Corvus monedula

Corvus monedula, Photo: Michael Lahanas

Name

Corvus monedula Linnaeus, 1758

Vernacular names
Internationalization
Ελληνικά: Κάργια (Ευρωπαϊκή), Κολιός
English: Jackdaw
日本語: ニシコクマルガラス
Svenska: Kaja

Reference

Systema Naturae ed.10 p.106

The Jackdaw (Corvus monedula), sometimes known as the Eurasian Jackdaw, European Jackdaw, Western Jackdaw, or formerly simply the daw, is a dark-plumaged passerine bird in the crow family. It is found across Europe, western Asia and North Africa, and four subspecies are recognised. At 34–39 cm in length, it is one of the smallest species in Corvus, the genus of crows and ravens. It is a black-plumaged bird with grey nape and distinctive white irises. It is an omnivorous and opportunistic feeder, and eats a wide variety of plant material and invertebrates, as well as food waste from urban areas. The Jackdaw has benefited from clearing of forested areas and is found in farmland and urban areas, as well as open wooded areas and coastal cliffs.

Taxonomy

The Jackdaw was one of the many species originally described by Linnaeus in his 18th century work, Systema Naturae, and it still bears its original name of Corvus monedula.[2] The species name monedula is Latin for jackdaw.[3]

The common name jackdaw first appears in the 16th century, and is a compound of the forename Jack used in animal names to signify a small form (e.g. jack snipe) and the native English word daw. Formerly jackdaws were simply called daws.[4] Claims that the metallic chyak call is the origin of the jack part of the common name[5] are not supported by the Oxford English Dictionary.[6] Daw, first attested in the 15th century, is conjectured by the Oxford English Dictionary to be derived from an unattested Old English *dawe, citing cognates in Old High German tāha, Middle High German tāhe, tāchele, and modern German Dahle, Dohle, and dialectal Tach, Dähi, Däche, Dacha. The original Old English word cēo (pronounced with initial ch) gave modern English chough, which now refers to corvids of the genus Pyrrhocorax; Chaucer sometimes used this word,[4] as did Shakespeare in Hamlet although there has been debate about which species he was referring to.[7]

English dialect names are numerous. Scottish and north England dialect has had ka or kae since the 14th century. The midlands form of this was co or coo. Caddow is potentially a compound of ka and dow, a variant of daw. Other dialect or obsolete names include caddesse, cawdaw, caddy, chauk, college-bird (from dialectal college "cathedral"), jackerdaw, jacko, ka-wattie, chimney-sweep bird, from their nesting propensities, and sea-crow, from their frequenting coasts. It was also frequently known quasi-nominally as Jack.[8][9][10][11]

An archaic collective noun for a group of jackdaws is a "clattering."[12] Another term used is "train,"[13] however, in practice, most people use the more generic term "flock."

Subspecies

There are four recognised subspecies.[11][14] All European subspecies intergrade where their populations meet.[15] C. m. monedula integrates into C. m. soemmerringii with the transition zone running from Finland south across the Baltic, east Poland to Romania and Croatia.[16]

* C. m. monedula (Linnaeus, 1758), the nominate subspecies, breeds in south-east Norway, southern Sweden and northern and eastern Denmark, with occasional wintering birds in England and France. It has a pale nape and side of the neck, dark throat, and a light grey partial collar of variable extent.
* C. m. spermologus (Vieillot, 1817) occurs in western and central Europe, and winters in the Canary Islands and Corsica. It is darker in colour and lacks the whitish border at the base of the grey collar.[15]
* C. m. soemmerringii (Fischer, 1811) is found in north-eastern Europe, and north and central Asia, from the former Soviet Union to Lake Baikal and north-west Mongolia and south to Turkey, Israel and the eastern Himalayas. It winters in Iran and northwestern India (Kashmir). It is distinguished by its paler nape and side of the neck creating a contrasting black crown, and lighter grey partial collar.
* C. m. cirtensis (Rothschild and Hartert, 1912) is found in Morocco and Algeria in North Africa. The plumage is duller and more uniform dark grey, with the paler nape less distinct.[15]

