View source for Blue jay

{{Short description|Species of bird}}
{{Use mdy dates|date=October 2025}}
{{Use American English|date=November 2024}}
{{Pp-semi-indef|small=yes}}
{{Other uses}}
{{redirect|Jay bird}}{{Distinguish||text=the [[Toronto Blue Jays]]}}
{{Speciesbox
| fossil_range = [[Piacenzian]]–present
| image = Blue jay in PP (30960).jpg
| image_caption = In [[Prospect Park, Brooklyn]], New York
| image2 = Cyanocitta cristata - Blue Jay - XC109601.ogg
| status = LC
| status_system = IUCN3.1
| status_ref = <ref>{{cite iucn |author=BirdLife International |date=2016 |title=''Cyanocitta cristata'' |article-number=e.T22705611A94027257 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22705611A94027257.en |access-date=June 25, 2022}}</ref>
| genus = Cyanocitta
| species = cristata
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])
| range_map = Cyanocitta cristata map.svg
| range_map_caption = Approximate distribution map
{{leftlegend|#7162c8|Year-round}}
{{leftlegend|#5f9ed3|Nonbreeding}}
| subdivision_ranks = Subspecies
| subdivision = 4 sspp., see [[#Subspecies|text]]
| synonyms = ''Corvus cristatus'' {{small|Linnaeus,&nbsp;1758}}
}}

The '''blue jay''' ('''''Cyanocitta cristata''''') is a [[passerine]] [[bird]] in the [[family (biology)|family]] [[Corvidae]], native to eastern North America. It lives in most of the eastern and central United States; some eastern populations may be migratory. Resident populations are also in Newfoundland, Canada; breeding populations are found across southern Canada. It breeds in both [[deciduous]] and [[coniferous]] forests, and is common in residential areas. Its coloration is predominantly blue, with a white chest and underparts, and a blue crest; it has a black, U-shaped collar around its neck and a black border behind the crest. Males and females are similar in size and [[plumage]], which does not vary throughout the year. Four subspecies have been recognized.

The blue jay feeds mainly on [[seed]]s and nuts, such as [[acorn]]s, which it may hide to eat later;<ref>{{cite news|url=https://www.discovermagazine.com/health/the-blue-jays-are-coming-hide-yo-kids-hide-yo-nuts|title=The blue jays are coming! Hide yo kids, hide yo nuts!|work=Discover Magazine|date=May 7, 2014|access-date=October 20, 2025}}</ref> soft fruits; [[arthropod]]s; and occasionally small [[vertebrate]]s. It typically [[gleaning (birds)|gleans]] food from trees, shrubs, and the ground, and sometimes [[hawking (birds)|hawks]] insects from the air. Blue jays can be very aggressive to other birds; they sometimes raid nests and have even been found to have [[Decapitation|decapitated]] other birds.<ref>{{cite web|url=https://travisaudubon.org/murmurations/bird-of-the-week-blue-jay|title=Bird of the Week: Blue Jay|publisher=Travis Audobon|date=July 17, 2024|access-date=October 21, 2025}}</ref><ref>{{cite web|url=https://www.audubon.org/field-guide/bird/blue-jay|title=Blue Jay|publisher=National Audobon Society|access-date=October 21, 2025}}</ref>

It builds an open cup nest in the branches of a tree; both sexes participate. The clutch may be two to seven eggs, which are blueish or light brown with darker brown spots. Young are [[altricial]], and are brooded by the female for 8–12 days after hatching. They may stay with their parents for one to two months.

The name ''jay'' derives from the bird's noisy, garrulous nature and has been applied to other birds of the same family, which are also mostly gregarious.<ref>{{cite book |last=Coues |first=Elliot |title=Key to North American birds |edition=5th |date=1890 |publisher=Estes and Lauriat |location=Boston, MA |oclc=469020022 |page=326}}</ref> Jays are also called ''jaybirds''.<ref name="missstate">{{cite web |title=Bird of the Month: Blue Jay|url=https://extension.msstate.edu/blogs/extension-for-real-life/bird-the-month-blue-jay|publisher=Mississippi State University Extension|last=Parker|first=Michaela |access-date=October 22, 2025}}</ref>

