Eurasian tree sparrow
|Eurasian tree sparrow|
|Adult of subspecies P. m. saturatus in Japan|
|Facial features of adult male of subspecies P. m. malaccensis in Malaysia.|
Breeding summer visitor
The Eurasian tree sparrow (Passer montanus) is a passerine bird in the sparrow family with a rich chestnut crown and nape, and a black patch on each pure white cheek. The sexes are similarly plumaged, and young birds are a duller version of the adult. This sparrow breeds over most of temperate Eurasia and Southeast Asia, where it is known as the tree sparrow, and it has been introduced elsewhere including the United States, where it is known as the Eurasian tree sparrow or German sparrow to differentiate it from the native unrelated American tree sparrow. Although several subspecies are recognised, the appearance of this bird varies little across its extensive range.
The Eurasian tree sparrow's untidy nest is built in a natural cavity, a hole in a building or the large nest of a European magpie or white stork. The typical clutch is five or six eggs which hatch in under two weeks. This sparrow feeds mainly on seeds, but invertebrates are also consumed, particularly during the breeding season. As with other small birds, infection by parasites and diseases, and predation by birds of prey take their toll, and the typical life span is about two years.
The Eurasian tree sparrow is widespread in the towns and cities of eastern Asia, but in Europe it is a bird of lightly wooded open countryside, with the house sparrow breeding in the more urban areas. The Eurasian tree sparrow's extensive range and large population ensure that it is not endangered globally, but there have been large declines in western European populations, in part due to changes in farming practices involving increased use of herbicides and loss of winter stubble fields. In eastern Asia and western Australia, this species is sometimes viewed as a pest, although it is also widely celebrated in oriental art.
The Eurasian tree sparrow is 12.5–14 cm (5–5 1⁄2 in) long, with a wingspan of about 21 cm (8.3 in) and a weight of 24 g (0.85 oz), making it roughly 10% smaller than the house sparrow. The adult's crown and nape are rich chestnut, and there is a kidney-shaped black ear patch on each pure white cheek; the chin, throat, and the area between the bill and throat are black. The upperparts are light brown, streaked with black, and the brown wings have two distinct narrow white bars. The legs are pale brown, and the bill is lead-blue in summer, becoming almost black in winter.
This sparrow is distinctive even within its genus in that it has no plumage differences between the sexes; the juvenile also resembles the adult, although the colours tend to be duller. Its contrasting face pattern makes this species easily identifiable in all plumages; the smaller size and brown, not grey, crown are additional differences from the male house sparrow. Adult and juvenile Eurasian tree sparrows undergo a slow complete moult in the autumn, and show an increase in body mass despite a reduction in stored fat. The change in mass is due to an increase in blood volume to support active feather growth, and a generally higher water content in the body.
The Eurasian tree sparrow has no true song, but its vocalisations include an excited series of tschip calls given by unpaired or courting males. Other monosyllabic chirps are used in social contacts, and the flight call is a harsh teck. A study comparing the vocalisations of the introduced Missouri population with those of birds from Germany showed that the US birds had fewer shared syllable types (memes) and more structure within the population than the European sparrows. This may have resulted from the small size of the founding North American population and a consequent loss of genetic diversity.
The Old World sparrow genus Passer is a group of small passerine birds that is believed to have originated in Africa, and which contains 15–25 species depending on the authority. Its members are typically found in open, lightly wooded, habitats, although several species, notably the house sparrow (P. domesticus) have adapted to human habitations. Most species in the genus are typically 10–20 cm (3.9–7.9 in) long, predominantly brown or greyish birds with short square tails and stubby conical beaks. They are primarily ground-feeding seed-eaters, although they also consume invertebrates, especially when breeding. Genetic studies show that the Eurasian tree sparrow diverged from the other Eurasian members of its genus relatively early, before the speciation of the house, plain-backed and Spanish sparrows. The Eurasian species is not closely related to the American tree sparrow (Spizelloides arborea), which is in a different family, the American sparrows.
The Eurasian tree sparrow's binomial name is derived from two Latin words: passer, "sparrow", and montanus, "of the mountains" (from mons "mountain"). The Eurasian tree sparrow was first described by Carl Linnaeus in his 1758 Systema Naturae as Fringilla montana, but, along with the house sparrow, it was soon moved from the finches (family Fringillidae) into the new genus Passer created by French zoologist Mathurin Jacques Brisson in 1760. The Eurasian tree sparrow's common name is given because of its preference of tree holes for nesting. This name, and the scientific name montanus, do not appropriately describe this species's habitat preferences: the German name Feldsperling ("field sparrow") comes closer to doing so.
This species varies little in appearance across its large range, and the differences between the seven extant subspecies recognised by Clement are slight. At least 15 other subspecies have been proposed, but are considered to be intermediates of the listed races.
- P. m. montanus, the nominate subspecies, ranges across Europe except southwestern Iberia, southern Greece, and the former Yugoslavia. It also breeds in Asia east to the Lena River and south to the northern regions of Turkey, the Caucasus, Kazakhstan, Mongolia and Korea.
- P. m. transcaucasicus, described by Sergei Aleksandrovich Buturlin in 1906, breeds from the southern Caucasus east to northern Iran. It is duller and greyer than the nominate race.