Description

Measuring 34–39 cm (14–15 in), the jackdaw is the second smallest species in the genus Corvus. Most of the plumage is a shiny black, with a purple or blue sheen on the crown, forehead and secondaries, and a green-blue sheen on the throat, primaries, and tail. The cheeks, nape and neck are light grey to greyish-silver, and the underparts a slate-grey. The bill and legs are black.[17] The iris of adults is greyish- or silvery white. The iris of juvenile jackdaws is light blue, then brownish, before whitening around a year of age.[17]

In flight, jackdaws are separable from other corvids by their smaller size, faster and deeper wingbeats and proportionately narrower and less fingered wings. They also have a shorter, thicker neck, a much shorter bill and frequently fly in tighter flocks. The underwing is uniformly grey, unlike choughs.

On the ground, jackdaws strut about briskly and have an upright posture.

Sexes and ages are alike.[11][18]

Voice

Jackdaws are voluble birds. The call, frequently given in flight, is a metallic and somewhat squeaky, "chyak-chyak" or "kak-kak". Perched birds often chatter together, and before settling for the night large roosting flocks make a cackling noise. Jackdaws also have a hoarse, drawn-out alarm-call.[11]

Distribution and habitat
In Stockholm, Sweden

Jackdaws are resident over a large area stretching from north-west Africa through virtually all of Europe, including the British Isles and southern Scandinavia, westwards through central Asia to the eastern Himalayas and Lake Baikal. They are resident throughout Turkey, the Caucasus, Iran, Iraq, Afghanistan, Pakistan and north-west India.[15] The species has a large range, with an estimated global extent of between 1,000,000 and 10,000,000 km². It has a large global population, with an estimated 10 to 29 million individuals in Europe.[19]

Jackdaws are mostly resident, but the northern and eastern populations are more migratory.[16] Their range expands northwards into Russia to Siberia during summer, and retracts in winter.[11] They are winter vagrants to Lebanon, first recorded there in 1962.[20] In Syria they are winter vagrants and rare residents with some confirmed breeding.[21] The soemmerringii race occurs in south-central Siberia and extreme northwest China and is accidental to Hokkaido, Japan.[22]

A small number of Jackdaws reached the northwest of North America in the 1980s, presumedly ship-assisted, and have been found from Atlantic Canada to Pennsylvania.[23] They have also occurred as vagrants in Canada, the Faroe Islands, Gibraltar, Iceland, Mauritania and Saint Pierre and Miquelon. Jackdaws are regionally extinct in Malta and Tunisia.[24] The Jackdaw is reported to have once occurred in Egypt.[15]

They inhabit wooded steppes, pasture and cultivated land, coastal cliffs and villages and towns. They thrive as forested areas are cleared and converted to fields and open areas.[15]

Behaviour

Jackdaws are highly gregarious and are generally seen in small to large flocks, though males and females pair-bond for life and pairs stay together within flocks. Flock sizes increase in autumn and large flocks group together at dusk for communal roosting.[11] They become sexually mature in the first breeding season, and there is little evidence for divorce or extra pair coupling, even after multiple instances of reproductive failure.[25]

Jackdaws frequently congregate with Hooded Crows (Corvus cornix),[18] and during migration often accompany Rooks (C. frugilegus).

Like magpies, jackdaws are known to steal shiny objects such as jewellery to hoard in nests. John Gay in his Beggar's Opera notes that "A covetous fellow, like a jackdaw, steals what he was never made to enjoy, for the sake of hiding it"[26] and in Tobias Smollett's The Expedition of Humphry Clinker a scathing character assassination by Mr. Bramble runs "He is ungracious as a hog, greedy as a vulture, and thievish as a jackdaw."[27] Al Stewart's song, "Midas Shadow," contains the line, "Conquistador in search of gold for all the jackdaw reasons."