==Taxonomy==
The blue jay was first described as  ''Pica glandaria cærulea cristata'' in [[England|English]] naturalist [[Mark Catesby]]'s 1731 publication of ''Natural History of Carolina, Florida, and the Bahamas''.<ref>{{cite book|last=Catesby|first=Mark|author-link=Mark Catesby|title=Natural History of Carolina, Florida, and the Bahamas|edition=1st|date=1731|publisher=Royal Society House|location=[[London]]|page=87|url=http://dc.lib.unc.edu/cdm/compoundobject/collection/dmisc/id/1658/show/1487}}</ref> It was later described as ''Corvus cristatus'' in [[Carl Linnaeus]]' 1758 edition of ''[[Systema Naturae]]''.<ref>{{cite book|last=Linnaeus|first=C.|author-link=Carl Linnaeus|title=Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I. Editio Decima, Reformata| publisher=Laurentius Salvius|location=[[Stockholm|Holmiae]]|language=la| year=1758|volume=1|page=106|url=https://www.biodiversitylibrary.org/page/727076#page/124/mode/1up}}</ref> In the 19th century, the jay was described by [[France|French]] ornithologist [[Charles Lucien Bonaparte]] in 1838 as ''Cyanocorax cristatus'' in ''A geographical and comparative list of the birds of Europe and North America'',<ref>{{cite book|last=Bonaparte|first=Charles L.|author-link=Charles Lucien Bonaparte|title=A geographical and comparative list of the birds of Europe and North America|publisher=J. Van Voorst|location=London|year=1838|page=27|url=https://www.biodiversitylibrary.org/item/71558#page/39/mode/1up}}</ref> and given its modern scientific name ''Cyanocitta cristata'' by [[Hugh Edwin Strickland]] in 1845.<ref>{{cite book|title=Bulletin of the National History Survey, Issues 4-6|date=1900|publisher=Chicago Academy of Sciences|location=Chicago|page=120|url=https://books.google.com/books?id=x4YbAQAAMAAJ&q=Cyanocitta%20cristata%20Linnaeus%201758&pg=RA1-PA120}}</ref> The genus name ''Cyanocitta'' derives from the [[Greek language|Greek]] words ''kyaneos'' (blue) and the ''kitta'' and ''kissa'' (chattering bird, jay), and the term "blue chatterer" refers to the bright blue plumage of the head, nape, back, and tail of the bird. The specific name ''cristata'' (crested, tufted) derives from [[Latin language|Latin]] referring to the prominent blue crest of the jay.<ref name="Sandrock">{{cite book|last=Sandrock|first=James|title=The Scientific Nomenclature of Birds in the Upper Midwest|publisher=University of Iowa Press|year=2014|page=48|url=https://books.google.com/books?id=GsTpAgAAQBAJ&pg=PA48|isbn=978-1-60938-225-4}}</ref>

==Description==
[[File:102 Blue Jay.jpg|thumb|left|upright|[[John James Audubon]] drawing circa 1830s]] 
The blue jay measures {{convert|22|-|30|cm|abbr=on|0}} from bill to tail and weighs {{convert|70|-|100|g|abbr=on}}, with a wingspan of {{convert|34|-|43|cm|abbr=on}}.<ref name="CLO"/><ref name="Frysinger"/> Consistent with [[Bergmann's rule]], jays from [[Connecticut]] averaged {{convert|92.4|g|oz|abbr=on}} in weight, while jays from warmer southern [[Florida]] averaged {{convert|73.7|g|oz|abbr=on}}.<ref>{{cite journal |last=Jewell |first=S. D. |title=Weights and wing lengths in Connecticut Blue Jays |date=1986 |journal=Connecticut Warbler |volume=6 |number=4 |pages=47–49}}</ref><ref>{{cite journal | last1 = Fisk | first1 = E.J. | year = 1979 | title = Fall and winter birds near Homestead, Florida | journal = Bird-Banding | volume = 50 | issue = 3| pages = 224–303 | doi=10.2307/4512458| jstor = 4512458 }}</ref> There is a pronounced [[Crest (feathers)|crest]] on the head, a crown of feathers, which may be raised or lowered according to the bird's mood. When excited or aggressive, the crest will be fully raised. When frightened, the crest bristles outwards, brushlike. When the bird is feeding among other jays or resting, the crest is flattened on the head.<ref name="nero1991"/>

Its plumage is lavender-blue to mid-blue in the crest, back, wings, and tail, and its face is white. The underside is off-white and the neck is collared with black which extends to the sides of the head. The [[remiges|wing primaries]] and tail are strongly barred with black, sky-blue, and white. The bill, legs, and eyes are all black. Males and females are almost identical, but the male is slightly larger.<ref name="Frysinger"/><ref name="Madge"/> The black plumage on its nape, face, and throat varies extensively between individuals; it is believed to assist in recognition between individuals.<ref name="Frysinger" />

As with most other blue-hued birds, the blue jay's coloration is not derived from [[pigment]]s but is the result of light [[Interference (wave propagation)|interference]] due to the internal structure of the feathers;<ref>{{cite web |last=Carpenter |first=Anita |title=What Color is a Bluejay? |date=February 2003 |work=Wisconsin Natural Resources Magazine |url=http://dnr.wi.gov/wnrmag/html/stories/2003/feb03/jays.htm |access-date=October 21, 2012 |archive-date=July 31, 2018 |archive-url=https://web.archive.org/web/20180731134126/https://dnr.wi.gov/wnrmag/html/stories/2003/feb03/jays.htm }}</ref> if a blue feather is crushed, the blue disappears because the structure is destroyed. The actual pigment in its feathers is [[melanin]].<ref name="CLO"/> This is referred to as [[structural coloration]].