- P. m. dilutus, described by Charles Wallace Richmond in 1856, is resident in the extreme northeast of Iran, northern Pakistan and northwest India. It also occurs further north, from Uzbekistan and Tajikistan east to China. Compared to P. m. montanus, it is paler, with sandy-brown upperparts.
- P. m. tibetanus, the largest race by size, was described by Stuart Baker in 1925. It is found in the northern Himalayas, from Nepal east through Tibet to northwest China. It resembles P. m. dilutus, but is darker.
- P. m. saturatus, described by Leonhard Hess Stejneger in 1885, breeds in Sakhalin, the Kuril Islands, Japan, Taiwan and South Korea. It is deeper brown than the nominate subspecies and has a larger bill.
- P. m. malaccensis, described by Alphonse Dubois in 1885, is found from the southern Himalayas east to Hainan and Indonesia. It is a dark race, like P. m. saturatus, but is smaller and more heavily streaked on its upperparts.
- P. m. hepaticus, described by Sidney Dillon Ripley in 1948, breeds from northeast Assam to northwest Burma. It is similar to P. m. saturatus, but redder on its head and upperparts.
Distribution and habitat
The Eurasian tree sparrow's natural breeding range comprises most of temperate Europe and Asia south of about latitude 68°N (north of this the summers are too cold, with July average temperatures below 12 °C) and through Southeast Asia to Java and Bali. It formerly bred in the Faroes, Malta and Gozo. In South Asia it is found mainly in the temperate zone. It is sedentary over most of its extensive range, but northernmost breeding populations migrate south for the winter, and small numbers leave southern Europe for North Africa and the Middle East. The eastern subspecies P. m. dilutus reaches coastal Pakistan in winter and thousands of birds of this race move through eastern China in autumn.
The Eurasian tree sparrow has been introduced outside its native range, but has not always become established, possibly due to competition with the house sparrow. It was introduced successfully to Sardinia, eastern Indonesia, the Philippines and Micronesia, but introductions to New Zealand and Bermuda did not take root. Ship-carried birds colonised Borneo. This sparrow has occurred as a natural vagrant to Gibraltar, Tunisia, Algeria, Egypt, Israel, the United Arab Emirates, Morocco and Iceland. In North America, a population of about 15,000 birds has become established around St. Louis and neighbouring parts of Illinois and southeastern Iowa. These sparrows are descended from 12 birds imported from Germany and released in late April 1870 as part of a project to enhance the native North American avifauna. Within its limited US range of about 22,000 square kilometres (8,500 sq mi), the Eurasian tree sparrow has to compete with the house sparrow in urban centres, and is therefore mainly found in parks, farms and rural woods. The American population is sometimes referred to as the "German sparrow", to distinguish it from both the native American tree sparrow species and the much more widespread "English" house sparrow.
In Australia, the Eurasian tree sparrow is present in Melbourne, towns in central and northern Victoria and some centres in the Riverina region of New South Wales. It is a prohibited species in Western Australia, where it often arrives on ships from Southeast Asia.
Despite its scientific name, Passer montanus, this is not typically a mountain species, and reaches only 700 m (2,300 ft) in Switzerland, although it has bred at 1,700 m (5,600 ft) in the northern Caucasus and as high as 4,270 m (14,010 ft) in Nepal. In Europe, it is frequently found on coasts with cliffs, in empty buildings, in pollarded willows along slow water courses, or in open countryside with small isolated patches of woodland. The Eurasian tree sparrow shows a strong preference for nest-sites near wetland habitats, and avoids breeding on intensively managed mixed farmland.
When the Eurasian tree sparrow and the larger house sparrow occur in the same area, the house sparrow generally breeds in urban areas while the smaller Eurasian tree sparrow nests in the countryside. Where trees are in short supply, as in Mongolia, both species may utilise man-made structures as nest sites. The Eurasian tree sparrow is rural in Europe, but is an urban bird in eastern Asia; in southern and central Asia, both Passer species may be found around towns and villages. In parts of the Mediterranean, such as Italy, both the tree and the Italian or Spanish sparrows may be found in settlements. In Australia, the Eurasian tree sparrow is largely an urban bird, and it is the house sparrow which utilises more natural habitats.
Behaviour and ecology
The Eurasian tree sparrow reaches breeding maturity within a year from hatching, and typically builds its nest in a cavity in an old tree or rock face. Some nests are not in holes as such, but are built among roots of overhanging gorse or similar bush. Roof cavities in houses may be used, and in the tropics, the crown of a palm tree or the ceiling of a verandah can serve as a nest site. This species will breed in the disused domed nest of a European magpie, or an active or unused stick nest of a large bird such as the white stork, white-tailed eagle, osprey, black kite or grey heron. It will sometimes attempt to take over the nest of other birds that breed in holes or enclosed spaces, such as the barn swallow, house martin, sand martin or European bee-eater.
