Long-tailed Titmice (Aegithalidae)

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Long-tailed titmice

(Aegithalidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Aegithalidae


Thumbnail description
Small tits with relatively long tails and loose feathering that gives a fluffy appearance. They are generally dark above, either gray or brown and lighter, and often white below. Many species have a black mask, and some show hints of pink in their feathering

Size
3.5–6.3 in (8.9–16 cm); 0.14–0.32 oz (4–9 g)

Number of genera, species
3 genera, 7 species

Habitat
Woodland and forest

Conservation status
Near Threatened: 2 species

Distribution
Western Europe to the Himalayas and the Far East; western North America and Mexico

Evolution and systematics

The long-tailed tit family (Aegithalidae) consists of three genera and seven species. Sibley and Ahlquist (1990) place the family in the superfamily Sylvioidea: this includes true tits, penduline tits, treecreepers, wrens, nuthatches, and others.

Physical characteristics

Family members range from 6.3 in (16 cm) to a mere 3.5 in (8.9 cm) in the aptly named pygmy tit (Psaltria exilis). All have long tails, particularly the long-tailed tit (Aegithalos caudatus), whose tail can make up half its total body length. Adult males and females have a similar plumage. They are generally dark above (gray or brown and lighter) and often white below. Many species have black mask and some show hints of pink in their feathering. A loose arrangement of body feathers makes them appear fluffy and endears them to many observers.

Distribution

Of the seven species, five are found in the Himalayas or mountainous parts of western China. The most widespread species is the long-tailed tit, with a range through western Europe and Asia, as far eastward as China and Japan. The most restricted species is the pygmy tit, which is endemic to Java. The only New World representative of the group is the bushtit (Psaltriparus minimus), found in western North America and Mexico.

Habitat

Long-tailed tits are primarily birds of edges and shrub layers of woodland and forest. In the Himalayas and mountains of China, they are found between 4,000 and 8,860 ft (1,200 and 2,700 m), or, in the case of the white-throated tit (Aegithalos niveogularis), up to the tree line at 13,100 ft (4,000 m).

Behavior

Birds in the long-tailed tit family spend most of their time in single-species flocks. For individual long-tailed tits, these flocks may be composed largely of related birds. Observers often first notice their presence on hearing constant chattering, the contact calls described as tsee-tsee-tsee (long-tailed tits) or pit-pit-pit (bushtit). Following this, a procession of single birds may typically be seen flying from one bush to another. In the evening, birds roost communally, with small groups lining up together on a suitable branch. If it is cold, they huddle shoulder to shoulder, with the flock's most dominant birds toward the middle of the row where most heat is retained. Long-tailed tits also have been observed roosting in holes in the ground.

Feeding ecology and diet

Birds of the long-tailed tit family spend much of their time in feeding flocks, searching for invertebrates and occasionally fruit and seed. Like other near relatives, they are extremely dextrous birds, comfortable hanging acrobatically from the thinnest of branches, holding an item of food in one claw while picking at it with the fine stubby bill.

Reproductive biology

Breeding season is from January (bushtit) to July. The diminutive pygmy tit on Java has a further season, from August to November.

During breeding, larger feeding and roosting flocks break down as individual birds pair together. In early parts of the breeding season, birds often still roost together; during a cold spell, feeding flocks may reform. Once the nest has been constructed, its warmth and security provide adequate roosting space for the pair alone.

Nests are enclosed oval or more elongated structures woven from moss, lichen, spider silk, and plant material. Once complete, they are quite light in color, possibly an attempt by the builders to camouflage them against light background breaks in the woodland canopy. Toward the top, each nest

has an entrance hole and is furnished with a soft lining that can include more than 2,000 feathers. They are commonly located low in the woodland shrub layer, suspended among or in the forks of suitable branches.

Clutch size is 2–12 eggs. The birds incubate for 12–18 days. Once hatched, youngsters are cared for by the parents and, in some cases, other members of the flock, often individuals whose own breeding attempts have failed. The young fledge within three weeks of hatching and remain with the parents' flock over the first winter.

Conservation status

Birds in the long-tailed tit family are common over much of their range and are not threatened. However, harsh winters can decimate the population by up to 80%. Himalayan and Chinese mountain species are common to locally common across their range with two exceptions: the sooty tit (Aegithalos fuliginosus) and white-throated tit (Aegithalos niveogularis) are scarce and listed as Near Threatened. Javanese endemic pygmy tits are locally common, but the ever-present threat of deforestation is of concern for this forest species.

