Wikipedia

Blue jay

(Reguidit frae Blue Jay)
Blue jay
Scientific classification
Kinrick: Animalia
Phylum: Chordata
Cless: Aves
Order: Passeriformes
Faimily: Corvidae
Genus: Cyanocitta
Species: C. cristata
Binomial name
Cyanocitta cristata
Global range
     Breedin range     Year-roond range     Winterin rangeSee an aa text for recent range expansion.


The Blue Jay (Cyanocitta cristata) is a passerine bird in the faimily Corvidae, native tae North Americae. It bides throu maist o eastren an central Unitit States an soothren Canadae, altho wastren populations mey be migratory. It breeds in baith deciduous an coniferous forests, an is common near an in settlements. It is maistly blue wi a white breist an unnerparts, an a blue crest. It haes a black, U-shapen collar aroond its neck an a black mairch ahint the crest. Size atween sexes ar alike, an plumage disnae chynge throu the year. Thar Blue Jay haes fower unco subspecies.

The blue jay maistly baits on nits an seeds siclik acorns, saft fruits, arthropods, an betimes smaa vertebrates. It teepically gleans fuid frae trees, shrubs, an the grund, tho it whiles hawks insects frae the air. It bigs an appen cup nest in beuchs o trees, that baith sexes skairs in biggin. Thair clatch can hae twa tae seiven eggs, that are blueish or licht broun wi broun spots. Progeny ar altricial, an bruidit bi the female for 8–12 days efter hatchin. Thay mey bide wi thair parents for ane or twa month.

The bird's name derives frae its noisy, gabbie naitur.[2] It is whiles cried a "jaybird".[3]

Descrievin

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The Blue Jay meisurs 22–30 cm (9–12 in) frae bill tae tail an wechts 70–100 g (2.5–3.5 oz), wi a wingspan o 34–43 cm (13–17 in).[4][5] Jays frae Connecticut averaged 92.4 g (3.26 oz) in mass, whiles jays frae soothren Floridae averaged 73.7 g (2.60 oz).[6][7] Thare is a pronoonced crest on the heid, a croun o feathers, that mey be raised or lawered accordin tae the bird's muid. Whan excitit or aggressive, the crest mey be fu raised. When feartit, the crest bristles ootwards, brushlik. Whan the bird is feedin amang ither jays or restin, the crest is flat tae the heid.[8]

Its plumage is lavender-blue tae mid-blue in the crest, back, wings, an tail, an its face is white. The unnerside is aff-white an the neck is collared wi black that extends tae the sides o the heid. The wing primaries an tail are strangly barred wi black, sky-blue an white. The bill, legs, an een are aw black. Males an females ar near identical, but the male is a little muckler.[5][9]

As wi maist ither blue-hued birds, the Blue Jay's colouration isnae derived frae pigments but is the result of licht interference due tae the internal structur o the feathers;[10] gif a blue feather is crushed, the blue disappears as the structur is destroyed.[4] This is referred tae as structural coloration.

Distribution an habitat

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The blue jay occurs frae soothren Canadae throu the eastren an central USA sooth tae Florida an northeastren Texas. The wastren edge o the range staps whaur the arid pine forest an scrub habitat o the close relatit Steller's jay (C. stelleri) begins. O recent, the range o the Blue Jay haes extendit northwastwards sae that it is nou a rare but regular seen winter veesitor alang the northren US an soothren Canadian Pacific Coast.[4] As the twa species' ranges nou owerlap, C. cristata mey whiles hybridize wi Steller's jay.[11]

The northrenmaist subspecies C. c. bromia is migratory, subject tae necessity. It mey withdraw several hundrit kilometres sooth in the northrenmaist pairts o its range. Thoosands o blue jays hae been observed tae migrate in flocks alang the Great Lochs an Atlantic coasts. It migrates durin the daytime, in loose flocks o 5 tae 250 birds. Muckle aboot thair migratory behaviour remains a mystery. Some ar present throuoot winter in aw pairts o thair range. Young jays mey be mair likely tae migrate nor adults, but mony adults migrate an aa. Some individual jays migrate sooth ane year, stay north the neist winter, an then migrate sooth again the neist year. Tae date, naebody haes concretely wirkit oot hou thay migrate whan thay dae. Likely, it is relatit tae wather condeetions an hou abundant the winter fuid soorces are, that can determine whather ither northren birds will flit sooth.[12]