==Distribution and habitat==
[[File:Bluejay on branch.jpg|alt=A blue jay bird sits on a branch, surrounded by leafless tree branches.|thumb|Blue jay in Edmonton, Alberta, Canada in autumn.]]
The blue jay occurs from southern Canada and throughout the eastern and central United States south to [[Florida]] and northeastern [[Texas]]. The western edge of the range stops where the [[arid]] pine forest and scrub [[habitat]] of the closely related [[Steller's jay]] (''C. stelleri'') begins, generally in the eastern foothills of the [[Rocky Mountains]]. Recently, the range of the blue jay has extended northwestwards so that it is now a rare but regularly seen winter visitor along the northern US and southern Canadian [[Pacific]] Coast.<ref name="CLO" /> As the two species' ranges now overlap, ''C. cristata'' may sometimes [[hybrid (biology)|hybridize]] with Steller's Jay.<ref name="Rhymer" /> The increase in trees throughout the [[Great Plains]] during the past century due to fire suppression and [[tree planting]] facilitated the western range expansion of the blue jay<ref>{{cite journal|author=Smith GH|title=Range Extension of the Blue Jay into Western North America|journal=Bird-Banding|year=1978|volume=49|issue=3|pages=208–214|doi=10.2307/4512360|jstor=4512360|url=https://sora.unm.edu/sites/default/files/journals/jfo/v049n03/p0208-p0214.pdf}}</ref><ref>Tarvin KA, Woolfenden GE. (1999). "Blue Jay (''Cyanocitta cristata'')", no. 469. In: A. Poole (ed.). ''The Birds of North America Online''. Cornell Lab of Ornithology, Ithaca, New York.</ref> as well as range expansions of many other species of birds.<ref>{{cite journal | last1 = Livezey | first1 = KB | s2cid = 86276981 | year = 2009 | title = Range expansion of Barred Owls, part I: chronology and distribution | journal = American Midland Naturalist | volume = 161 | pages = 49–56 | doi=10.1674/0003-0031-161.1.49}}</ref><ref>{{cite journal | last1 = Livezey | first1 = KB | s2cid = 84426970 | year = 2009b | title = Range expansion of Barred Owls, part 2: facilitating ecological changes | journal = American Midland Naturalist | volume = 161 | issue = 2| pages = 323–349 | doi=10.1674/0003-0031-161.2.323}}</ref><ref>{{cite journal|author=Livezey KB|s2cid=85425945|title=Killing Barred Owls to Help Spotted Owls II: Implications for Many Other Range-Expanding Species|journal=Northwestern Naturalist|year=2010|volume=91|issue=3|pages=251–270|doi=10.1898/NWN09-38.1|jstor=40983223}}</ref> From 1966 to 2015, the Blue Jay experienced a population decline along the Atlantic coast, but a greater than 1.5% annual population increase throughout the northern part of its range, including [[Labrador]], [[Nova Scotia]], southern [[Quebec]], and southern [[Manitoba]].<ref>{{cite web |title=Blue Jay Cyanocitta cristata BBS Trend Map, 1966 - 2015 |url=https://www.mbr-pwrc.usgs.gov/bbs/tr2015/trend2015_v3.html |website=USGS |publisher=U.S. Department of the Interior |access-date=December 9, 2020}}</ref> 

The northernmost [[subspecies]] ''C. c. bromia'' is, subject to necessity, [[bird migration|migratory]]. It may withdraw several hundred kilometers south in the northernmost parts of its range. Thousands of blue jays have been observed to migrate in flocks along the [[Great Lakes]] and Atlantic coasts. It migrates during the daytime, in loose flocks of 5 to 250 birds. Much about their migratory behavior remains a mystery. Some are present throughout winter in all parts of their range. Young jays may be more likely to migrate than adults, but many adults also migrate. Some individual jays migrate south one year, stay north the next winter, and then migrate south again the next year. To date, no one has concretely worked out why they migrate when they do. Likely, it is related to weather conditions and how abundant the winter food sources are, which can determine whether other northern birds will move south.<ref name=eggeater/>

