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
Long-tailed titBlack-throated tit
Bushtit
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).
[Article by: Tony Whitehead, BSc]
