What can I feed the cardinals to make them redder?

Hi My visiting Cardinals aren’t looking as bright or vivid recently. Is it the long hard winter? Or can I add something to my feeder to help them regain the splendor that I remember? Bill

The Northern Cardinal has a varied diet and the best way to help the birds develop brighter plumage is to create a habitat with lots of natural fruits and berries.

Cardinals as well as other red feathered birds get their red plumage from pigments called carotenoids. Birds can’t synthesize carontenoid pigments but must obtain them from their food like wild grapes, apples, raspberries, dogwood fruits and various seeds.

Normal male Northern Cardinals exhibit individual variation in coloration, with their plumage ranging from pale orange to bright red. I can’t find any experiments done with cardinals, but I did read one study where male house finches that were fed more foods containing carotenoids at the time of molt had brighter, redder plumage.

So there is nothing you can add to the feeder to make a cardinal’s feathers redder instantly. Cardinals undergo an annual molt in the late summer and fall at which time males acquire their plumage coloration for the following year. Right now cardinals are eating wild fruit seeds, weed seeds and buds from a variety of trees.

At the feeding stations during cold weather the birds tend to prefer seeds that provide the most calories. The U.S. Fish and Wildlife Service published a landmark study of bird food preferences in 1980 for several bird species and found cardinals exhibited the greatest preference for oil sunflower, peanuts, safflower, and millet. They avoid buckwheat, cracked corn, milo, oats, wheat, nyjer, canary, flax, rapeseed, and rice.

A cardinal's food habits in the north consists of more than 75% plant material from November to April. From May to October it changes to about 50% plant and the rest consists of animal matter predominately from insects, including beetles, grasshoppers, crickets, butterfly and moth larvae, cicadas, treehoppers, leafhoppers, and dragonflies.

Another study done by the Ohio State University found that juveniles during late summer are less well nourished than adults. Your cardinal may have been born late in the season. Newly independent young cardinals are less efficient foragers than adults which may result in a duller red color.

I hope that helps, Sarah

My gosh what an explanation- Thanks Bill

If your interested, click HERE to see the Kentucky Ornithological Society's pictures of a yellow Northern Cardinal with a link to a paper about the carotenoid pigments in a mutant cardinal.