Brian Jobson sent the following letter
(response sent from mmalle@cartalk.com).
To the GREAT Group of Car Talk,
I was listening to the January 18 show in Connecticut and heard a guest ask about the effects of color on the targeting of birds.
First and most important is that I am clueless as to the biological or instinctive reasons for this effect, but I, too, have seen it.
I have a 1992 Cherokee wagon (white) and a 1991 Taurus (dark green). From April to mid-December the Jeep is the principal target of birds and the Ford is by far the secondary.
I think the naturalists feel that the migatory patterns of birds are driven by temperature or depleting food supplies, but I think your caller may have found the real reason for bird migration. It has to be the "White Effect." This is a hormone that triggers the “Poop Reaction” when a bird sees a large area of white. Therefore, if birds did not migrate and found themselves in an entire region of white (from snowfall), the result may be one uncomfortable bird. This must be the true driving instinct for migration.
Just wanted to share my thoughts. Great show--I don't stop smiling throughout the program. Thanks for the good feelings.
Best regards,
Brian Jobson