Pairs may breed in isolation or in loose colonies, and will readily use nest boxes. In a Spanish study, boxes made from a mixture of wood and concrete (woodcrete) had a much higher occupancy rate than wooden boxes (76.5% versus 33.5%), and birds nesting in woodcrete sites had earlier clutches, a shorter incubation period and more breeding attempts per season. Clutch size and chick condition did not differ between nest box types, but reproductive success was higher in woodcrete, perhaps because the synthetic nests were 1.5 °C warmer than their wooden counterparts.
The male calls from near the nest site in spring to proclaim ownership and attract a mate. He may also carry nest material into the nest hole. The display and nest building is repeated in autumn. The preferred locations for the autumn display are old Eurasian tree sparrow nests, particularly those where nestlings had hatched. Empty nest boxes, and sites used by house sparrows or other hole nesting birds, such as tits, pied flycatchers or common redstarts, are rarely used for the autumn display.
The untidy nest is composed of hay, grass, wool or other material and lined with feathers, which improve the thermal insulation. A complete nest consists of three layers; base, lining and dome. The typical clutch is five or six eggs (rarely more than four in Malaysia), white to pale grey and heavily marked with spots, small blotches, or speckling; they are 20 mm × 14 mm (0.79 in × 0.55 in) in size and weigh 2.1 g (0.074 oz), of which 7% is shell. The eggs are incubated by both parents for 12–13 days before the altricial, naked chicks hatch, and a further 15–18 days elapse before they fledge. Two or three broods may be raised each year; birds breeding in colonies produce more eggs and fledglings from their first broods than solitary pairs, but the reverse is true for second and third clutches. Females which copulate frequently tend to lay more eggs and have a shorter incubation time, so within-pair mating may be an indicator of the pairs' reproductive ability. There is a significant level of promiscuity; in a Hungarian study, more than 9% of chicks were sired by extra-pair males, and 20% of the broods contained at least one extra-pair young.
Hybridisation between the Eurasian tree sparrow and the house sparrow has been recorded in many parts of the world with male hybrids tending to resemble the Eurasian tree sparrow while females have more similarities with the house sparrow. A breeding population in the Eastern Ghats of India, said to be introduced, may also hybridise with house sparrows. On at least one occasion a mixed pair has resulted in fertile young. A wild hybridisation with the resident sparrows of Malta, which are intermediate between the Spanish sparrow (P. hispaniolensis) and Italian sparrows (P. italiae), was recorded in Malta in 1975.
The tree sparrow is a predominantly seed and grain eating bird which feeds on the ground in flocks, often with house sparrows, finches, or buntings. It eats weed seeds, such as chickweeds and goosefoot, spilled grain, and it may also visit feeding stations, especially for peanuts. It will also feed on invertebrates, especially during the breeding season when the young are fed mainly on animal food; it takes insects, woodlice, millipedes, centipedes, spiders and harvestmen.
Adults use a variety of wetlands when foraging for invertebrate prey to feed nestlings, and aquatic sites play a key role in providing adequate diversity and availability of suitable invertebrate prey to allow successful chick rearing throughout the long breeding season of this multi-brooded species. Large areas of formerly occupied farmland no longer provide these invertebrate resources due to the effects of intensive farming, and the availability of supplementary seed food within 1 kilometre (0.62 mi) of the nest-site does not influence nest-site choice, or affect the number of young raised.
In winter, seed resources are most likely to be a key limiting factor. At this time of year, individuals in a flock form linear dominance hierarchies, but there is no strong relation between the size of the throat patch and position in that hierarchy. This is in contrast to the house sparrow; in that species, fights to establish dominance are reduced by the display of the throat patch, the size of which acts as a signalling "badge" of fitness. Although there is evidence that the black throat patch of male, but not female, tree sparrows predicts fighting success in foraging flocks.
The risk of predation affects feeding strategies. A study showed increased distance between shelter and a food supply meant that birds visited a feeder in smaller flocks, spent less time on it and were more vigilant when far from shelter. Sparrows can feed as "producers", searching for food directly, or "scroungers", just joining other flock members who have already discovered food. Scrounging was 30% more likely at exposed feeding sites, although this is not due to increased anti-predator vigilance. A possible explanation is that riskier places are used by individuals with lower fat reserves.
Predators of the tree sparrow include a variety of accipiters, falcons and owls, such as the Eurasian sparrowhawk, common kestrel, little owl, and sometimes long-eared owl and white stork. It does not appear to be at an increased risk of predation during its autumn moult, despite having fewer flight feathers at that time. Nests may be raided by Eurasian magpies, jays, least weasels, rats, cats and constricting snakes such as the horseshoe whip snake.
Many species of birdlice are present on the birds and in their nests, and mites of the genus Knemidocoptes have been known to infest populations, resulting in lesions on the legs and toes. Parasitisation of nestlings by Protocalliphora blow-fly larvae is a significant factor in nestling mortality. Egg size does not influence nestling mortality, but chicks from large eggs grow faster.
Tree sparrows are also subject to bacterial and viral infections. Bacteria have been shown to be an important factor in the failure of eggs to hatch and in nestling mortality, and mass deaths due to Salmonella infection have been noted in Japan. Avian malaria parasites have been found in the blood of many populations, and birds in China were found to harbour a strain of H5N1 that was highly virulent to chickens.