The blue jay occupies a variety of habitats within its large range, from the [[pine]] woods of Florida to the [[spruce]]-[[fir]] forests of northern Ontario. It is less abundant in denser forests, preferring mixed woodlands with [[oak]]s and [[beech]]es.<ref name=nero1991/> It has adapted to human activity very well, occurring in parks and residential areas, and can adapt to wholesale [[deforestation]] with relative ease if human activity creates other means for the jays to get by.<ref name=henninger1906/>

==Subspecies==
Four [[subspecies]] are generally accepted, though the variation within this species is rather subtle and essentially [[cline (population genetics)|clinal]]. No firm boundaries can be drawn between the inland subspecies. The ranges of the coastal races are better delimited.<ref name=Madge/>

{| class="wikitable"
|-
! Image !! Subspecies!! Common name !! Description !! Distribution
|-
|[[File:Blue jay in Central Park (16465).jpg|120px]] ||''Cyanocitta cristata bromia'' {{au| Oberholser, HC 1921 }} || Northern blue jay || The largest subspecies, with fairly dull plumage. Blue is rather pale. || Canada and northern United States. Type locality: [[Wooster, Ohio|Wooster]], [[Wayne County, Ohio]].<ref name="Oberholser">{{cite journal |last1=Oberholser |first1=Harry C. |author1-link=Harry C. Oberholser |title=The geographic races of Cyanocitta cristata |journal=The Auk |date=1921 |volume=38 |pages=83–89 |doi=10.2307/4074029 |jstor=4074029 |url=https://sora.unm.edu/sites/default/files/journals/auk/v038n01/p0083-p0089.pdf |access-date=October 25, 2024}}</ref>
|-
|[[File:Blue Jay Ash RWD5.jpg|120px]] || ''Cyanocitta cristata cristata''|| Coastal blue jay || The nominate subspecies, mid-sized and vivid blue. || Coastal USA from [[North Carolina]] to [[Texas]], except southern [[Florida]]. Type locality: southeastern [[South Carolina]].<ref name="Oberholser"/>
|-
|[[File:Cyanocitta cristata cyanotephra, Lubbock, Texas 2.jpg|120px]] || ''Cyanocitta cristata cyanotephra'' {{au|Sutton, GM 1935 }} || Interior blue jay || Mid-sized, quite dark blue on mantle contrasting cleanly with very white underside, broader white wingbar and tail tip.<ref name="Sutton"/> || Inland USA from SE Wyoming and Nebraska to west Kansas, Oklahoma and northern Texas, intergrading with ''C. c. bromia'' to the north. Type locality: [[Kenton, Oklahoma|Kenton]], [[Cimarron County, Oklahoma]].<ref name="Sutton">{{cite journal |last1=Sutton |first1=George Miksch |author1-link=George Miksch Sutton |title=A new Blue Jay from the western border of the Great Basin |journal=The Auk |date=1935 |volume=52 |pages=176–177 |doi=10.2307/4077201 |jstor=4077201 |url=https://sora.unm.edu/sites/default/files/journals/auk/v052n02/p0176-p0177.pdf |access-date=October 25, 2024}}</ref>
|-
|[[File:Cyanocitta cristata semplei, Broward, Florida 01.jpg|120px]] || ''Cyanocitta cristata semplei'' {{au|Todd, 1928}}|| Florida blue jay || The smallest subspecies, much like ''C. c. bromia'' in color. || Southern Florida. Type locality: [[Coconut Grove]], [[Miami-Dade County, Florida]].<ref name="Todd">{{cite journal |last1=Todd |first1=W. E. Clyde |author1-link=W. E. Clyde Todd |title=A new Blue Jay from Southern Florida |journal=The Auk |date=1928 |volume=45 |pages=364–365 |doi=10.2307/4076032 |jstor=4076032 |url=https://sora.unm.edu/sites/default/files/journals/auk/v045n03/p0364-p0365.pdf |access-date=October 25, 2024}}</ref>
|-
|}

