The Case of the Bald Birds

(This column first appeared in the September 14, 1998 Buffalo News.)

    The first call came in mid-August.

    "Are there any songbirds that have no feathers on their heads?"

    Over the years I have fielded so many inquiries that most now are repeats. But this was something new to me. A bald songbird?

    There are, of course, birds with no head feathers: our turkey vulture is one. The black vulture, a southern species rarely seen here, is another. So too is the California condor, now recovering from near extinction in the far west with the assistance of zoo-bred and released birds.

    But no bald songbirds.

    "We have one coming to our feeder. He's out there now. He looks just like a male cardinal except for the head, which is completely bare."

    I was stumped. All I could do was promise to look into the matter.

    Within minutes Noreen Olek called. Noreen and her husband Mike are two of our finest regional animal rehabilitators. They had received a similar inquiry, but this time it concerned three bald birds at the same feeder: another cardinal, a blue jay and an unidentified blackbird. Mike forwarded a picture of the cardinal, its purple head so ugly I could hardly look at it.

    Here it is: see what you think!

    I called Art Clark, vertebrate zoology curator at the Buffalo Museum of Science. This was unusual for him as well. He and I both searched the literature but found little help there.

    The four of us -- Art, Mike, Noreen and I -- came up with possible causes of this aberration. Unfortunately, each had shortcomings.

(1)  Something wrong in the molting process. John Terres in "The Encyclopedia of North American Birds" points out that molts usually replace feathers in waves so that bare spots rarely appear. This process might have malfunctioned. But many birds at once?

(2)  Disease. We found none with this characteristic.

(3)  Feather mites. Why then are only the heads affected?

(4)  Feather-picking. Some birds, especially crows, peck head feathers from others. But they usually attack their own species.

(5)  A feeder entrance rubbing off head feathers. None was found nearby.

    Until recently, that is where the matter would have ended. However, today we have an effective new resource -- the Internet. I posted a description of our dilemma together with a request for assistance on the Internet mail group, Birdchat. Through this medium my message was carried immediately to 1300 ornithologists around the world.

    Among the many responses, most told of personal experiences with this phenomenon. For example, Julie Stielstra of Illinois wrote, "This time every year this comes up. I've been laughing at a totally bald blue jay, a mutant-punk grackle with a Mohawk and a very pathetic looking cardinal with a little plume on a bald head at my feeder." (Note the remarkable coincidence of her species with those reported to the Oleks.)

    But two respondents gave us our answer. Mark Monroe, biologist at Hawk Mountain Sanctuary in Pennsylvania, wrote that it was indeed a mite infection and that it would not affect the next molt. And Susan Thuener -- quite appropriately of Mohawk, New York -- wrote, "The head is the one vulnerable spot on the bird that it cannot reach to preen."

    And so our mystery is solved. Seasonally, a few birds are attacked by feather mites, tiny arthropods whose feeding destroys feather shafts. Normally, the birds would divest themselves of these mites by preening, but birds cannot effectively preen their own heads. Once the mites have destroyed their food source on the birds' heads, they must either move on to a new victim or place themselves in jeopardy on another area of their host's body.

    We close our file on The Case of the Bald Birds.

Credit for the photograph of the bald cardinal goes to Marguarite McGinnis of Buffalo who took the picture in Batavia, Illinois.

    Well, not quite.

    My column needs to tell a brief story and reach a kind of closure so I left the matter resolved, but there is clearly more to the story. In particular, not everyone agrees with this assessment -- what else is new? -- and I offer here some comments by other observers. (Not all of the many informative messages I received are posted and some are posted only in part. I apologize to all who may feel that I have done violence to their views. If you feel especially put upon, please contact me and I will edit your message.)

Sherry Goldsmith, Los Angeles, CA: I don't think it is necessarily an either/or situation - either all bald birds are molting or all bald birds have mite or nutritional problems. Some birds may be bald because they are molting, others birds may be bald because they have mites or nutritional deficiencies, and yet other birds may be bald because of a combination of conditions.

    An example, I believe, is a scrub jay I was friends with for several years when I worked in the concrete canyons of the high-rise Century City area of Los Angeles. I called him Scruffy because, well, that was what he was - almost totally bald on his head and neck and totally bedraggled feathers elsewhere. He was also rather listless and "depressed" for a scrub jay, sitting huddled on a branch for long periods of time. He looked and acted like that for the first several months I knew him (I met him in about July or August), until I finally stopped at a pet store one day and got the best, most complete avian supplement I could find, then got some mealworms from a fishing tackle shop. Each day I gave him several mealworms to which I had added a drop of the supplement. Within a week or two he started to make a dramatic improvement and after about a month had become a beautifully sleek and energetic scrub jay. I continued to offer him mealworms and raw pinon nuts, all of which he eagerly accepted, and he went on to acquire a mate the next spring and successfully nest twice without ever again displaying any feather problem.