The immune response of tree sparrows is less robust than that of the house sparrow and has been proposed as a factor in the greater invasive potential of the latter. The house sparrow and tree sparrow are the most frequent victims of roadkill on the roads of Central, Eastern and Southern Europe. The maximum recorded age is 13.1 years, but three years is a typical lifespan.
The tree sparrow has a large range estimated as 98.3 million square kilometres (38.0 million sq mi) and a population of 190–310 million individuals. Although the population is declining, the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (that is, declining more than 30% in ten years or three generations). For these reasons, the species' conservation status is evaluated at the global level as being of least concern.
Although the tree sparrow has been expanding its range in Fennoscandia and eastern Europe, populations have been declining in much of western Europe, a trend reflected in other farmland birds such as the skylark, corn bunting and northern lapwing. From 1980 to 2003, common farmland bird numbers fell by 28%. The collapse in populations seems to have been particularly severe in Great Britain, where there was a 95% decline between 1970 and 1998, and Ireland, which had only 1,000–1,500 pairs in the late 1990s. In the British Isles, such declines may be due to natural fluctuations, to which tree sparrows are known to be prone. Breeding performance has improved substantially as population sizes have decreased, suggesting that decreases in productivity were not responsible for the decline and that survival was the critical factor. The large decline in tree sparrow numbers is probably the result of agricultural intensification and specialisation, particularly the increased use of herbicides and a trend towards autumn-sown crops (at the expense of spring-sown crops that produce stubble fields in winter). The change from mixed to specialised farming and the increased use of insecticides has reduced the amount of insect food available for nestlings.
Relationships with humans
The tree sparrow is seen as a pest in some areas. In Australia, it damages many cereal and fruit crops and spoils cereal crops, animal feed and stored grain with its droppings. Quarantine rules prohibit the transport of this species into Western Australia.
Chairman Mao Zedong of China attempted in April 1958 to reduce crop damage by tree sparrows, estimated at 4.5 kg (9.9 lb) of grain per bird each year, by mobilising three million people and many scarecrows to drive the birds to death by exhaustion. Although initially successful, the "great sparrow campaign" had overlooked the numbers of locusts and other insect pests consumed by the birds, and crop yields fell, exacerbating a famine which led to the deaths of 30 million people between 1959 and 1961. The tree sparrow's consumption of insects has led to its use in agriculture to control fruit tree pests and the common asparagus beetle, Crioceris aspergi.
The tree sparrow has long been depicted in Chinese and Japanese art, often on a plant spray or in a flying flock, and representations by oriental artists including Hiroshige have featured on the postage stamps of Antigua and Barbuda, Central African Republic, China and the Gambia. More straightforward illustrations were used on the stamps of Belarus, Belgium, Cambodia, Estonia and Taiwan. The fluttering of the bird gave rise to a traditional Japanese dance, the Suzume Odori, developed in Sendai, which was depicted by artists such as Hokusai.
In the Philippines, where it is one of several species referred to as maya, and is sometimes specifically referred to as the "mayang simbahan" ("church maya" or "church sparrow"), the tree sparrow is the most common bird in the cities. Many urban Filipinos confuse it with the former national bird of the Philippines, the black-headed munia – also called a maya, but specifically differentiated in folk taxa as the "mayang pula" ("red maya").
- BirdLife International (2017). "Passer montanus". IUCN Red List of Threatened Species. IUCN. 2017: e.T22718270A119216586. doi:10.2305/IUCN.UK.2017-3.RLTS.T22718270A119216586.en. Retrieved 4 November 2018.
- Mullarney et al. 1999, p. 342
- "Tree Sparrow Passer montanus Linnaeus, 1758". Bird facts. British Trust for Ornithology. Retrieved 30 January 2009.
- Snow & Perrins 1998, pp. 1513–1515
- Clement, Harris & Davis 1993, pp. 463–465
- Mullarney et al. 1999, p. 343
- Lind, Johan; Gustin, Marco; Sorace, Alberto (2004). "Compensatory bodily changes during moult in Tree Sparrows Passer montanus in Italy" (PDF). Ornis Fennica. 81: 1–9. Archived from the original (PDF) on 2015-11-07.
- Lang, A. L.; Barlow, J. C. (1997). "Cultural evolution in the Eurasian Tree Sparrow: Divergence between introduced and ancestral populations" (PDF). The Condor. 99 (2): 413–423. doi:10.2307/1369948. JSTOR 1369948.
- Although Linnaeus gives the location as simply in Europa, the type specimen was from Bagnacavallo, Italy (Clancy, Philip Alexander (1948). "Remarks on Passer montanus (Linnaeus) in the Western Palaearctic Region with special reference to Passer catellatus Kleinschmidt, 1935: England". Bulletin of the British Ornithologists' Club. 68: 135.) Linnaeus's text for the tree sparrow translates "F[inch]. With dusky wings and tail, black and grey body paired white wing bars."
- Anderson 2006, p. 5
- Clement, Harris & Davis 1993, pp. 442–467
- Allende, Luis M.; Rubio, Isabel; Ruíz-del-Valle, Valentin; Guillén, Jesus; Martínez-Laso, Jorge; Lowy, Ernesto; Varela, Pilar; Zamora, Jorge; Arnaiz-Villena, Antonio (2001). "The Old World sparrows (genus Passer) phylogeography and their relative abundance of nuclear mtDNA pseudogenes" (PDF). Journal of Molecular Evolution. 53 (2): 144–154. CiteSeerX 10.1.1.520.4878. doi:10.1007/s002390010202. PMID 11479685. Archived from the original (PDF) on 21 July 2011.