==Behavior==
[[File:MerlinchasingBlueJay08.jpg|thumb|right|[[Merlin (bird)|Merlin]] chasing a blue jay]]
The blue jay is a noisy, bold, and aggressive [[passerine]]. It is a moderately slow flier (roughly {{Convert|32|-|40|kph|abbr=on|disp=or}}) when unprovoked.<ref>[http://www.tpwd.state.tx.us/publications/nonpwdpubs/young_naturalist/animals/animal_speeds/index.phtml Animal Speeds]. Texas Parks & Wildlife. Retrieved July 1, 2008.</ref> It flies with body and tail held level, with slow wing beats.
Its slow flying speeds make this species easy prey for hawks and owls when it flies in open areas. Virtually all the raptorial birds sympatric in distribution with the blue jay may prey upon it, especially swift bird-hunting specialists such as the ''[[Accipiter]]'' hawks. Diverse predators may prey on jay eggs and young up to their fledgling stage, including [[tree squirrel]]s, [[snake]]s, [[cat]]s, [[crow]]s, [[raccoon]]s, [[opossum]]s, other jays and possibly many of the same birds of prey who attack adults.<ref name= ADW>{{cite web|url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Cyanocitta%20cristata.html|title=ADW: Cyanocitta cristata: INFORMATION|work=Animal Diversity Web}}</ref>

The blue jay can be beneficial to other bird species, as it may chase [[predator]]y birds, such as [[hawk]]s and [[owl]]s, and will scream if it sees a predator within its territory. It has also been known to sound an alarm call when hawks or other dangers are near, and smaller birds often recognize this call and hide themselves away accordingly. It may occasionally impersonate the calls of raptors, especially those of the [[Red-tailed Hawk|red-tailed]] and [[red-shouldered hawk]]s, possibly to test whether a hawk is in the vicinity, though also possibly to scare off other birds that may compete for food sources.<ref name=eggeater/> It may also be aggressive towards humans who come close to its nest, and if an owl roosts near the nest during the daytime the blue jay [[Mobbing behavior|mobs]] it until it takes a new roost.<ref name=oiseauxnet2008/> However, blue jays have also been known to attack or kill other smaller birds, and foliage-roosting bat species such as [[Eastern red bat]]s.<ref name=auk>{{cite journal|doi=10.2307/4082327|jstor=4082327|url=https://sora.unm.edu/sites/default/files/journals/auk/v076n04/p0532-p0532.pdf|title=Blue Jays Attack a Red Bat|year=1959|last1=Clay|first1=William M.|journal=The Auk|volume=76|issue=4|page=532}}</ref> Jays are very territorial birds, and they will chase others from a [[bird feeder|feeder]] for an easier meal. Additionally, the blue jay may raid other birds' nests, stealing eggs, chicks, and nests. However, this may not be as common as is typically thought, as only 1% of food matter in one study was bird material.<ref name=eggeater/> Despite this, other passerines may still mob jays who come within their breeding territories.

[[File:C. c. bromia, in New York, NY.jpg|thumb|Blue jay in flight]]When a blue jay is agitated or angry, the blue crest atop its head will rise. It will lower when the bird is relaxed or calm.<ref>{{Cite web|url=https://www.freeweekly.com/2016/03/30/the-truth-about-blue-jays/|title=The Truth About Blue Jays – The Free Weekly|date=30 March 2016 |language=en-US|access-date=September 8, 2019}}</ref>

Blue jays, like other [[Corvidae|corvids]], are highly curious and are considered [[Bird intelligence|intelligent birds]]. Young individuals playfully snatch brightly colored or reflective objects, such as [[bottle cap]]s or pieces of [[Aluminium foil|aluminum foil]], and carry them around until they lose interest.<ref name=oiseauxnet2008/> Blue jays are confirmed to have engaged in tool use both in captivity and in the wild. Blue jays in captivity have been observed using strips of newspaper as tools to obtain food,<ref name=eggeater/><ref name=Jones/> while captive fledglings have been observed attempting to open the doors of their cages.<ref>{{cite web |url=http://db89.tumblr.com/post/6161461898/a-clever-blue-jay-fledgling-attempts-to-open-the |title=American Rivers |archive-url=https://web.archive.org/web/20131218082948/http://db89.tumblr.com/post/6161461898/a-clever-blue-jay-fledgling-attempts-to-open-the |archive-date=December 18, 2013}}</ref> A wild blue jay was observed using a piece of bark to aid in catching a spider.<ref>{{cite journal | doi=10.1080/15594491.2025.2464378 | title=Tool use by a wild Blue Jay ( ''Cyanocitta cristata'' ) | date=2025 | last1=Cash | first1=Lee C. | last2=Tarvin | first2=Keith A. | journal=The Wilson Journal of Ornithology | volume=137 | issue=2 | pages=276–283 | doi-access=free }}</ref>

