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Blue Jay Facts

Scientific name: Cyanocitta cristata
Length:  8 - 12 inches long:
Weight:  average 3 oz
Coloring:  bright blue on top, whitish gray on belly & chin; black around neck; wings & tails are blue with black & white bands; eyes, bills, legs & feet are black
Habitat:  woodlands with wide clearings; backyards and city parks
Range: native to the Nearctic region; also found in southern Canada & States east of the Rockies
Food: omnivore - fruits, nuts, seeds, insects, mice, frogs & sometimes eggs of other songbirds
Mating:  monogamous, life-long mates
Reproduction:  3-6 eggs of various colors; incubated 17-18 days; males feeds females while incubating; young leave nest after two months
Predators: falcons, hawks & owls; nestlings preyed on by cats, raccoons, snakes, squirrels and other large birds
Lifespan: average life of 7 years
Conservation concerns:  population is on the rise, status is safe

The Blue Jay is hard to miss whether against a backdrop of snowy branches or surrounded by lush green leaves. With its various hues of brilliant blue feathers, how could it not stand out? The bird's other distinguishing characteristics include wings barred in black, blue and white; black eyes, bill and three-toed limbs; and a black collar around its neck towards the tips of its crested head.

What's amazing about the coloration of the Blue Jay is that it isn't really blue. Like other blue birds, its coloring is not derived from  pigments, but by structural coloration - or the result of light refraction due to the internal structure of the feathers. This can be proved by crushing a feather; once destroyed the blue disappears. 

Though very beautiful, Blue Jays are rarely favorites among birders and homeowners. In fact, this bird has developed a bad reputation - one that may not be so deserved.

Not Necessarily a "Bad Egg"

Blue Jays are notorious for being a malicious beast in a pretty little bird body. Often called a thief and murderer,  many people dislike the Blue Jay as it is known to eat the eggs and nestlings of other birds. However, according to the Cornell Lab of Ornithology, a study on Blue Jay feeding habits has shown that only 1% of jays had any evidence of eggs or young birds in their stomachs.

This isn't to say that Blue Jays aren't aggressive. They are incredibly protective over their young and are willing to attack large predators - including humans - when intimidated by their presences. What is even more interesting is how a 'gang' of jays will cooperatively attack or mob an intruder in order to protect their offspring. Unfortunately many people will still regard Blue Jays as nest robbers instead of the intelligent birds that they are.

Not everyone dislikes the Blue Jay and their inherent antics. One of their biggest redemptive qualities is their role in oak tree regenerations. While they cache seeds and nuts from many plants, blue jays prefer acorns and can stuff up to 6 in their throat at once.  Blue jays stash such an abundance of food that they only recover 40 percent of their cache.  Doing their part for conservation, the blue jay is the poster child for regenerating the mighty oak forests.

More Interesting & Fun Facts

• The Blue Jay's  genus name Cyanocitta means blue chattering bird, and the species name cristata means crested.
• The most commonly recognized sound for the Blue Jay is its alarm call - a loud, shrill 'jaaay' for which it is named.
• The Blue Jay can mimic the calls of various other birds causing even the most experienced birder to take a second listen. This is common in most  jays.
• Like other crested birds, Blue Jays can raise or lower their crown of feathers depending on their moods. When relaxed of feeding, the crest flattens to the head. If excited, then it rises forward. When scared, the crest bristles outward.
• The migration of Blue Jays isn't well understood. Some jays stay in an area all winter long while others make the journey towards warmer climates. Yet those that migrate south one year don't necessarily migrate the next winter. Research is still being done on why Blue Jays migrate when they do.
• Blue Jays are known to be monogamous, life-long mates. Relationships only end in death.
• The most similar species in the Blue Jay's range is the Steller's Jay. Occasionally these two species will interbreed and produce hybrid jays.
• Blue and Steller's Jays are also the only jays in the western hemisphere that use mud when constructing their nests.