The blue jay occupies a variety o habitats athin its muckle range, frae the pine wids o Florida tae the spruce-fir forests o northren Ontario. It is less abundant in denser forests, preferrin mixed widlands wi aiks an beeches.[8] It haes expertly adaptit tae human activity, occurrin in pairks an residential areas, an can adapt tae halesale deforestation wi relative ease gif human activity creates ither means for the jays tae get bi.[13]

Subspecies

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Fower subspecies are generally acceptit, tho the variation athin this species is rather subtle an essentially clinal. Nae firm boundaries can be drawn atween the inland subspecies. The ranges o the coastal races are better deleemitit.[9]

  • Cyanocitta cristata bromia – northren Blue Jay
Canadae an northren USA. The lairgest subspecies, wi fairly dull plumage. Blue is rather pale.
  • Cyanocitta cristata cristata – coastal Blue Jay
Coastal USA frae North Carolina tae Texas, except soothren Florida. Mid-sized an vivid blue.
  • Cyanocitta cristata cyanotephra – interior Blue Jay
Inland USA, intergradin wi C. c. bromia tae the north. Mid-sized, quite dark blue on mantle contrastin cleanly wi very white unnerside.
  • Cyanocitta cristata semplei – Florida blue Jay
Soothren Florida. The smawest subspecies, much lik C. c. bromia in colour.

Behaviour

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A Merlin chasin a Blue Jay

The blue jay is a noisy, bold an aggressive passerine. It is a moderately slow flier (roughly 32–40 km/h (20–25 mph)) whan unprovoked.[14] It flies wi body an tail haudit level, wi slaw wing beats. Due tae its slaw flyin speeds, this species maks easy prey for hawks an houlets whan flyin in appen areas. Virtually aw the raptorial birds sympatric in distribution wi the blue jay mey predate it, espeicial swift bird-huntin speicialists siclik the Accipiter hawks. Diverse predators mey predate jay eggs an young up tae thair fledgin stage, includin tree squirrels, snakes, cats, crows, raccoons, opossums, ither jays an possibly mony o the same birds o prey that atteck adults.[15]

The blue jay can be beneficial tae ither bird species, as it mey chase predatory birds, siclik hawks an houlets, an will scream gif it sees a predator athin its territory. It haes been kent tae soond an alarm cry whan hawks or ither dangers are near an aa, an smawer birds eften recognise this cry an hide thairsels awa accordinly. It mey occasionally impersonate the cries o raptors, especial thon o the Reid-tailed an Reid-shouldered Hawks, possibly tae test gif a hawk is in the vicinity, tho possibly tae scare aff ither birds that mey compete for fuid soorces an aa.[12] It mey be aggressive tae humans that come ower close tae its nest an aa, an gif an houlet roosts near the nest durin the daytime the blue jay mobs it till it taks a new roost. Houaniver, blue jays hae been kent tae attack or kill ither smawer birds an sleepin, foliage-roostin bat species sic as Lasiurus borealis an aa.[16] Jays ar verra territorial birds, an thay will chase ithers frae a feeder for an easier meal. Addeetionally, the blue jay mey raid ither birds' nests, stealin eggs, chicks, an nests. Houiver, this mey nae be as common as is teepically thocht, as anerly 1% o fuid matter in ane study wis compromised bi birds.[12] Despite this, ither passerines mey still mob jays that come athin thair breedin territories.

Blue jays, lik ither corvids, are heichly curious an ar considert intelligent birds. Young individuals playfully snatch brichtly coloured or reflective objects, siclik bottle caps or pieces o aluminium foil, an haul them aroond till thay lose interest.[16] Whiles nae confirmt tae hae engaged in tuil uise in the wild, blue jays in captivity hae been observed uisin strips o newspaper as tuils tae obtain fuid,[12][17] whiles captive fledglins hae been observed attemptin tae appen the duir tae thair cages.[18]

Diet

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Whole peanuts an ither shelled fuid items are carried off in the beak tae be dealt wi at leisure.
Blue Jay cracking nuts