==Diet==
{{Multiple image
| image1            = Blue jay - nut cracking.ogv
| image2            = Blue Jay 0461 (4487561501).jpg
| image3            = Blue Jay (45470334405).jpg
| caption1          = Cracking seeds
| caption2          = Eating peanuts
| caption4          = Eating a [[green anole]]
| image4            = Blue Jay, White Rock Lake, Dallas, TX imported from iNaturalist photo 17226391.jpg
| caption3          = Eating an insect larva
| total_width       = 800
| align             = center
}}
Blue jays are [[Omnivore|omnivorous]], but the [[Audubon Society]] estimates that 75% of their diet is vegetable matter.<ref>{{cite web |title=Blue Jay Cyanocitta cristata |url=https://www.audubon.org/field-guide/bird/blue-jay#:~:text=Omnivorous.,small%20fruits%2C%20sometimes%20cultivated%20fruits. |website=Audubon.org|date = November 13, 2014}}</ref> They have strong black bills which they use for cracking nuts, usually while holding them with their feet, and for eating corn, grains and seeds. Blue jays particularly love to eat [[peanut]]s in the shell.<ref>{{Cite web|url=https://www.g6consulting.ca/Blue-jays-love-peanuts-in-the-shell/|title = Blue jays love peanuts in the shell}}</ref> Its food is sought both on the ground and in trees and includes virtually all known types of plant and animal sources, such as [[acorn]]s and [[beech]] mast, [[weed]] seeds, [[grain]], [[fruit]], and other [[berry|berries]], peanuts, [[bread]], [[meat]], small [[invertebrate]]s of many types, scraps in town parks, [[bird-table]] food and rarely [[egg (biology)|eggs]] and nestlings.<ref name="eggeater" >[https://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Blue_Jay.html Blue Jay]. birds.cornell.edu</ref> Blue jays will sometimes [[cache (biology)|cache]] food, though to what extent differs widely among individuals.<ref>[http://www.allaboutbirds.org/guide/Blue_Jay/id AllAboutBirds.org – Blue Jay] The Cornell Lab of Ornithology</ref> Although seemingly contentious in their general behavior, blue jays are frequently subservient to other medium-sized birds who visit bird feeders. In [[Florida]], blue jays were dominated at feeders by [[eastern gray squirrel]]s, [[Florida scrub jay]]s, [[common grackle]]s, and [[red-headed woodpecker]]s, all of which were occasionally observed to aggressively prevent the jays from feeding.<ref name=eggeater/>

==Reproduction==
The [[mating season]] begins in mid-March, peaks in mid-April to May, and extends into July. Any suitable tree or large bush may be used for nesting, though an evergreen is preferred. The nest is preferentially built at a height in the trees of {{convert|3|to|10|m|ft|0|abbr=on}}. It is cup-shaped and composed of twigs, small roots, bark strips, moss, other plant material, cloth, paper, and feathers, with occasional mud added to the cup.

Blue jays are not very picky about nesting locations. If no better place is available – such as in a heavily [[deforestation|deforested]] area – they will even use places like the large [[Letter box|mailboxes]] typical of the rural United States.<ref name=henninger1906/> They also appropriate nests of other mid-sized songbirds as long as these are placed in suitable spots; [[American robin]] nests are commonly used by blue jays, for example.

Blue jays typically form [[monogamy in animals|monogamous]] pair bonds for life. Both sexes build the nest and rear the young, though only the female broods them. The male feeds the female while she is brooding the eggs. There are usually between 3 and 6 (averaging 4 or 5) eggs laid and [[avian incubation|incubated]] over 16–18 days. The young [[fledge]] usually between 17 and 21 days after hatching.<ref name=oiseauxnet2008/>

{{multiple image
| direction         = horizontal
| width             = 200
| image1            = Blue Jays nest.jpg
| caption1          = Nest in the top of a little pine
| image2            = Cyanocitta cristata MWNH 1384.JPG
| caption2          = Eggs, Collection [[Museum Wiesbaden]]
| image3            = Blue Jay Cyanocitta cristata Fledgling.jpg
| total_width       = 800
| align             = center
| image4            = Blue jay fledgling (53513).jpg
| caption4          = Juvenile, in July
| caption3          = Fledgling, in mid-June
}}