Significance to humans

Bushtits visit garden feeders; long-tailed tits are rarely seen at feeders but their appearance in garden trees and parks is always popular.

Species accounts

List of Species

Long-tailed tit
Black-throated tit
Bushtit

Long-tailed tit

Aegithalos caudatus

taxonomy

Aegithalos caudatus Linnaeus, 1758. Nineteen subspecies are recognized.

other common names

French: Mésange à longue queue; German: Schwanzmeise; Spanish: Satrecito de Cola Larga.

physical characteristics

5–6.3 in (13–16 cm). Small tit with extremely long tail, plumage variable across range but generally a mix of black, white, and pink.

distribution

The most widespread of the long-tailed tit family with a range from western Europe through Asia, and into China and Japan.

habitat

Woodland, deciduous, and mixed with plenty of scrub in which to forage and nest.

behavior

A gregarious and acrobatic species, often first picked up on call (tsee-tsee-tsee). Flock frequently observed flying in single file, one bird at a time, from bush to bush. Roost communally on branches, huddled together in cold weather.

feeding ecology and diet

Largely invertebrates, especially insects and spiders.

reproductive biology

Nests March to June. Oval ball-shaped nest of moss and lichen, lined with feathers, located low in bushes and shrubs. Clutch 8–12 eggs, incubation 12–18 days, fledging 14–18 days. Nonbreeding birds may assist parents with feeding of young.

conservation status

Not threatened. Common across range, suffers after harsh winters, and takes a few years to recover population.

significance to humans

None known.


Black-throated tit

Aegithalos concinnus

taxonomy

Aegithalos concinnus Gould, 1855. Six subspecies are recognized.

other common names

English: Red-headed tit; French: Mésange à tête rousse; German: Rostkappen-schwanzmeise; Spanish: Satrecito de Cabeza Roja.

physical characteristics

4 in (10 cm); 0.14–0.32 oz (4–9 g). Small and very attractive tit with a rufous crown, black mask, white moustache, and black bib. Gray upper and buff-to-white underparts.

distribution

Himalayas, upland Myanmar, and Indochina.

habitat

Broadleaf forest.

behavior

A gregarious species foraging in the shrub layers of forests, often in mixed species flocks. Roosts communally. Contact call psip, psip and si-si-si.

feeding ecology and diet

Feeds on insects, seed, and fruit.

reproductive biology

Nests February to May. Nest a typical ball of moss and lichen positioned low in a bush. Clutch 3–9, incubation 15–16 days.

conservation status

Not threatened.

significance to humans

None known.


Bushtit

Psaltriparus minimus

taxonomy

Psaltriparus minimus Townsend, 1837. Eleven subspecies recognized.

other common names

English: Common bushtit, black-eared bushtit; French: Mésange masquée; German: Buschmeise; Spanish: Satrecito Común.

physical characteristics

4–4.5 in (10–11.4 cm); 0.18–0.21 oz (5–6 g). Tiny birds with a variable plumage range. Generally gray above with paler gray underparts. Coastal birds have brown caps and black-eared forms have black masks extending back to ear coverts.

distribution

Western United States (extending a little northward into Canada) and Mexico.

habitat

Deciduous and mixed woodlands, parks, and gardens.

behavior

A gregarious and active species that forages in large flocks. Roosts communally, as with other bushtits.

feeding ecology and diet

Feeds on insects, spiders, seed, and fruit.

reproductive biology

Nests January to June. Nest cucumber-shaped construction of twigs, moss, and lichen hung from the end of a branch. Clutch 5–7, incubation 12 days, fledging 14–15 days. Occasionally parents will be helped by other birds, as in long-tailed tits.

conservation status

Not threatened. Common, and increasing in some parts of its range.

significance to humans

None known.


Resources

Books

Harrap, S. and D. Quinn. Chickadees, Tits, Nuthatches and Treecreepers. Princeton: Princeton University Press, 1996.

Periodicals

Hansell, M. H. "The demand for feathers as building material by woodland nesting birds." Bird Study 42 (1995): 240–245.

Hansell, M. H. "The function of lichen flakes and white spider cocoons on the outer surface of bird's nests." Journal of Natural History 30 (1996): 303–311.

Hatchwell, B. J., C. Anderson, D. J. Ross, M. K. Fowlie, and P. G. Blackwell. "Social organization of cooperatively breeding long-tailed tits: kinship and spatial dynamics." Journal of Animal Ecology 70 (2001).

Tony Whitehead, BSc

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