- Arnaiz-Villena, A.; Gómez-Prieto, P.; Ruiz-de-Valle, V. (2009). "Phylogeography of finches and sparrows". Animal Genetics. Nova Science Publishers. ISBN 978-1-60741-844-3. Archived from the original on 2012-09-02. Retrieved 2014-12-08.
- Byers, Curson & Olsson 1995, pp. 267–268
- Linnaeus 1758, p. 183 F. remigibus rectricibusque fuscis, corpore griseo nigroque, alarum fascia alba gemina
- Brisson 1760, p. 36
- Summers-Smith 1988, p. 217
- Vaurie, Charles; Koelz, W. (1949). "Notes on some Ploceidae from western Asia". American Museum Novitates. 1406: 22–26. hdl:2246/2345.
- Krishna Raju, K. S. R.; Price, Trevor D. (1973). "Tree Sparrow Passer montanus (L.) in the Eastern Ghats". Journal of the Bombay Natural History Society. 70 (3): 557–558.
- Rasmussen & Anderton 2005
- Arlott 2007, p. 222
- Cocker & Mabey 2005, pp. 442–443
- del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi; Christie, David A.; de Juana, Eduardo, eds. (2013). "Eurasian Tree Sparrow (Passer montanus)". Handbook of the Birds of the World Alive. Barcelona: Lynx Edicions. Retrieved 25 October 2018.
- Barlow, Jon C.; Leckie, Sheridan N. Pool, A. (ed.). "Eurasian Tree Sparrow (Passer montanus)". The Birds of North America Online. Ithaca: Cornell Laboratory of Ornithology. Retrieved 30 January 2009.
- Forbush 1907, p. 306
- Massam, Marion. "Sparrows" (PDF). Farmnote No. 117/99. Agriculture Western Australia. Archived from the original (PDF) on 12 August 2008. Retrieved 1 February 2009.
- Field, Rob H.; Anderson, Guy (2004). "Habitat use by breeding Tree Sparrows Passer montanus". Ibis. 146 (2): 60–68. doi:10.1111/j.1474-919X.2004.00356.x.
- Melville, David S.; Carey, Geoff J. (1998). "Syntopy of Eurasian Tree Sparrow Passer montanus and House Sparrow P. domesticus in Inner Mongolia, China" (PDF). Forktail. 13: 125. Archived from the original (PDF) on 2011-06-10.
- Summers-Smith 1988, p. 220
- "An Age entry for Passer montanus". AnAge, the animal ageing and longevity database. Retrieved 30 January 2009.
- Coward 1930, pp. 56–58
- Robinson & Chasen 1927–1939, Chapter 55 (PDF) 284–285
- Bochenski, Marcin (2005). Pinowski, Jan (ed.). "Nesting of the sparrows Passer spp. in the White Stork Ciconia ciconia nests in a stork colony in Klopot (W Poland)" (PDF). International Studies on Sparrows. 30: 39–41. Archived from the original (PDF) on 24 September 2011.
- Czechowski, Pawel (2007). Pinowski, Jan (ed.). "Nesting of Tree Sparrow Passer montanus in the nest of Barn Swallow Hirundo rustica" (PDF). International Studies on Sparrows. 32: 35–37. Archived from the original (PDF) on 24 September 2011.
- Hegyi, Z.; Sasvári, L. (1994). "Alternative reproductive tactics as viable strategies in the Tree Sparrow (Passer montanus)" (PDF). Ornis Hungaria. 4: 9–18.
- García-Navas, Vicente; Arroyo, Luis; Sanz, Juan José; Díaz, Mario (2008). "Effect of nestbox type on occupancy and breeding biology of tree sparrows Passer montanus in central Spain". Ibis. 150 (2): 356–364. doi:10.1111/j.1474-919X.2008.00799.x. hdl:10261/110551. Archived from the original (PDF) on 30 September 2010.
- Pinowski, Jan; Pinowska, Barbara; Barkowska, Miloslawa; Jerzak, Leszek; Zduniak, Piotr; Tryjanowski, Piotr (June 2006). "Significance of the breeding season for autumnal nest-site selection by Tree Sparrows Passer montanus". Acta Ornithologica. 41 (1): 83–87. doi:10.3161/068.041.0103.
- Pinowski, Jan; Haman, Andrzej; Jerzak, Leszek; Pinowska, Barbara; Barkowska, Miloslawa; Grodzki, Andrzej; Haman, Krzysztof (2006). "The thermal properties of some nests of the Eurasian Tree Sparrow Passer montanus" (PDF). Journal of Thermal Biology. 31 (7): 573–581. doi:10.1016/j.jtherbio.2006.05.007. Archived from the original (PDF) on 31 October 2011.
- "Eurasian Tree Sparrow Passer montanus". Bird guide. Cornell Laboratory of Ornithology. Retrieved 30 January 2009.