    This of course is purely anecdotal evidence, but I'm convinced that in Scruff's case, the poor feathering was basically due to dietary deficiencies - in his very marginal urban environs, I suspect he was reduced to scavenging too much people junk food from the local fast food outlets.

Matt Fain, Carbondale, IL: Only in the past couple of years have I been noticing such extensive feather loss in cardinals as well. I am familiar with the usual scruffy look during molt. I am not convinced that this phenomenon is entirely due to molt, although the condition may be made even more noticeable in the fall because of it. I don't think they're mutually exclusive possibilities. [speculation mode: on] Birds with heavier parasite load could turn "balder" than their not-so-infested neighbors during molt. [speculation mode: off]

    I have a pair of cardinals in the yard this summer that both have this condition. The male has been bald since April; the female since sometime in May. That's months! So I also would like to know more about what is going on.

Liz Day, Indianapolis, IN: The female cardinal that I saw became progressively balder over the course of a few months; by breeding season, her head was completely featherless. There must be more than one kind of baldness going on.

Lyn Atherton, Tierra Verde, FL: I have never seen a completely "bald" wild bird whose baldness wasn't related to its post-breeding molt, but I'm not insinuating that it couldn't possibly happen for other reasons. Perhaps the "baldness" is seen more often in individuals breeding in hotter climates. An unusually hot breeding season in a normally cooler climate may cause some individuals in that area to become bald during that particular season.

    Losing head feathers during the post-nuptial molt is a normal process in some species including cardinals, Blue Jays and Common Grackles. The fact that a vet gave medicine for this condition because he thought the cause was mites and dry skin indicates he needed to take a basic ornithology course! After a week or so the bird would have had a "normal appearance" even without medication. (Hope the office visit and medication weren't too expensive!)

Art and Hanna Richard, Ingram, TX: As a bird bander I have captured many Cardinals and Blue Jays with severe head molt. I took every one of those birds, held them over a white tissue, rubbed their heads, and examined the tiny matter that fell to the tissue with a hand lens. I, personally, have never found feather mites in the head area but did find tiny particles of quills. For some reason, all the feather mites I have found were on the body and/or wing feathers.

Liz Day, Indianapolis, IN: Wow. That's persistence! Perhaps the mites left the head after the feathers were all gone and moved to the neck?

Carolyn Hall, Bassett, NE: Gerry, a friend here in Nebraska found a wren attacking a nest of almost grown baby eastern bluebirds. One baby had a totally bald head after the attack. I haven't heard if they have seen it since it fledged. They moved the bluebird nest box about 100 yards further away from the trees and weren't certain that the adults would find the box, but before they were through re-erecting the box the parents were there scolding them and immediately resumed feeding as soon as the box was up. Miracles can happen.

Laura Erickson, Duluth, MN: I have done quite a bit of rehab for several years, and kept a Blue Jay as an education bird for 8 years. She molted all her head feathers simultaneously every year and was bald for a couple of weeks each time, looking awful. Meanwhile, a second Blue Jay I had to keep for several years molted his head feathers a few at a time, so he never looked awful. I never understood why Sneakers molted one way and BJ another.

Mort Cooper, Miami, FL: We here in South Florida are now into our annual fall molt. The Boat-tailed Grackles become tailless and our Blue Jays are entering their 'vulturine' stage where they lose every feather on their heads at the same time and fly around like diminutive blue vultures. It takes about 10 days for each individual to recover complete tail or head plumage.

Gail Petri, Fairport, NY: We have had a bald cardinal visiting our yard and he has been totally bald all summer. No sign of new growth -- but otherwise very healthy and active. I watched the same bird feast on a hatch of some sort of ant-like insect right next to our house. He stayed in the same spot for about 20 minutes, and after eating each insect, he twisted his head toward his tail and seemed to scratch his beak on his tail feathers. It was a very unusual behavior - and hard to describe in words. Have you ever heard of anything like that. What was it doing? Another mystery yet to solve.

Response: This is almost certainly behavior technically called anting. Birds obtain acid from insects and rub it into their feathers and skin in the process of grooming. Ants are most commonly used for, I believe, their formic acid (ants belonging to the family Formicidae). This may offer some additional support to the possibility of mites.

Two still more recent columns on this topic have appeared: Bill Hilton's and Ben Burtt's.