Blue jays hae strange black bills that thay uise for crackin nuts an acorns, fir uisual whiles haudin them wi thair feet, an for eatin corn, grains an seeds. Its fuid is soucht baith on the grund an in trees an includes virtually aw kent types o plant an ainimal soorces, sic as acorns an beech mast, weed seeds, grain, fruits an ither berries, peanuts, breid, meat, smaa invertebrates o mony types, scraps in toun pairks, bird-table fuid an rarely eggs an nestlins.[12] Blue jays will whiles cache fuid, tho tae whit extent differs widely amang individuals.[19] Altho seemingly contentious in thair general behaviour, blue jays are frequently subservient tae ither medium-sized birds that veesit bird-feeders. In Florida, blue jays wis dominatit at feeders bi Eastren gray squirrels, Florida Scrub-Jays, Common Grackles an Reid-heidit Widpeckers, aw o that wis occasionally observed tae aggressively prevent the jays frae feedin.[12]

Reproduction

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Nest in the tap o a little pine.

The matin saison begins in mid-Mairch, peaks in mid-Aprile tae Mey, an extends intae Julie. Ony suitable tree or muckle bush mey be uised for nestin, tho an evergreen is preferred. The nest is preferentially biggit at a heicht in the trees o 3 tae 10 m (9.8 tae 32.8 ft). It is cup-shaped an componed o twigs, smaa ruits, bark strips, moss, ither plant material, cloth, paper, an feathers, wi occasional mud addit tae the cup.

Blue jays arnae owerly picky anent nestin locations. Gif nae better place is available – e.g. in a hivily deforestit area – thay will even uise places lik the muckle mailboxes teepical o the rural Unitit States.[13] Thay appropriate nests o ither mid-sized sangbirds as lang as thay ar placed in suitable spots an aa; American robin nests are fir uisual uised bi blue jays, for ensaumple.

 
Fledgling in mid-Juin
 
Fledgling bird

Blue jays typically form monogamous pair bonds for life. Baith sexes big the nest an rear the young, tho anely the female bruids them. The male feeds the female whiles she is bruidin the eggs. Thare are fir uisual atween 3 an 6 (averagin 4 or 5) eggs laid an incubatit ower 16–18 days. The young fir uisual fledge atween 17–21 days efter hatchin.[16]

Efter the juveniles fledge, the faimily travels an forages thegither till early faw, whan the young birds disperse tae jouk competeetion for fuid during the winter. Sexual maturity is reached efter ane year o age. Blue jays hae been recordit tae live for mair nor 26 years in captivity an ane wild jay wis fand tae hae been aroond 17 an a hauf year auld.[20] A mair common lifespan for wild birds that survive tae adultheid is aroond 7 years.[21] Ayont predation an the occasional collision wi man-made objects, a reglar cause o mortality in recent tenyeirs haes been the Wast Nile Virus, that corvids as a hale seem espeicial susceptible tae. Houaniver, despite several major local declines, oweraw Blue Jays hinna seemt tae hae been depletit bi the disease.[15]

Vocalisations

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Blue jays can mak a lairge variety o soonds, an individuals mey vary perceptibly in thair cryin style. Lik ither corvids, thay mey learn tae mimic human speech. Blue jays can copy the cries o local hawks an aa, sae well that it is whiles difficult tae tell whit it is.[22] Thair vyce is teepical o maist jays in bein varied, but the maist reglar recognised soond is the alairm cry, that is a lood, almaist gull-lik scream. Thare is a heich-pitched jayer-jayer cry that increases in speed as the bird becomes mair agitatit as weel. This parteecular cry can be easily confused wi the chickadee's sang acause o the slaw stairtin chick-ah-dee-ee. Blue jays will uise thair cries tae baund thegither tae mob potential predators sic as hawks an drive them awa frae the jays' nests.

Blue jays hae quiet, almist subliminal calls an aa, that thay uise amang themselves in proximity. Ane o the maist distinctive cries o this teep is eften referrt tae as the "rusty pump" awin tae its squeaky resemblance tae the soond o an auld haund-operatit watter pump. The blue jay (an ither corvids) ar distinct frae maist ither sangbirds for uisin thair cry as a sang.

Cultural depiction an interpretation

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In auld African-American folklore o the soothren Unitit States the blue jay wis haudit tae be a servant o the Deil, an "wis nae encoontered on a Friday as he wis fetchin sticks doun tae Hell; forby, he wis sae happy an chirpy on a Setturday as he wis relieved tae return frae Hell".[23]

The blue jay wis adoptit as the team seembol o the Toronto Blue Jays Major League Baseball team, as weel as some o thair minor-league affiliates. Thair mascot is Ace, a blue jay.

