Blue Jays
This article was run as a part of Jan's birding column in the Hutchinson Leader.
Friend or foe?
We are all familiar with the raucous, in your face blue jay, Cyanocitta cristata. Some of us love them, some of us hate them. Those who love them see their striking beauty and playfulness. Those who hate them see an aggressive, opportunistic predator that eats the eggs and young of other birds.
Blue jays are members of the Corvidae family, which consists of medium sized perching birds with rounded tails and wings. They have scaly legs and bristle like feathers that cover their nostrils. Other members of this family include Gray Jays, American Crows, and Ravens. Its members eat pretty much anything and are masters at food locating tasks. This family is highly susceptible to the West Nile virus.
Their beautiful blue color is the result of structural coloration. Like other blue colored birds, the internal structure of the feathers causes light to reflect, resulting in the color blue. If you were to crush the feathers, the color would disappear and you would be left with a grayish powder.
Blue jays are very curious and intelligent. Juvenile jays love to play, and are attracted to brightly colored and shiny objects. They will carry them around in their bills until something else piques their interest. Captive jays have been observed using strips of newspapers as tools to reach food that has fallen outside of their cage.
Their preferred habitat is the edge of mixed deciduous forests, especially oak forests. Human development has actually helped the population of these birds, as fragmentation of forests has led to an increase in the bird's ideal habitat where field and forest meet. Their presence may have an effect on other bird populations, but studies have shown only 1% of jays have the remains of eggs or nestlings in their stomach.
Blue Jays have four main calls. The “jeer” is used to call together a group or when mobbing a potential threat such as a human or owl. This call alerts other jays as well as small birds to danger. Their “pumphandle” call consists of clear musical whistles that sound like an old water pump or squeaky gate. They will engage in a peculiar bobbing of their body while making this call. The contact call is a soft sort of clucking noise made by pairs when foraging together or interacting with other pairs. Their “rattle call” is a series of fast, raspy clicks, similar to a cat purring.
Blue Jays are also great mimickers. I have often been fooled into thinking a Red-Shouldered or Red Tailed Hawk was in the yard, only to realize it was a Blue Jay. Although scientists are not sure why jays mimic the hawks, they hypothesize that it warns other jays of the presence of a hawk or deceives other species into believing a raptor is present.
The Blue Jay is monogamous and mates for life. The pair interacts by nudging each other, handing twigs to each other, and “kissing” by touching bills. They begin building their nest in April. They are not picky about the site, but will choose an evergreen if available. Trees or large bushes are also acceptable. In deforested areas, they may use mail boxes. The cup shaped nest is composed of twigs, roots, bark, and other plant material. Occasionally they will use the nests of other birds such as robins.
The male feeds the female during incubation. After 16-18 days, the 4 to 5 eggs will hatch. Both the male and female feed the babies, which fledge after 17 to 21 days. The family will stay together until early fall, when the young disperse to eliminate competition for food in the winter.
Blue jays are easily attracted to feeders, particularly platform feeders or feeders with trays. Most people see blue jays as aggressive, for when a noisy, gregarious group flies in, smaller birds will scatter. In reality, they are often bullied by other birds such as Common Grackles, Red Bellied Woodpeckers, Red-headed Woodpeckers, Mourning Doves, and even Northern Cardinals.
Blue Jays’ favorite food is peanuts, either in or out of the shell. People are amazed at their appetites as they gobble up peanut after peanut. What they do not realize is that the Blue Jays have a pouch in their throat and are merely holding the seed to store, or “cache” later. They will place the peanuts with foods found in the wild, such as acorns and other tree seeds, in crevices, behind bark, in the ground, and anyplace else it is safe from marauders. Their amazing memories allow them to find nearly all these stashed foods, but the missed seeds help to assure forest regeneration.
The debate will go on. Is the Blue Jay a friend or foe? After years of observation, I am convinced they are wonderful visitors to my yard. I welcome them with open arms and full feeders.
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