Feeding

The jackdaw forages in open areas and on the ground, but does take some food in trees.[15] Rubbish tips, bins, urban streets and gardens are also visited, more often early in the morning when there are fewer people about.[15] Jackdaws employ various feeding methods, such as jumping, pecking, clod-turning and scattering, probing the soil, and rarely digging. Flies around cow pats are caught by jumping from the ground or at times by dropping vertically from a few metres above onto the cow pat. Earthworms are not usually extracted from the ground by jackdaws but are eaten from freshly ploughed soil.[28]

In terms of animal food, jackdaws tend to feed upon small invertebrates found above ground between 2 and 18 mm in length, including larvae and pupae of Curculionidae, Coleoptera, Diptera and Lepidoptera. Snails, spiders and some insects also make up part of their animal diet. The jackdaw will also eat small rodents, eggs, and chicks. Jackdaws will feed on carrion, such as roadkill. The vegetable diet of jackdaws consists of farm grains (barley, wheat and oats), seeds of weeds, elderberries, acorns and various cultivated fruits.[28]

Jackdaws practice active food sharing, where the initiative for the transfer lies with the donor, with a number of individuals, regardless of sex and kinship. They also share more of a preferred food than a less preferred food.[29]

Breeding

Jackdaws usually nest in colonies with monogamous pairs collaborating to locate a nest site which they then defend from other pairs and predators most of the year.[25]

Jackdaws nest in cavities of trees, cliffs or ruined, and sometimes inhabited, buildings, often in chimneys, and even in dense conifers. They are famous for using church steeples for nesting, a fact reported in verse by 18th century English poet William Cowper

A great frequenter of the church,
Where, bishoplike, he finds a perch,
And dormitory too.[30]

Nests are usually constructed by a mated pair blocking up the crevice by dropping sticks into it; the nest is then built atop the platform formed.[31] This behaviour has led to blocked chimneys and even nests, with the jackdaw present, crashing down into fireplaces.[32] Nest platforms can attain great size—John Mason Neale notes that a "Clerk was allowed by the Churchwarden to have for his own use all that the caddows had brought into the Tower: and he took home, at one time, two cart-loads of good firewood, besides a great quantity of rubbish which he threw away."[33]

Gilbert White, in his popular book The Natural History of Selborne, notes that jackdaws used to nest in crevices beneath the lintels of Stonehenge, and describes a curious example of jackdaws using rabbit burrows for nest sites.[13]

Nests are lined with hair, rags, bark, soil, and many other materials. Jackdaws nest in colonies and often close to rooks.[5] Paler than those of other corvids,[34] the eggs are smooth, glossy pale blue speckled with dark brown, measuring approximately 36 x 26 mm. Clutches of normally 4-5 eggs, are incubated by the female for 17–18 days and fledge after 28–35 days, when they are fed by both parents.[5]

Jackdaws hatch asynchronously and incubation begins before clutch completion, which often leads to the death of the last-hatched young. The young which die in the nest do so quickly which minimises parental investment, and hence the brood size comes to fit the available food supply.[35] Infant jackdaws are altricial and thus are completely dependent on being fed by their parents until they fledge.[25]

Social behaviour

The jackdaw is a highly sociable species outside of the breeding season, occurring in flocks that can contain hundreds of birds.[31]

Konrad Lorenz studied the complex social interactions that occur in groups of jackdaws and published his detailed observations of their social behaviour in his book King Solomon's Ring. To study jackdaws, Lorenz put coloured rings on the legs of the jackdaws that lived around his house in Altenberg, Austria for identification, and he caged them in the winter because of their annual migration away from Austria. His book describes his observations on jackdaws' hierarchical group structure, in which the higher-ranking birds are dominant over lower ranked birds. The book also records his observations on jackdaws' strong male–female bonding; he noted that each bird of a pair both have the same rank in the hierarchy.

Every barnyard has a pecking order, as every farmer knows.[36][37] Jackdaws, like chickens, establish a hierarchy, and the position of the individual jackdaw determines all pecking rights. Who may peck whom? No jackdaw may peck another who ranks higher in the order. This is known in zoology as a "linear or straight-line hierarchy".[38] A high-ranking jackdaw may peck those of lower rank, and there is always that lowly jackdaw who is pecked by all, and can peck no one in return.

Jackdaws mate for life, and like most birds who follow this custom become engaged early in life, long before sexual maturity. First the young males of a new brood struggle among themselves to decide their individual status, and then pairing with females begins. The jackdaw female promptly upon pairing assumes the same social position of her male. His rights and restraints become her rights and restraints.

