. . . Fall 1999
Story and photos by John Ivanko Have you ever seen a bluebird? Most of us haven't,
nor even could, at least not until recently. The rebounding bluebird
populations have made seeing this popular songbird increasingly likely,
especially along rural roadsides or in parks and other open spaces.
To see a pair of bluebirds is mesmerizing, especially the iridescent
blue-colored male Eastern Bluebird when in flight on a bright summer day,
busy at work feeding a brood of nestlings. Like a bold brush stroke of
blue color, the male dives from a tree to the lawn to snatch an insect on
the ground.
The bluebirds' color was so remarkable to Henry David Thoreau that he
felt compelled o describe this species' coloring as "carrying the sky
on its back." An insightful description since the bluebird's blue
color does, in fact, come from light waves scattered by the structure of
their feathers, not from blue pigment in their feathers-a blue suncatcher,
so to speak. That's why a bluebird appears gray on an overcast day. But there is a lot more to bluebirds than their color and tender
demeanor which contributed to their predominant place in American culture,
for bluebirds have become a mainstay of Hallmark greeting cards and show
up in more songs that any other songbird.
The Eastern Bluebird is the state bird for Missouri and New York; the
Mountain Bluebird holds this distinction for Nevada and Idaho. The male
Eastern Bluebird's brilliant blue back and rust-colored breast and the
more subdued blue of the Mountain Bluebird, with a white, rather than
rust-colored, breast, has resulted in their starring role in numerous
poems and artwork. The Native Americans have folktales about how bluebirds
received their color.
There are two different kinds of bird colors: pigment-based, and
structural. White, blue, green, iridescent and ultraviolet birds derive
their color from the structure of their feathers, specifically from the
protein keratin in their feathers (also the chief constituent of hair,
nails, horns and hoofs).
In the case of the bluebirds (and Blue Jay), the keratin reflects and
scatters incoming light, reflecting the shortest wavelength (blue). The
blue of the sky results from a similar scattering of light in the
atmosphere.
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One
of the three bluebird speciesÐEastern Bluebird, Mountain Bluebird or
Western BluebirdÐis likely to be seen almost anywhere on the continent
where wide open grassy spaces are present, and in several states where
their ranges overlap, two species might be seen.
Bluebirds,
As
a bluebird landlord, one who provides nest boxes for these species to nest
in, I'm awestruck by their seeming ability to recognize us. Bluebirds will
often return to the same nesting site, year after year.