Jackdaw
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| Corvus monedula (Linnaeus, 1758) |
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 Jackdaw range
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The Jackdaw (Corvus monedula) is one of the smallest species (34–39 cm in length) in the genus of crows and ravens.
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[edit] Description
Most of the plumage is black or greyish black except for the cheeks, nape and neck, which are light grey to greyish silver. The iris of adults is greyish white or silvery white, the only member of the genus outside of the Australasian region to have this feature. The iris of juvenile jackdaws is light blue. The bird is sociable, moving around in pairs (male and female) or in larger groups, though the pairs of birds stay together within the flocks.
[edit] Distribution and habitat
Jackdaws are found over a large area stretching from North West Africa through virtually all of Europe, Iran, north-west India and Siberia, where they inhabit wooded steppes, woodland, cultivated land, pasture, coastal cliffs and villages and towns.
[edit] Behaviour
[edit] Diet
The Jackdaw mostly takes food from the ground but does take some food in trees. It eats insects and other invertebrates, weed seeds and grain, scraps of human food in towns, stranded fish on the shore, and will more readily take food from bird tables than other Corvus species.
[edit] Nesting
Jackdaws usually nest in colonies in cavities of trees, cliffs or ruined buildings and sometimes even in dense conifers. Eggs, normally 4-5, are incubated for 17-18 days and fledge after 30-35 days.
[edit] Voice
The voice is a "tchak-tchak" or "kak-kak" call.
[edit] Social behaviour
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". In order 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, the higher-ranking birds being 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 about the same rank in the hierarchy, and that a low-ranked female Jackdaw rocketed up the Jackdaw social ladder when she became the mate of a high-ranking male.
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.[1]
[edit] Other jackdaws
Another species closely related to European Jackdaw is the Daurian Jackdaw (Corvus dauricus) of eastern Asia. The European and Daurian Jackdaw together form the subgenus Coloeus.
[edit] Trivia
- "Kavka", the Czech word for jackdaw, is the origin of Franz Kafka's surname
- 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 is an omen of death and coming across one is considered a bad omen [2].
- Aesop wrote four fables about Jackdaws: The Eagle and the Jackdaw, The Vain Jackdaw, The Escaped Jackdaw, and The Jackdaw and the Pigeon
- In some versions of Microsoft Windows, when a user opened the windows\fonts folder and clicked on a typeface, fontview.exe would open and display this string: "Jackdaws love my big sphinx of quartz. 1234567890" using said typeface.
[edit] Image links
[edit] Video links
- Jackdaw videos on the Internet Bird Collection
[edit] References
- BirdLife International (2004). Corvus monedula. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006. Database entry includes justification for why this species is of least concern