- Sasvari, L.; Hegyi, Z. (1994). "Colonial and solitary nesting choice as alternative breeding tactics in tree sparrow Passer montanus". Journal of Animal Ecology. 63 (2): 265–274. doi:10.2307/5545. JSTOR 5545.
- Heeb, P. (June 2001). "Pair copulation frequency correlates with female reproductive performance in Tree Sparrows Passer montanus". Journal of Avian Biology. 32 (2): 120–126. doi:10.1034/j.1600-048X.2001.320204.x.
- Seress, G.; Szabó, K.; Nagy, D.; Liker, A.; Pénzes, Z. (2007). "Extra-pair paternity of tree sparrow (Passer montanus) in a semi-urban population" (PDF). TISCIA. 36: 17–21. Archived from the original (PDF) on 9 December 2008.
- Cordero, P. (1991). "Phenotypes of adult hybrids between House Sparrows Passer domesticus and Tree Sparrow Passer montanus". Bulletin of the British Ornithologists' Club. 111: 44–46.
- Raju, K. S. R. Krishna; Price, Trevor D. (1973). "Tree Sparrow Passer montanus (L.) in the Eastern Ghats". J. Bombay Nat. Hist. Soc. 70 (3): 557–558.
- Solberg, Erling Johan; Ringsby, Thor Harald; Altwegg, Andreas; Sæther, Bernt-Erik (January 2000). "Fertile House Sparrow X Tree Sparrow (Passer domesticus × Passer montanus) hybrids?" (PDF). Journal of Ornithology. 141 (1): 10–104. doi:10.1007/BF01651777. Archived from the original (PDF) on 2011-07-21.
- Solberg, E. J.; Jensen, H.; Ringsby, T. H.; Sæther, B.-E. (2006). "Fitness consequences of hybridization between house sparrows (Passer domesticus) and tree sparrows (P. montanus)" (PDF). Journal of Ornithology. 147 (3): 504–506. doi:10.1007/s10336-005-0033-5. Archived from the original (PDF) on 2011-07-21.
- Solberg, E. J.; Ringsby, T. H. (1996). "Hybridisation between house sparrow Passer domesticus and tree sparrow Passer montanus" (PDF). Journal für Ornithologie. 137 (4): 525–528. doi:10.1007/BF01661107. Archived from the original (PDF) on 2011-07-21.
- "Tree sparrow – Passer montanus – Family: Fringillidae/Passeridae". Natural England. Archived from the original on 20 July 2011. Retrieved 31 January 2009.
- Torda, G.; Liker, András; Barta, Z. (2004). "Dominance hierarchy and status signalling in captive tree sparrow (Passer montanus) flocks" (PDF). Acta Zoologica Academiae Scientiarum Hungaricae. 50 (1): 35–44.
- Mónus, Ferenc; Liker, A; Pénzes, Zoltán; Barta, Zoltán (2017). "Status signalling in male but not in female Eurasian Tree Sparrows Passer montanus" (PDF). Ibis. 159: 180–192. doi:10.1111/ibi.12425.
- Barta, Zoltán; Liker, András; Mónus, Ferenc (February 2004). "The effects of predation risk on the use of social foraging tactics". Animal Behaviour. 67 (2): 301–308. doi:10.1016/j.anbehav.2003.06.012.
- Costantini, David; Casagrande, Stefania; Di Lieto, Giuseppe; Fanfani, Alberto; Dell'Omo, Giacomo (2005). "Consistent differences in feeding habits between neighbouring breeding kestrels" (PDF). Behaviour. 142 (9): 1409–1421. doi:10.1163/156853905774539409. Archived from the original (PDF) on 10 July 2007.
- Shao, M.; Hounsome, T.; Liu, N. (2007). "The summer diet of the Little Owl (Athene noctua) in the desert of north-west China". Journal of Arid Environments. 68 (4): 683–687. doi:10.1016/j.jaridenv.2006.08.010.
- Obuch, Ján; Kristin, Anton (2004). "Prey composition of the little owl Athene noctua in an arid zone (Egypt, Syria, Iran)" (PDF). Folia Zoologica. 53 (1): 65–79. Archived from the original (PDF) on 2011-07-18. Retrieved 2009-01-31.
- Berthold, Peter (2004). "Aerial "flycatching": non-predatory birds can catch small birds in flight". Journal of Ornithology. 145 (3): 271–272. doi:10.1007/s10336-004-0041-x.
- Bertolino, Sandro; Ghiberti, Elena; Perrone, Aurelio (2001). "Feeding ecology of the long-eared owl (Asio otus) in northern Italy: is it a dietary specialist?". Canadian Journal of Zoology. 79 (12): 2192–2198. doi:10.1139/z01-182.
- Lind, J. (2001). "Escape flight in moulting Eurasian Tree Sparrows (Passer montanus)" (PDF). Functional Ecology. 15: 29–35. doi:10.1046/j.1365-2435.2001.00497.x. Archived from the original (PDF) on 2016-03-03.
- Veiga, J. P. (1990). "A comparative study of reproductive adaptations in house and tree sparrows" (PDF). The Auk. 107 (1): 45–59. JSTOR 4087801.
