Thursday, February 4, 2010

I think Blue Jays are Colts Fans!

The Indianapolis Colts are going to the Super Bowl! And everyone in Indy is feeling the excitement. Today, we had some rowdy Colts Fans mob our feeders! "COLTS, COLTS, COLTS!" they cheered, chasing the Cardinal fans away from the peanut feeder. The jays honestly think the peanuts are their personal stash. No wonder the Blue Jay is one of my favorite birds. Always decked out in Colts' Blue, my preferred color, jays have spunk and spirit. They will show up at the feeder and challenge other birds to just try and take some of their food. They are top dogs and not afraid to let all the other birds know it.

Blue Jay photo by Charles Creamer.

Its scientific name of Cyanocitta cristata means "crested blue chattering bird". This description is very appropriate since the Blue Jay is a very noisy bird and can imitate almost anything. I have heard them imitate car alarms, bells, cats, squeaky gates, growls and even hawks. Being a member of the crow family, they are also very smart birds. There is one account in an article by R.W. Loftin where a Blue Jay imitated a hawk to frighten a grackle and cause it to drop its food. The jay swooped down and snagged the food before the poor grackle knew what had happened!

Jays exhibit another intelligent behavior called "anting". Blue Jays will grasp ants by the head or thorax, then wipe the ants' abdomens on their feathers. The ants produce a chemical called formic acid as a defense. This formic acid acts as an insecticide and helps get rid of mites, fungi and insects that can damage the birds feathers.

Blue Jay with acorn. Photo by John Howard.

Jays have an important role in the environment. They are feathered foresters. They will cache or store acorns in soft ground and cover them with leaves. They don't recover all of them, so they help grow many new oak trees and replenish our forests.

You've got to love a bird with such brilliant blue feathers, a color that is not often found in nature. It is a handsome bird that is especially stunning when it has just freshly molted its feathers. Such a brilliant Colts' blue. Stunning! But a fascinating fact is the feathers aren't really blue. There is no blue pigment in the feathers. The pigment found in the feathers is actually a gray-brown.


Yep, it's true. There are two ways feathers can produce colors. One way is called pigment color and the other is structural color. Pigment color comes from chemicals that are found in the feather. Pigment color will produce the same color no matter what angle the feather is viewed. One example of pigment color is carotenoids that produce colors of yellow, orange and red and come from the plant materials that the birds eat. Another is melanin which produces black, gray and brown color that are found in sparrow's feathers and produce a glowing tan on our skin in the summer.

Structural colors, or schemochromes, are a little more complicated. In a jay's feathers, the pigment melanin produces a brownish-gray color. Over that is a layer of keratin that contain tiny air cavities that are almost microscopic. Keratin is the fibrous protein that forms hair, nails and feathers. These air cavities found in the feathers scatter the light in such a way as to produce the blue color. The feathers appear blue for the same reason an oil slick appears blue. The blue in oil slicks and feathers results from differences in the distances traveled by light waves that are reflected off of each other. Richard Prum of Yale University did studies on this and called the process constructive interference. A side note, the green color in feathers are produced when yellow pigment is present along with the air cavities that cause the blue color.
Anyway you look at them, jays are fascinating and beautiful creatures. Glad they are around to root our Colts on to victory! GO COLTS!