The blue jay is the offeecial bird o the province o Prince Edward Island in Canadae.

Mordecai, an anthropomorphic blue jay, is ane o the main chairacters o the cartuin series Regular Show.

The Blue Jay is featurt in Mark Twain's "A Tramp Abroad", Chapter 3 "Baker's Blue-Jay Yarn".

References

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  1. ↑ BirdLife International (2012). "Cyanocitta cristata". IUCN Reid Leet o Threatened Species. Version 2013.2. Internaitional Union for Conservation o Naitur. Retrieved 26 November 2013. Cite has empty unkent parameter: |last-author-amp= (help)CS1 maint: uises authors parameter (link) CS1 maint: ref=harv (link)
  2. ↑ Coues, Elliot (1890). Key to North American birds (5th ed.). Boston, MA: Estes and Lauriat. p. 326. OCLC 469020022.
  3. ↑ "jaybird – definition of jaybird by the Free Online Dictionary, Thesaurus and Encyclopedia". Retrieved 20 Apryle 2011.
  4. ↑ a b c Cornell Lab of Ornithology (1999): Bird Guide – Blue Jay. Retrieved 2007-MAY-29.
  5. ↑ a b Frysinger, J. (2001): Animal Diversity Web: Cyanocitta cristata. Retrieved 2007-JUN-18.
  6. ↑ Jewell, S. D. 1986. Weights and wing lengths in Connecticut Blue Jays. Connecticut Warbler, 6: 47-49.
  7. ↑ Fisk, E. J. 1979. Fall and winter birds near Homestead, Florida. Bird-Banding 50:224-303.
  8. ↑ a b Nero, Robert W. (1991): Bird Fact Sheet – Blue Jay Archived 2009-02-04 at the Wayback Machine. Retrieved 2007-MAY-29.
  9. ↑ a b Madge, Steve & Burn, Hilary (1994): Crows and jays: a guide to the crows, jays and magpies of the world. A&C Black, London. ISBN 978-0-7136-3999-5
  10. ↑ Carpenter, Anita (Februar 2003). "What Color is a Bluejay?". Wisconsin Natural Resources Magazine. Archived frae the original on 31 Julie 2018. Retrieved 6 Mairch 2014.
  11. ↑ Rhymer, Judith M. & Simberloff, Daniel (1996). "Extinction by hybridization and introgression". Annu. Rev. Ecol. Syst. 27: 83–109. doi:10.1146/annurev.ecolsys.27.1.83.CS1 maint: multiple names: authors leet (link)
  12. ↑ a b c d e f Blue Jay. birds.cornell.edu
  13. ↑ a b Henninger, W.F. (1906). "A preliminary list of the birds of Seneca County, Ohio" (PDF). Wilson Bulletin. 18 (2): 47–60. Archived frae the original (PDF) on 19 August 2018. Retrieved 6 Mairch 2014.
  14. ↑ Texas Parks & Wildlife. Retrieved July 1, 2008.
  15. ↑ a b ADW: Cyanocitta cristata: INFORMATION
  16. ↑ a b c Oiseaux.net (2008): Blue Jay. Version of 2008-FEB-13. Retrieved 2008-FEB-14.
  17. ↑ Jones, Thony B. & Kamil, Alan C. (1973). "Tool-Making and Tool-Using in the Northern Blue Jay". Science. 180 (4090): 1076–1078. doi:10.1126/science.180.4090.1076.CS1 maint: multiple names: authors leet (link)
  18. ↑ American Rivers Archived 2013-12-18 at the Wayback Machine. tumblr.com
  19. ↑ AllAboutBirds.org – Blue Jay The Cornell Lab of Ornithology
  20. ↑ "Longevity Records Of North American Birds". U. S. Geological Survey: Bird Banding Laboratory. Retrieved 24 December 2012.
  21. ↑ "How Long Do Blue Jays Live?". Birdfact (in Inglis). Archived frae the original on 23 Mairch 2023. Retrieved 23 Mairch 2023.
  22. ↑ George, Philip Brandt. (2003): In: Baughman, Mel M. (ed.): Reference Atlas to the Birds of North America. National Geographic Society, Washington, D.C., p. 279, ISBN 978-0-7922-3373-2
  23. ↑ Ingersoll, Ernest (1923). Birds in legend, fable and folklore. New York: Longmans, Green and co. pp. 166–167. Retrieved 8 August 2009.

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