Should a female not secure a mate, then she remains the lowest ranked member of the flock in all social things. She is last to the food and last to the shelter. She is pecked by the lowliest, and snubbed by the least. Nor are there any lesser jackdaws on whom she can vent her frustration. As Lorenz related, it was one of these lowliest females that gave him much insight into jackdaw social behaviour. When a strong male returned to the flock, absent during the time of dominance struggles and male-female pairings, he quickly became the number one dominant male. He was forced to choose one of two unmated females for his mate. Instantly his new mate rocketed up the jackdaw social ladder and was able to peck others as much as she wanted, and she did. It took her a year to settle down. According to Lorenz the most significant factor of social behaviour was the immediate and intuitive grasp of the new hierarchy by each and every jackdaw. From the hour of her ascendancy, every jackdaw by oldest instinct knew his new place, and hers. She was "number one".[38]

Jackdaws have been observed sharing food and objects. The active giving of food is rare in primates, and in birds is found mainly in the context of parental care and courtship. Jackdaws show much higher levels of active giving than documented for chimpanzees. The function of this behaviour is not fully understood, although it has been found to be compatible with hypotheses of mutualism, reciprocity and harassment avoidance.[39]

Occasionally the flock makes "mercy killings" during which a sick or injured bird is mobbed until it is killed.[31]

Cultural depictions and folklore

Ancient Greek authors tell how a jackdaw, being a social creature, may be caught with a dish of oil which it falls into while looking at its own reflection.[40] The Roman poet Ovid also saw them as a harbinger of rain (Amores 2,6, 34).[41] In Greek legend, a princess Arne was bribed with gold by King Minos of Crete, and was punished for her avarice by being transformed into an equally avaricious jackdaw, who still seeks shiny things.[42] In Aesop's Fables, the jackdaw embodies stupidity in one tale, by starving while waiting for figs on a fig tree to ripen, and vanity in another - the daw sought to become king of the birds with borrowed feathers, but was shamed when they fell off.[41] Pliny notes how the Thessalians, Illyrians and Lemnians cherished jackdaws for destroying grasshoppers' eggs. The Veneti are fabled to have bribed the jackdaws to spare their crops.[40] Another ancient Greek and Roman adage runs, "The swans will sing when the jackdaws are silent," meaning that educated or wise people will speak after the foolish become quiet.[43]

In some cultures, a jackdaw on the roof is said to predict a new arrival; alternatively, a jackdaw settling on the roof of a house or flying down a chimney is an omen of death and coming across one is considered a bad omen.[44] The 12th century historian William of Malmesbury records the story of a woman who upon hearing a jackdaw chattering "more loudly than usual," grew pale and became fearful of suffering a "dreadful calamity", and that "while yet speaking, the messenger of her misfortunes arrived."[45]
Trzy Kawki coat of arms

The Ingoldsby Legends (1837) contains a poem named The Jackdaw of Rheims, which is about a jackdaw who steals a cardinal's ring and is made a saint.[46] A jackdaw standing on the vanes of a cathedral tower is meant to foretell rain. Czech superstition formerly held that if jackdaws are seen quarrelling, war will follow, and that jackdaws will not build nests at Sázava having been banished by Saint Procopius.[10]

In his 1979 work The Book of Laughter and Forgetting, Milan Kundera notes that Franz Kafka's father Hermann had a sign in front of his shop with a jackdaw painted next to his name, since kavka means jackdaw in Czech.