- Cordero, P. J.; Salaet, M. "Breeding season, population and reproduction rate of the tree sparrow (Passer montanus, L.) in Barcelona, NE Spain." in Pinowski & Summers-Smith 1990, pp. 169–177
- Cordero, P. J. "Predation in House Sparrow and Tree Sparrow (Passer sp.) nests" in Pinowski, Kavanagh & Górski 1991, pp. 111–120
- Skoracki, Maciej (2002). "Three new species of the ectoparasitic mites of the genus Syringophiloidus Kethley, 1970 (Acari: Syringophilidae) from passeriform birds from Slovakia". Folia Parasitologica. 49 (4): 305–313. doi:10.14411/fp.2002.057. PMID 12641205.
- Boonkong, Suthasanee; Meckvichai, Wina (1987). "Arthropod parasites of the tree sparrow (Passer montanus Linnaeus, 1758) in Bangkok, Thailand" (PDF). Journal of the Scientific Society of Thailand. 13 (4): 231–237. doi:10.2306/scienceasia1513-1874.1987.13.231.
- Mainka, S. A.; Melville D. S.; Galsworthy A.; Black, S. R. (1994). "Knemidocoptes sp. on wild passerines at the Mai Po nature reserve, Hong Kong". Journal of Wildlife Diseases. 30 (2): 254–256. doi:10.7589/0090-3558-30.2.254. PMID 8028111.
- Puchala, Peter (2004). "Detrimental effects of larval blow flies (Protocalliphora azurea) on nestlings and breeding success of Tree Sparrows (Passer montanus)". Canadian Journal of Zoology. 82 (8): 1285–1290. doi:10.1139/z04-111.
- Pinowska, Barbara; Barkowska, Miloslawa; Pinowski, Jan; Bartha, Andrzej; Hahm, Kyu-Hwang; Lebedeva, Natalia (2004). "The effect of egg size on growth and survival of the Tree Sparrow Passer montanus nestlings". Acta Ornithologica. 39 (2): 121–135. doi:10.3161/068.039.0209.
- Pinowksi, J.; Barkowska, M.; Kruszewicz, A. H.; Kruszewicz, A. G. (1994). "The causes of the mortality of eggs and nestlings of Passer spp" (PDF). Journal of Biosciences. 19 (4): 441–451. doi:10.1007/BF02703180.
- Une, Yumi; Sanbe, Asuka; Suzuki, Satoru; Niwa, Takeshi; Kawakami, Kazuto; Kurosawa, Reiko; Izumiya, Hidemasa; Watanabe, Haruo; Kato, Yukio (2008). "Salmonella enterica Serotype Typhimurium Infection Causing Mortality in Eurasian Tree Sparrows (Passer montanus) in Hokkaido" (PDF). Japan Journal of Infectious Diseases. 61: 166–167. Archived from the original (PDF) on 29 September 2011.
- Shurulinkov, Peter; Golemansky, Vassil (2003). "Plasmodium and Leucocytozoon (Sporozoa: Haemosporida) of wild birds in Bulgaria" (PDF). Acta Protozoolica. 42: 205–214. Archived from the original (PDF) on 13 June 2004.
- Kou, Z.; Lei, F. M.; Yu, J.; Fan, Z. J.; Yin, Z. H.; Jia, C. X.; Xiong, K. J.; Sun, Y. H.; Zhang, X. W.; Wu, X. M.; Gao, X. B.; Li, T. X. (2005). "New genotype of Avian Influenza H5N1 Viruses isolated from Tree Sparrows in China" (PDF). Journal of Virology. 79 (24): 15460–15466. doi:10.1128/JVI.79.24.15460-15466.2005. PMC 1316012. PMID 16306617.
- Lee, Kelly A.; Martin, Lynn B., II; Wikelski, Martin C. (2005). "Responding to inflammatory challenges is less costly for a successful avian invader, the house sparrow (Passer domesticus), than its less-invasive congener" (PDF). Oecologia. 145 (2): 244–251. doi:10.1007/s00442-005-0113-5. PMID 15965757. Archived from the original (PDF) on 2006-09-21.CS1 maint: multiple names: authors list (link)
- Erritzoe, J.; Mazgajski, T. D.; Rejt, L. (2003). "Bird casualties on European roads — a review" (PDF). Acta Ornithologica. 38 (2): 77–93. doi:10.3161/068.038.0204.
- "Research highlights decline of farm and forest birds". BirdLife International. 8 June 2005. Retrieved 3 February 2009.
- BirdLife International (2004). "Passer montanus, Eurasian Tree Sparrow" (PDF). Birds in Europe: population estimates, trends and conservation status. Conservation Series No. 12. Cambridge, England: BirdLife International.
- "Tree sparrow". Conservation case studies. Royal Society for the Protection of Birds. Archived from the original on 15 January 2010. Retrieved 3 February 2009.
- "Tree sparrow on the increase on east coast". RTÉ News. 23 January 2012.
- "Tree Sparrow Passer montanus". Breeding Birds in the Wider Countryside. British Trust for Ornithology. Archived from the original on 27 February 2008. Retrieved 3 February 2009.
- McCarthy, Michael (2 August 2006). "The secret life of sparrows". The Independent. London. Retrieved 30 January 2009.