After the juveniles fledge, the family travels and forages together until early fall, when the young birds disperse to avoid competition for food during the winter. Sexual maturity is reached after one year of age. The oldest known wild, banded Blue Jay was at least 26 years, 11 months old when it was found dead after being caught in fishing gear. It had been banded in the Newfoundland/Labrador/Saint-Pierre et Miquelon area in 1989 and was found there in 2016.<ref>{{Cite web|url=https://www.allaboutbirds.org/guide/Blue_Jay/|title=Blue Jay Overview, All About Birds, Cornell Lab of Ornithology}}</ref> Another wild jay was found to have been around {{frac|17|1|2}} years old.<ref>{{cite web |title=Longevity Records Of North American Birds |publisher=U. S. Geological Survey: Bird Banding Laboratory |url=https://www.pwrc.usgs.gov/BBL/longevity/Longevity_main.cfm |access-date=December 24, 2012}}</ref> A more common lifespan for wild birds that survive to adulthood is around 7 years.<ref>{{cite web | url = https://www.canadiangeographic.ca/article/animal-facts-blue-jay | title = Animal facts: Blue Jay | date = July 26, 2006 | website = Canadian Geographic | publisher = The Royal Canadian Geographical Society | access-date = February 3, 2019 | archive-date = February 4, 2019 | archive-url = https://web.archive.org/web/20190204014621/https://www.canadiangeographic.ca/article/animal-facts-blue-jay }}</ref> Beyond predation and the occasional collision with man-made objects, a common cause of mortality in recent decades has been the [[West Nile virus]], to which corvids as a whole seem especially susceptible. However, despite several major local declines, overall blue jays have not seemed to have been depleted by the disease.<ref name=ADW/>

==Vocalizations==
Blue jays can make a large variety of sounds, and individuals may vary perceptibly in their calling style. Like other corvids, they may learn to mimic human speech. Blue jays can also copy the cries of local hawks so well that it is sometimes difficult to tell which it is.<ref name=George2003/> Their voice is typical of most [[jay]]s in being varied, but the most commonly recognized sound is the alarm call, which is a loud, almost [[gull]]-like scream. There is also a high-pitched ''jayer-jayer'' call that increases in speed as the bird becomes more agitated. This particular call can be easily confused with the chickadee's song because of the slow-starting ''chick-ah-dee-ee''. Blue jays will use these calls to band together to [[Mobbing behavior|mob]] potential predators such as [[hawk]]s and drive them away from the jays' nests.

{{Listen
| filename=Cyanocitta cristata - Blue Jay - XC86756.ogg
| title=Blue jay "rusty pump" calls (among gray catbird calls)
}}

Blue jays also have quiet, less noticeable calls which they use among themselves in proximity. One of the most distinctive calls of this type is often referred to as the "rusty pump" owing to its squeaky resemblance to the sound of an old hand-operated [[water pump]]. The blue jay (and other corvids) are distinct from most other songbirds for using their call as a song.

==In human culture==

===Fiction and folklore===
In old [[African-American folktales]] of the southern United States, the blue jay was a significant metaphysical creature. In some tales, the blue jay was credited with making the earth ''"when all de worl' was water"'' by bringing the first ''"grit"'' or ''"dirt."'' In other tales the blue jay was temporarily conscripted as a servant of the Devil, and would not be seen on Friday as it was gathering twigs to furnish hell's kindling and give fire to wicked men on Earth. Relieved from duty on Saturday, its song for the day was abundant and joyous.<ref name=ingersoll23>{{cite book |last=Ingersoll |first=Ernest |author-link=Ernest Ingersoll |title=Birds in legend, fable and folklore |publisher=Longmans, Green and Co. |location=New York |date=1923 |pages=[https://archive.org/details/birdsinlegendfab00inge/page/166 166]–167 |url=https://archive.org/details/birdsinlegendfab00inge |access-date=August 8, 2009}}</ref><ref>{{Cite book |last=Randolph |first=Vance |url=https://books.google.com/books?id=txnhppn0SrwC&pg=PA248 |title=Ozark Magic and Folklore |date=July 31, 2012 |publisher=Courier Corporation |isbn=978-0-486-12296-0 |language=en}}</ref>

An anthropomorphic blue jay named [[List of Regular Show characters#Mordecai|Mordecai]] is one of the main characters of the [[Cartoon Network]] animated television series ''[[Regular Show]]''.

===Mascots and symbols===
The blue jay is the [[List of Canadian provincial and territorial symbols|provincial bird]] of the province of [[Prince Edward Island]] in Canada.<ref>{{cite web |title=Provincial Bird |url=https://www.princeedwardisland.ca/en/information/executive-council-office/provincial-bird |website=Prince Edward Island |access-date=February 1, 2024 |date=May 26, 2015}}</ref>

The blue jay is also the official mascot for [[Johns Hopkins University]], [[Elmhurst University]], and [[Creighton University]].

The blue jay was adopted as the team symbol of the [[Toronto Blue Jays]] [[Major League Baseball]] team, as well as some of their [[Minor League Baseball|minor league]] affiliates. Their [[mascot]], [[Toronto Blue Jays mascots|Ace]], is an anthropomorphic blue jay.

