Wednesday, July 21, 2021

Eastern Bluebird and the Color of Blue

 

Bluebird and Blossoms

There is no blue pigment in birds-
all blue color is produced by the microscopic structure of the feathers.  If you find a blue feather, you will notice that it is only blue on one side, and it looks drab brownish when light shines through it.  The bluebird's color relies on the same physical principles as iridescent hummingbird feathers, in which a coherent scattering of light reinforces some wavelengths and diminishes others, but the structure behind it is quite different.  Instead of multiple flat layers of material to reflect light, bluebirds have a spongy layer filled with tiny air pockets and channels.  These air pockets are all about the same size, and together they produce a patterned structure with the correct intervals to match the wavelength of blue light.  Waves of blue light scattered from one air pocket will be in phase with waves of blue light from some of the other air pockets.  Light of other wavelengths will be out of phase and mostly invisible.  Because the air pockets are evenly distributed throughout this spongy layer, the effects on light traveling in any direction are the same.
(From: What It's Like To Be A Bird  by
David Allen Sibley)

Hello friends!
Here is an original pastel painting on paper fresh off the easel of an Eastern Bluebird.  These birds can be seen in Southeast Arizona during migration as well.  I remember a birding excursion that my husband planned that took us to this region.  Up at the crack of dawn daily, we ventured out with binoculars and a packed lunch early to avoid the heat of the desert midday.  The vacation included an upgrade to a convertible which was a delightful surprise.  My husband introduced me to the world of birds and birdwatching.  I now find myself most attracted to the rendering of these feathered friends above other genres, and thus I embark on a commitment of weekly renderings of birds I've seen and studied with an accompanying blog post to share in the joy of art and birds.

This piece is available on my website:

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