|Groundscraper thrush (Psophocichla litsitsirupa)|
Some 20, see text
The thrushes are a family, Turdidae, of passerine birds with a worldwide distribution. The family was once much larger before biologists decided the subfamily Saxicolinae, which includes the chats and European robins, were Old World flycatchers. Thrushes are small to medium-sized ground living birds that feed on insects, other invertebrates and fruit. Some unrelated species around the world have been named after thrushes due to their similarity to birds in this family.
Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feeding on the ground. The smallest thrush may be the forest rock thrush, at 21 g (0.74 oz) and 14.5 cm (5.7 in). However, the shortwings, which have ambiguous alliances with both thrushes and Old World flycatchers, can be even smaller. The lesser shortwing averages 12 cm (4.7 in). The largest thrush is the blue whistling thrush, at 178 g (6.3 oz) and 33 cm (13 in). The great thrush is similar in length, but less heavily built. Most species are grey or brown in colour, often with speckled underparts.
They are insectivorous, but most species also eat worms, land snails, and fruit. Many species are permanently resident in warm climates, while others migrate to higher latitudes during summer, often over considerable distances.
Thrushes build cup-shaped nests, sometimes lining them with mud. They lay two to five speckled eggs, sometimes laying two or more clutches per year. Both parents help in raising the young. In almost all cases, the nest is placed on a branch; the only exceptions are the three species of bluebird, which nest in holes.
Turdidae species spread the seeds of plants, contributing to the dispersal of many species and the recovery of ecosystems.
Plants have limited seed dispersal mobility away from the parent plant and consequently rely upon a variety of dispersal vectors to transport their propagules, including both abiotic and biotic vectors. Seeds can be dispersed away from the parent plant individually or collectively, as well as dispersed in both space and time.
Many bats and birds rely heavily on fruits for their diet, including birds in the families Cotingidae, Columbidae, Trogonidae, Turdidae, and Ramphastidae. While eating fruit, these animals swallow seeds and then later regurgitate them or pass them in their faeces. Such ornithochory has been a major mechanism of seed dispersal across ocean barriers.
Other seeds may stick to the feet or feathers of birds, and in this way may travel long distances. Seeds of grasses, spores of algae, and the eggs of molluscs and other invertebrates commonly establish in remote areas after long journeys of this sort. The Turdidae have a great ecological importance because some populations migrate long distances and disperse the seeds of endangered plant species at new sites, helping to eliminate inbreeding and increasing the genetic diversity of local flora.
The family Turdidae was introduced (as Turdinia) by the French polymath Constantine Samuel Rafinesque in 1815. The taxonomic treatment of this large family has varied significantly in recent years. Traditionally, the Turdidae included the small Old World species, like the nightingale and European robin in the subfamily Saxicolinae, but most authorities now place this group in the Old World flycatcher family Muscicapidae.
The family formerly included more species. At the time of the publication of the third edition of Howard and Moore Complete Checklist of the Birds of the World in 2003, the genera Myophonus, Alethe, Brachypteryx and Monticola were included in Turdidae. Subsequent molecular phylogenetic studies have shown that the species in these four genera are more closely related to species in the family Muscicapidae. As a consequence, these four genera are now placed in Muscicapidae. In contrast, the genus Cochoa which had previously been placed in Muscicapidae was shown to belong in Turdidae.
- Genus Neocossyphus: ant thrushes (2 species)
- Genus Stizorhina: rufous thrushes (2 species)
- Genus Geokichla: (21 species)
- Genus Zoothera: Asian thrushes (some 15 species, one recently extinct)
- Genus Ixoreus: varied thrush – related to other New World genera
- Genus Ridgwayia: Aztec thrush – related to Hylocichla
- Genus Cataponera: Sulawesi thrush
- Genus Grandala: grandala
- Genus Sialia: bluebirds (three species)
- Genus Myadestes: solitaires (10–11 living species, two or three recently extinct, includes formerly recognized genus Phaeornis)
- Genus Cichlopsis: rufous-brown solitaire – related to Catharus
- Genus Catharus: typical American thrushes and nightingale-thrushes (12 species)
- Genus Hylocichla: wood thrush
- Genus Entomodestes: solitaires (2 species) – related to Catharus
- Genus Turdus: true thrushes (some 65 species, one recently extinct)
- Genus Cochoa: cochoas (four species)
- Genus Chlamydochaera: fruithunter
- Genus Psophocichla: groundscraper thrush
The following genera have now been placed within Turdus:
- Genus Platycichla: (two species) – part of a South American group within Turdus
- Genus Nesocichla: Tristan thrush or starchy – part of a South American group within Turdus
- Genus Cichlherminia: forest thrush – genus paraphyletic with Turdus
Now usually considered a distinct family distantly related to Picathartes:
- Genus Chaetops: rock-jumpers (two species)
In popular culture
In The Hobbit, it is a thrush that shows Bilbo the hidden door into the mountain of Erebor, allowing him access to the dwarves' treasure kept by the dragon Smaug, and subsequently, having overheard Bilbo's account of the flaw in the dragon's armour, tells Bard the Bowman how to kill Smaug.
- Thrushes by Peter Clement. Princeton University Press (2001), ISBN 978-0-691-08852-5.
- Perrins, C. (1991). Forshaw, Joseph, ed. Encyclopaedia of Animals: Birds. London: Merehurst Press. pp. 186–187. ISBN 1-85391-186-0.
- Rafinesque, Constantine Samuel (1815). Analyse de la nature ou, Tableau de l'univers et des corps organisés (in French). Palermo: Self-published. p. 67.
- Bock, Walter J. (1994). History and Nomenclature of Avian Family-Group Names. Bulletin of the American Museum of Natural History. Number 222. New York: American Museum of Natural History. pp. 151, 252.
- Dickinson, E.C., ed. (2003). The Howard and Moore Complete Checklist of the Birds of the World (3rd ed.). London: Christopher Helm. ISBN 978-0-7136-6536-9.
- Voelker, G.; Spellman, G.M. (February 2004). "Nuclear and mitochondrial DNA evidence of polyphyly in the avian superfamily Muscicapoidea". Molecular Phylogenetics and Evolution. 30: 386–394. doi:10.1016/S1055-7903(03)00191-X.
- Sangster, G.; Alström, P.; Forsmark, E.; Olsson, U. (October 2010). "Multi-locus phylogenetic analysis of Old World chats and flycatchers reveals extensive paraphyly at family, subfamily and genus level (Aves: Muscicapidae)". Molecular Phylogenetics and Evolution. 57 (1): 380–392. doi:10.1016/j.ympev.2010.07.008. PMID 20656044.
- Gill, Frank; Donsker, David, eds. (2016). "Chats, Old World flycatchers". World Bird List Version 6.2. International Ornithologists' Union. Retrieved 20 May 2016.
- Dickinson, E.C.; Christidis, L., eds. (2014). The Howard & Moore Complete Checklist of the Birds of the World. Volume 2, Passerines (4th ed.). Eastbourne, U.K.: Aves Press. ISBN 978-0-9568611-2-2.
|Wikiquote has quotations related to: Thrushes|
|Wikimedia Commons has media related to Turdidae.|
- Thrush videos on the Internet Bird Collection
- High-resolution photo gallery of around 100 species.