Q. Why is my cardinal bald?

 

A. I've had several people stop by the store on Saturdays recently and ask about male and female cardinals having an extremely bad hair day. (See photo of a bald female cardinal below.) As with many questions about the natural world there is no single, simple answer. 

 
To understand bald headed birds we ought to begin with a basic understanding of the molting process. Once a feather is full grown it loses it's blood supply. Without nourishment it cannot be repaired so it must be replaced. Every bird gets a new set of feathers every year. This usually takes place after breeding season. Adult birds gradually lose all their feathers and they are gradually replaced by late September. Juvenile birds molt in their first fall but replace only their body and head feathers. Wing and tail feathers aren't replaced until the following year.

 

A couple more things, If a feather is accidentally pulled out, a new one will grow right away regardless of time of year. All birds have a late summer molt. Some species (mostly finch) have a spring molt when they switch to their breeding plumage. The goldfinch is an obvious example.

Body feathers can sometimes be lost all at one time in patches so all birds have some bald spots (like the top of my head). Among the jays, cardinals and grackles there are some individuals who lose all of the feathers on their head at the same time. Laura Erickson is an old friend that's now at Cornell Ornithology and she has written about having two jays in captivity that could not be released after rehab. She witnessed their annual molt for eight years. One lost its head feathers gradually every year as do the majority of birds. The other blue jay in the same enclosure lost all of its head feathers at the same time every year.

 
This was a healthy blue jay with no evidence of mites and the other blue jay in the same cage had the same environment, same food and the same lack of mites, but molted in the usual way. We have two birds in the same cage and one molts its head feathers gradually and the other drops all of them at the same time.

Last on the list of possible causes of bird baldness are dietary deficiency, an infestation of feather mites or disease of some kind. This may be the reason why a cardinal would lose it head feathers this far ahead of the normal molt. Feather mites are not a long term threat to the bird's health.

 

It seems there are significant individual differences in the way birds lose their head feathers during a molt. While the majority of cardinals lose their head feathers gradually some it seems lose all their head feathers simultaneously. There is no cause; it is just the way a particular bird molts.

 

Q. I've got seed piling up under my feeder, why are birds so picky?

A. Birds are programmed to eat certain foods. The seed you are offering doesn't fit any bird's feeding program. Filler seeds are added to seed mixes to make them appear cheaper than they really are. Rice, buckwheat, milo (sorghum), red millet and grain products are examples of seeds that are added simply to add weight to the bag since no local birds eat them. [If half the seed in the bag is inedible it is really twice the price you think you are paying.]

 

One exception to this is white millet. Juncos are the most common bird in North America. Millet is eaten only by ground feeding birds like juncos. It's possible that you don't have enough ground feeding birds in your neighborhood once the juncos head north to consume all the millet in your mix. Switching to a mix with less millet until September will correct this problem.