Image via Wikipedia
Why are Cardinals so red and Goldfinches so yellow?
When I first hear that diet helped make Cardinals red, I found it hard to believe. So I decided to research the subject. I e-mailed the Cornell Lab of Ornithology public information section as well as googled the question. What I found is that diet does indeed influence the color; not only male Northern Cardinals but also male American Goldfinches. Carotenoid pigments in the diet affect bird color
Researchers have discovered that Cardinals fed a diet with no red pigments resulted in their color becoming a much paler red. When Goldfinches were fed a diet with more red pigments they became a more orange color. To read about the research go to: The Influence of Carotenoid Acquisition and Utilization on the Maintenance of Species‐Typical Plumage Pigmentation in Male American Goldfinches (Carduelis tristis) and Northern Cardinals (Cardinalis cardinalis)
RSS - Posts
Makes sense. My aunt used to breed red-factor canaries and when they molted she would change their diet so their new feathers would come in more reddish-orange.
By: entire leaves on April 11, 2011
at 9:36 AM