- Dix, M. E.; Johnson, R. J.; Harrell, M. O.; Case, R. M.; Wright R. J.; Hodges, L.; Brandle, J. R.; Schoeneberger, M. M.; Sunderman, N. J.; Fitzmaurice, R. L.; Young, L. J.; Hubbard, K. G. (March 1995). "Influences of trees on abundance of natural enemies of insect pests: a review". Agroforestry Systems. 29 (3): 303–311. doi:10.1007/BF00704876.
- "Stamps showing Eurasian Tree Sparrow Passer montanus". Birdtheme.org. Retrieved 18 February 2009.
- "Sketches by Hokusai (Hokusai Manga)". Nipponia No. 27. December 15, 2003. Retrieved 6 February 2009.
- Labro, Vicente (19 July 2007). "2 Philippine eagles spotted in Leyte forest". Philippine Daily Inquirer. Archived from the original on 10 May 2012. Retrieved 21 November 2008.
- Anderson, Ted R. (2006). Biology of the Ubiquitous House Sparrow: From Genes to Populations. Oxford University Press. ISBN 978-0-19-530411-4.
- Arlott, Norman (2007). Birds of the Palearctic: Passerines. London: Collins. ISBN 978-0-00-714705-2.
- Brisson, Mathurin Jacques (1760). Ornithologie ou méthode contenant la division des oiseaux en ordres, sections, genres, especes & leurs variétés. A laquelle on a joint une description exacte de chaque espece, avec les citations des auteurs qui en ont traité, les noms qu'ils leur ont donnés, ceux que leur ont donnés les différentes nations, & les noms vulgaires. Ouvrage enrichi de figures en taille-douce (in French). Paris: Bauche.
- Byers, Clive; Curson, Jon; Olsson, Urban (1995). Sparrows and Buntings: a Guide to the Sparrows and Buntings of North America and the World. Pica Press. ISBN 978-1-873403-19-8.
- Clement, Peter; Harris, Alan; Davis, John (1993). Finches and Sparrows: an Identification Guide. Christopher Helm. ISBN 978-0-7136-8017-1.
- Cocker, Mark; Mabey, Richard (2005). Birds Britannica. London: Chatto & Windus. ISBN 978-0-7011-6907-7.
- Coward, Thomas Alfred (1930). The Birds of the British Isles and Their Eggs. I (3rd ed.). Frederick Warne. ISBN 978-0-7232-0999-7.
- Forbush, Edward Howe (1907). Useful Birds and Their Protection. Boston: Massachusetts State Board of Agriculture.
- Kennedy, Robert S.; Gonzales, Pedro C.; Dickinson, Edward C.; Miranda, Hector; Fisher, Timothy H. (2000). A Guide to the Birds of the Philippines. Oxford University Press. ISBN 978-0-19-854668-9.
- Linnaeus, Carolus (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata (in Latin). Holmia: Laurentius Salvius.
- Mullarney, Killian; Svensson, Lars; Zetterstrom, Dan; Grant, Peter (1999). Collins Bird Guide. London: HarperCollins. ISBN 978-0-00-219728-1.
- Pinowski, Jan; Kavanagh, P. P.; Górski, W. (1991). Nestling mortality of granivorous birds due to microorganisms and toxic substances. Varsovia: Polish Scientific Publishers. ISBN 978-83-01-10476-4.
- Pinowski, Jan; Summers-Smith, J. Denis, eds. (1990). Granivorous birds in the agricultural landscape. Lomianki: Polish Academy of Sciences. ISBN 978-83-01-08460-8.
- Rasmussen, Pamela C.; Anderton, John C. (2005). Birds of South Asia: The Ripley Guide. Washington: Smithsonian Institution Press and Lynx Edicions. ISBN 978-84-87334-67-2.
- Robinson, Herbert C.; Chasen, Frederick Nutter (1927–1939). Birds of the Malay Peninsula. London: H. F. & G. Witherby. Archived from the original on 2009-02-01.
- Snow, David; Perrins, Christopher M. (editors) (1998). The Birds of the Western Palearctic. I–II (concise ed.). New York: Oxford University Press. ISBN 978-0-19-854099-1.CS1 maint: extra text: authors list (link)
- Summers-Smith, J. Denis (1988). The Sparrows. illustrated by Robert Gillmor. Calton, Staffs, England: T. & A. D. Poyser. ISBN 978-0-85661-048-6.
- Summers-Smith, J. Denis (January 1995). The Tree Sparrow. Illustrated by Gillmor, Robert. J. Denis Summers-Smith. ISBN 978-0952538301.
|Wikispecies has information related to Passer montanus|
|Wikimedia Commons has media related to Passer montanus.|
|Wikisource has the text of the 1911 Encyclopædia Britannica article Sparrow.|
- Photographs and video on ARKive
- Skull image
- Ageing and sexing (PDF) by Javier Blasco-Zumeta & Gerd-Michael Heinze
- Tree sparrow videos, photos & sounds on the Internet Bird Collection
- Feathers of the Eurasian tree sparrow
- Documenting Passer montanus' nest, eggs, hatchlings, nestlings and fledglings by Isidro A.T. Savillo