==References==
{{Reflist|35em|refs=
<ref name=CLO>{{cite web|url=https://www.allaboutbirds.org/guide/Blue_Jay/|title=Blue Jay|publisher=Cornell Lab of Ornithology}}</ref>

<ref name=Frysinger>{{cite web|url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Cyanocitta_cristata.html|title=ADW: Cyanocitta cristata: INFORMATION|work=Animal Diversity Web}}</ref><!-- there is some more information here e.g. on predators and status -->

<ref name=George2003>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}}</ref>
* Goodwin, Derek & Gillmor, Robert (1976). ''Crows of the World'' (1st ed.) University of Washington Press, Seattle.
<ref name=henninger1906>{{cite journal |last=Henninger |first=W. F. |date=1906 |title=A preliminary list of the birds of Seneca County, Ohio |journal=[[Wilson Bulletin]] |volume=18 |issue=2 |pages=47–60 |url=http://sora.unm.edu/sites/default/files/journals/wilson/v018n02/p0047-p0060.pdf }}</ref>

<ref name=Jones>{{cite journal |last1=Jones |first1=Thony B. |last2=Kamil |first2=Alan C. |date=1973 |title=Tool-Making and Tool-Using in the Northern Blue Jay |journal=[[Science (journal)|Science]] |volume=180 |issue=4090 |pages=1076–1078 |doi=10.1126/science.180.4090.1076 |url=http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1066&context=bioscibehavior |pmid=17806587|bibcode=1973Sci...180.1076J |s2cid=22011846 |url-access=subscription }}</ref>

<ref name=Madge>{{cite book |last1=Madge |first1=Steve |last2=Burn |first2=Hilary |title=Crows and jays: a guide to the crows, jays and magpies of the world |date=1994 |publisher=A&C Black |location=London |isbn=978-0-7136-3999-5}}</ref>
<ref name=nero1991>{{cite web |url=http://www.ffdp.ca/hww2.asp?id=30&cid=7 |title=Blue Jay|publisher=Canadian Wildlife Service |access-date=August 9, 2009 |archive-url=https://web.archive.org/web/20090204094824/http://www.ffdp.ca/hww2.asp?id=30&cid=7 |archive-date=February 4, 2009 }}</ref>
<ref name=oiseauxnet2008>{{cite web|url=http://www.oiseaux.net/oiseaux/passeriformes/blue.jay.html|archive-url=https://web.archive.org/web/20070502082729/http://www.oiseaux.net/oiseaux/passeriformes/blue.jay.html|archive-date=May 2, 2007|title=Blue Jay}}</ref>
<ref name=Rhymer>{{cite journal |last1=Rhymer |first1=Judith M. |last2=Simberloff |first2=Daniel |date=1996 |title=Extinction by hybridization and introgression |journal=[[Annu. Rev. Ecol. Syst.]] |doi=10.1146/annurev.ecolsys.27.1.83 |volume=27 |issue=1 |pages=83–109|bibcode=1996AnRES..27...83R }}</ref>
}}

==External links==
{{Commons and category|Cyanocitta cristata|Cyanocitta cristata}}
* {{Wikispecies-inline|Cyanocitta cristata}}
* [http://www.allaboutbirds.org/guide/blue_jay/id Blue Jay ID, including sound and video], at Cornell Lab of Ornithology
* [https://web.archive.org/web/20100529193817/http://www.mbr-pwrc.usgs.gov/id/framlst/i4770id.html Blue Jay – ''Cyanocitta cristata'' – USGS Patuxent Bird Identification InfoCenter] archived May 2010
* {{InternetBirdCollection|blue-jay-cyanocitta-cristata|Blue Jay}}
* [https://web.archive.org/web/20210528202943/http://www.borealforest.org/birds/bluejay.htm Blue Jay at borealforest.org] archived May 2021
* [https://web.archive.org/web/20110106020639/http://www.flmnh.ufl.edu/wwwsounds/birds/hardy47sh.wav Blue Jay Bird Sound at Florida Museum of Natural History] archived January 2011
* [https://web.archive.org/web/20140416221712/http://www.suitable.com/fun/bluejays/index.html Photo essay of blue jay nestlings] archived April 2014
* {{VIREO|blue+jay|Blue Jay}}

{{Corvidae}}

{{Taxonbar|from=Q199758}}

[[Category:Cyanocitta]]
[[Category:Birds of North America]]
[[Category:Birds of Canada]]
[[Category:Native birds of Eastern Canada]]
[[Category:Birds of the United States]]
[[Category:Fauna of the Eastern United States]]
[[Category:Tool-using animals]]
[[Category:Birds described in 1758|Blue jay]]
[[Category:Articles containing video clips]]
[[Category:Animal taxa named by Carl Linnaeus|Blue jay]]
[[Category:Extant Piacenzian first appearances]]