The Jackdaw features on the Ukrainian town of Halych's coat of arms, the town's name allegedly derived from the East Slavic word for the bird. Three Jackdaws are featured on the Trzy Kawki coat of arms, used by several szlachta (noble) families under the Polish-Lithuanian Commonwealth.[47] It is the symbolic bird of Southwest Finland.[48]

The sentence "Jackdaws love my big sphinx of quartz" is a commonly used example of a pangram, (i.e. a sentence that contains all 26 letters of the English alphabet), while the sentence itself is only 31 letters long.[49]

The University of Cambridge's online administrative database is officially called 'Jackdaw' and usage of its 'Email Address Look-Up' site is frequently referred to as a 'Jackdaw Search'.[50]

In the 1904 book "The Marvelous Land of Oz" by L. Frank Baum, Tip and his companions end up in a jackdaw's nest when they flew too far south of Oz.[51]

References

1. ^ BirdLife International (2004). Corvus monedula. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 12 May 2006.
2. ^ (Latin) Linnaeus, C (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.. Holmiae. (Laurentii Salvii).. pp. 105.
3. ^ Simpson, D.P. (1979). Cassell's Latin Dictionary (5 ed.). London: Cassell Ltd.. pp. 883. ISBN 0-304-52257-0.
4. ^ a b Goodwin, p. 78
5. ^ a b c "British Garden Birds: Jackdaw". http://www.garden-birds.co.uk/birds/jackdaw.htm.
6. ^ "Oxford English Dictionary: Jackdaw. 2nd ed. 1989". http://dictionary.oed.com/cgi/entry/50122724.
7. ^ Shakespeare, William, Edwards, Philip (2003). Hamlet, Prince of Denmark. Cambridge: Cambridge University Press. pp. 241. ISBN 0521532523.
8. ^ Swan, H. Kirke. A Dictionary of English and Folk-Names of British Birds, With their History, Meaning and first usage: and the Folk-lore, Weather-lore, Legends, etc., relating to the more familiar species. London: Witherby and Co. 1913.
9. ^ Wright, Joseph. The English Dialect Dictionary. Six volumes. London: Henry Frowde. 1898--1905.
10. ^ a b Swainson, Charles. Provincial Names and Folk Lore of British Birds. London: Trübner and Co., 1885.
11. ^ a b c d e f Mullarney, Killian; Svensson, Lars; Zetterstrom, Dan; Grant, Peter (1999). Collins Bird Guide. Collins. p. 335. ISBN 0002197286.
12. ^ First recorded in Lydgate's Debate between the Horse, Goose and Sheep, c.1430, as "A clatering of chowhis", and then in Juliana Berners Book of St. Albans, c.1480, as "a Clateryng of choughes."
13. ^ a b White, Gilbert (1833) The Natural Nistory of Selborne. London: N. Hailes, p. 163.
14. ^ "GlobalTwitcher.com: Eurasian Jackdaw Corvus monedula". http://www.globaltwitcher.com/artspec.asp?thingid=26248.
15. ^ a b c d e f g h Goodwin, p. 75
16. ^ a b "Identification and occurrence of "Eastern" Jackdaws in the Netherlands". http://www.xs4all.nl/~calidris/jackdaw.htm.
17. ^ a b Goodwin, p. 74
18. ^ a b R.F. Porter, et al., Birds of the Middle East. Princeton: Princeton University Press, 1996: 405.
19. ^ "Birdlife International. Data Zone. Species factsheet: Corvus monedula. Downloaded 23/11/2008". http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=5758.
20. ^ Ghassan Ramadan-Jaradi, Thierry Bara and Mona Ramadan-Jaradi. "Revised checklist of the birds of Lebanon." Sandgrouse. 2008. 30(1):22-69.
21. ^ D.A. Murdoch and K.F. Betton. "A checklist of the birds of Syria." Sandgrouse: Supplement 2. 2008: 12.
22. ^ Mark Brazil. The Birds of East Asia. 2008.
23. ^ John L. Dunn and Jonanthan Alderfer, National Geographic Field Guide to the Birds of North America. 5th ed. Washington, DC: National Geographic Society, 2006. p. 326
