page_title: Blue jay
section_title: Behavior
hierarchical_section_title: Blue jay / Behavior
caption_attribution_description: Merlin (Falco columbarius columbarius) chasing a Northern Blue Jay (Cyanocitta cristata bromia). Mount Auburn Cemetery, Massachusetts, USA.
context_page_description: The blue jay is a passerine bird in the family Corvidae, native to eastern North America. It resides through most of the eastern and central United States, although western populations may be migratory. Resident populations are also found in Newfoundland, Canada, while breeding populations can be found across southern Canada. It breeds in both deciduous and coniferous forests, and is common in residential areas. It 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, and plumage does not vary throughout the year. Four subspecies of the blue jay have been recognized.
  The blue jay mainly feeds on nuts and seeds such as acorns, soft fruits, arthropods, and occasionally small vertebrates. It typically gleans food from trees, shrubs, and the ground, though it sometimes hawks insects from the air. Blue Jays can be very aggressive towards other birds; they sometimes raid nests, and have even been observed decapitating other birds. Like squirrels, blue jays are known to hide nuts for later consumption.
context_section_description: The blue jay is a noisy, bold, and aggressive passerine. It is a moderately slow flier (roughly 32–40 km/h (20–25 mph)) when unprovoked. It flies with body and tail held level, with slow wing beats.
  Due to its slow flying speeds, this species makes easy prey for hawks and owls when flying 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 fledging stage, including tree squirrels, snakes, cats, crows, raccoons, opossums, other jays and possibly many of the same birds of prey who attack adults.
  The blue jay can be beneficial to other bird species, as it may chase predatory birds, such as hawks and owls, 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 and red-shouldered hawks, possibly to test if a hawk is in the vicinity, though also possibly to scare off other birds that may compete for food sources. 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 mobs it until it takes a new roost. However, blue jays have also been known to attack or kill other smaller birds, and foliage-roosting bat species such as Eastern red bats. Jays are very territorial birds, and they will chase others from a 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. Despite this, other passerines may still mob jays who come within their breeding territories.
  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.
  Blue jays, like other corvids, are highly curious and are considered intelligent birds. Young individuals playfully snatch brightly coloured or reflective objects, such as bottle caps or pieces of aluminum foil, and carry them around until they lose interest. While not confirmed to have engaged in tool use in the wild, blue jays in captivity have been observed using strips of newspaper as tools to obtain food, while captive fledglings have been observed attempting to open the doors of their cages.
caption: Merlin chasing a blue jay
exif: {"Image Make": "Canon", "Image Model": "Canon EOS 30D", "Image Orientation": "Horizontal (normal)", "Image XResolution": "96", "Image YResolution": "96", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop Elements 6.0 Windows", "Image DateTime": "2009:02:24 23:37:12", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "228", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "1054", "Thumbnail JPEGInterchangeFormatLength": "5099", "EXIF ExposureTime": "1/1250", "EXIF FNumber": "28/5", "EXIF ExposureProgram": "Program Action", "EXIF ISOSpeedRatings": "400", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2008:10:26 16:24:20", "EXIF DateTimeDigitized": "2008:10:26 16:24:20", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "84277/8192", "EXIF ApertureValue": "162885/32768", "EXIF ExposureBiasValue": "0", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "400", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "773", "EXIF ExifImageLength": "466", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "928", "EXIF FocalPlaneXResolution": "233600/59", "EXIF FocalPlaneYResolution": "233600/59", "EXIF FocalPlaneResolutionUnit": "2", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard"}