs to the A. c. europaeus group. ==Description==

This species has been described as a tiny (at only in length, including its tail), round-bodied tit with a short, stubby bill and a very long, narrow tail. The sexes look the same and young birds undergo a complete moult to adult plumage before the first winter. The plumage is mainly black and white, with variable amounts of grey and pink. Voice This species is often identified in the field through hearing its distinctive vocalisations. When they are in flocks, they issue constant contact calls, so they are often heard before they are seen. They have three main calls, a single high pitched pit, a 'triple trill' eez-eez-eez, and a rattling schnuur. These calls become faster and louder when the birds cross open ground or if an individual becomes separated from the group. ==Distribution and habitat==

The long-tailed tit is widespread throughout temperate Northern Europe and the Palearctic region, extending into the boreal Scandinavia and south into the Mediterranean zone. It inhabits deciduous and mixed woodlands with a well-developed shrub layer and favours edge habitats. It can also be found in scrubland, heathland with scattered trees, bushes and hedges, farmland, riverine woodland, and parks and gardens. The bird's year-round diet of insects and its social foraging behaviour influence its choice of habitat in winter, which is typically deciduous woodland with a canopy of oak, ash and locally sycamore species. For nesting, a strong preference is shown for scrub areas. The nest is often built in thorny bushes less than above the ground. ==Behaviour and ecology==

Food and feeding The long-tailed tit is insectivorous throughout the year. Its diet consists predominantly of arthropods, with a preference for the eggs and larvae of moths and butterflies. It occasionally takes vegetable matter such as seeds in autumn and winter. Nest The nest of the long-tailed tit is constructed from four materials: lichen, feathers, spider egg cocoons, spider silk, and moss, with over 6,000 pieces used for a typical nest. The nest is a flexible sac with a small, round entrance at the top, suspended either low in a gorse or bramble bush or high up in the forks of tree branches. The structural stability of the nest is provided by a mesh of moss and spider silk; the tiny leaves of the moss act as hooks and the spider's silken thread provides the loops, thus producing a natural form of velcro. The tit lines the outside with hundreds of flakes of pale lichens to provide camouflage. The inside of the nest is lined with more than 2,000 downy feathers to provide insulation. File:Long-tailed Tit nest building Dungeness, Kent 07 Mar 2009 A.jpg|A long-tailed tit in its nest File:Aegithalos caudatus MWNH 2283.JPG|Egg, Collection Museum Wiesbaden Aegithalos caudatus MHNT.ZOO.2010.11.180.1.jpg |Aegithalos caudatus – MHNT Social behaviour (1920), Territory in Bird Life, p. 145) , 2026 Outside of the breeding season, long-tailed tits form compact flocks of six to seventeen birds. These flocks are composed of family parties (parents and offspring) from the previous breeding season, along with any additional adults who helped raise a brood. These flocks will occupy and defend territories against neighbouring flocks. The driving force behind the flocking behaviour is thought to be that of winter roosting, being susceptible to cold; huddling increases survival through cold nights. When the breeding season begins, the flocks break up, and the birds attempt to breed in monogamous pairs. Males remain within the winter territory, while females have a tendency to wander to neighbouring territories. However, such inbreeding fitness costs are avoided by active kin discrimination during mate choice. recognition being established vocally. The helped nests have greater success due to higher provisioning rates and better nest defence. At the end of the breeding season, in June and July, the birds reform the winter flocks in their winter territory. Helpers There is a high nest failure rate due to high predation. If a nest fails after the beginning of May, the failed breeders will not attempt to re-nest, but they may become helpers at the nest of another pair, who are usually related. One study found that around 50% of nests had one or more helpers. By helping close relatives, helpers indirectly benefit in terms of fitness by increasing the survivability of related offspring. They may also gain greater access to mates and territories in the future. Helpers also gain experience in raising young, meaning that their future offspring have a better chance of survival. Both males and females are equally likely to become helpers. Parents may supplement their own efforts with the help of others, or, at the other extreme, reduce their own efforts in favour of the helpers' efforts. Although the survival rate for adults of both sexes is the same, juvenile males have a higher survival rate than juvenile females. Offspring raised with helpers have a higher survival rate than those raised without. Failed breeders who became helpers had a higher survival rate than those who did not. This may be due to the reduced energy expenditure involved in sharing a nest. This is similar phenomenon to that observed in acorn woodpeckers and green wood hoopoes. However, failed breeders that did not help are more likely to breed successfully in subsequent years, so there may be a cost of helping. This may be due to helpers having relatively poorer body conditions at the end of the breeding season, similar to pied kingfisher and white-winged chough. Successful breeders have a survivability rate around the survivability of failed breeders who became helpers. ==Status and conservation==

Globally, the species is common throughout its range, only becoming scarce at the edge of the distribution. Due to their small size they are vulnerable to extreme cold weather, with population losses of up to 80% being recorded in times of prolonged cold. It is thought that populations rapidly return to previous levels due to high breeding potential. ==Gallery==

File:Long-tailed tit (Aegithalos caudatus) juvenile 2.jpg|Red eye-ring of juvenile, Oxfordshire File:Long-tailed Tit (Aegithalos caudatus), Cumnor Hill, Oxford.jpg|Yellow eye-ring of young bird, Oxfordshire File:Long-tailed tit (Aegithalos caudatus) moulting.jpg|Young adult moulting in Oxfordshire File:Aegithalos_caudatus.jpg|Member of the white-headed subspecies File:'Aegithalos caudatus chick'.JPG|Juvenile on nest File:LongTailedTits 61.JPG|Brood of eight fledglings calling to be fed File:Lttits feeder.jpg|Long-tailed tits on an urban feeder, Plymouth, Devon File:20240421 Schwanzmeise (Aegithalos caudatus).jpg|Long-tailed tit in northern Germany File:Antipaired LTTs.jpg|Long-tailed tits resting, mid-afternoon in energy saving anti-parallel paired formation in a willow == Citations ==