24. ^ "The IUCN Red List of Threatened Species: Corvus monedula. Downloaded 23/11/2008". http://www.iucnredlist.org/apps/redlist/details/146641/0/full.
25. ^ a b c Nathan J Emery, Amanda M Seed, Auguste M.P von Bayern, and Nicola S Clayton. "Cognitive adaptations of social bonding in birds." Philosophical Transactions of the Royal Society of London: B Biological Sciences. 2007 April 29; 362(1480): 489–505.
26. ^ John Gay. The Beggar's Opera. Edinburgh: A. Donaldson, 1760: 36.
27. ^ Tobias Smollett. Humphry Clinker. London: G. Routledge and Co., 1857: 78.
28. ^ a b J. D. Lockie "The Food and Feeding Behaviour of the Jackdaw, Rook and Carrion Crow." The Journal of Animal Ecology. 25:2 (Nov., 1956), pp. 421-428.
29. ^ Selvino R. de Kort, Nathan J. Emery and Nicola S. Clayton. "Food sharing in jackdaws, Corvus monedula: what, why and with whom?" Animal Behaviour 72:2 (August 2006): 297-304.
30. ^ The Poetical Works of William Cowper. Vol. 2. London: William Pickering, 1853. p. 336.
31. ^ a b c Wilmore, S. Bruce. Crows, jays, ravens and their relatives. London: David and Charles Ltd, 1977
32. ^ Greenoak, F. All the birds of the air; the names, lore and literature of British birds. London: Book Club Associates, 1979
33. ^ John Mason Neale (1846). "A Few Words to Parish Clerks and Sextons of Country Parishes.". London: Joseph Masters. http://anglicanhistory.org/neale/clerks.html.
34. ^ Goodwin, p. 47
35. ^ David Wingfield Gibbons. 'Hatching Asynchrony Reduces Parental Investment in the Jackdaw.' Journal of Animal Ecology (1987) 53: 403-414.
36. ^ Schjelderup-Ebbe, 1975 p. 36 cited in Rajecki, D. W. 1988
37. ^ Perrin, Porter G. (1955) Pecking Order 1927-54. American Speech 30(4):265-268
38. ^ a b Ardrey, Robert (1961). African Genesis. Bernadine Ardrey, illustrator. Atheneum, Dell. pp. 94–96. ISBN 0689100132. http://books.google.com/?id=9Yg1AAAAMAAJ&dq=%22Robert+Ardrey%22+%22African+Genesis%22. Retrieved June 1, 2009.
39. ^ Frequent food- and object-sharing during jackdaw (Corvus monedula) socialisation, Ethological Conference, Budapest, Hungary, 2005
40. ^ a b D'Arcy Wentworth Thompson, A Glossary of Greek Birds. Oxford, 1895. p. 89.
41. ^ a b de Vries, Ad (1976). Dictionary of Symbols and Imagery. Amsterdam: North-Holland Publishing Company. p. 275. ISBN 0-7204-8021-3.
42. ^ Graves, R (1955). "Scylla and Nisus". Greek Myths. London: Penguin. p. 308. ISBN 0-14-001026-2.
43. ^ Collected Works of Erasmus: Adages: Ivi1 to Ix100. Translated by Roger A. Mynors. University of Toronto Press, 1989. p. 314.
44. ^ "Old superstitions: Jackdaw". http://www.oldsuperstitions.com/index.php?query=jackdaw&submit=Go.
45. ^ "JACKDAW." A Dictionary of Superstitions. Ed. Iona Opie and Moira Tatem. Oxford University Press, 1996. Oxford University Press. Fatih University. 19 December 2008 Oxford Reference Online (for subscribers)
46. ^ Thomas Ingoldsby, The Ingoldsby Legends, Or, Mirth and Marvels, London: Richard Bentley, 1865: p.118-122.
47. ^ Górecki, Piotr (1992). Economy, Society, and Lordship in Medieval Poland: 1100-1250. New York, NEW YORK: Holmes and Meier Publishers, Inc.. ISBN 0841913188. OCLC 25787903
48. ^ Regional Council Southwest Finland. "Regional emblems of Southwest Finland". The Regional Council Southwest Finland website. The Regional Council Southwest Finland PL. http://www.varsinais-suomi.fi/in_English/Regional_emblems. Retrieved 2009-05-16.
49. ^ Fun with words
50. ^ http://jackdaw.cam.ac.uk/
51. ^ "The Marvelous Land of Oz, Baum, L. Frank. 1904

Cited text

* Goodwin D. (1983). Crows of the World. Queensland University Press, St Lucia, Qld. ISBN 0-7022-1015-3.

List of Cyprus birds