: Bald headed cardinals and blue jays in late summer. How does this happen?






BIRD COLUMN FOR February 22, 2004
By Benjamin P. Burtt

Here is a question from J.B. of Atlanta, Georgia who reads my column on line. In 1974 he was in my Chemistry class at Syracuse University and now teaches science in a private school in Atlanta.

He asked: I have seen several cardinals that had no feathers on their heads, one several years ago and one this year. Can you tell me something about this condition?

Dear J.B.:----Bald cardinals and jays are reported nearly every year in the late summer. Without feathers on the head, the bird resembles a tiny vulture. At the time, the feathers on the rest of the body are usually dull and worn looking.

Those of us who write on birds for newspapers or magazines receive questions about bald birds from time to time. I would guess that someone asks me about this almost every year. As far as I can determine, this matter has not been studied carefully. However, your question did prompt me to see if I could learn more about it.

There are several things that we do know.



1. It is observed most often with blue jays and cardinals.
2. When we can recognize adults and young, it is the adults that
show this condition.
3. Such birds are usually spotted in the summer.
4. Only a small percentage of each species shows this condition.

On the basis of the information summarized below, I have concluded that in most cases it is related to the way certain individual birds molt their head feathers. For those particular birds it is their normal process, but it differs from the way most individuals of their species undergo the molt.

The molting process

To understand the bald headed bird phenomenon we must learn something about feathers and the molting process.

Once a feather has grown to full size, it is no longer connected to the blood supply. So it gradually wears out. If it is broken of frayed, it cannot be repaired. So each bird must get a new set of feathers every year.

This takes place in late summer after the breeding is over. Adult birds lose all their feathers gradually and new ones grow in before fall.

If a feather is accidentally pulled out, a new one will grow right away even though it is not the molting season.

Birds born in the spring also molt in the late summer, but they replace only their body and head feathers. Those on the wing and tail are not replaced until the following summer.

For the blue jay and cardinal and for most songbirds, the wing feathers are lost one at a time from each wing. New feathers replace them before other wing feathers drop out. Thus the bird maintains its ability to fly. The tail feathers are lost slowly, a few at a time. This ensures that the tail will be able carry out its functions while the bird is flying.

However, on the body, many of the feathers can be lost simultaneously so there were will be patches where the feathers are scarce. The bird looks ragged and unkempt when both new and old feathers are present. Usually, the feather cover is thin, but seldom is a large patch of bare skin visible.

Among the blue jays, cardinals and grackles there are occasional individuals that shed most of their head feathers all at once. The blue jay in this sketch shows how such a bird would appear.

Within a week, much of the bare skin will be covered and in two weeks the head will be covered with feathers again.

The molting of the feathers all over the body and wings for the blue jay lasts about six weeks, starting in July. For most jays, the body and head feathers are lost from scattered locations here and there. During this process the skin is covered, but the coating is not very thick.

During July through August, the growing of all those feathers is a physiological drain on the bird. It needs more food to grow the feathers and to compensate for the heat lost due to the decreased insulation.

At this time the bird usually is less active. Singing and fighting stop. The bird skulks and hides. We may not see much of it as it conserves energy during this period while the feathers are being replaced.

All birds have this late summer molt. Many species have a second molt when they grow new feathers in the spring before they breed. Often this results in brilliant, new colors.

Sometimes the plumage changes in the spring are brought about by wear and not by molting. For example, the black-bib of the male house sparrow develops by spring. It is produced as the tan tips of the black feathers wear away. This exposes the black part of the feathers. So the new plumage and new appearance is produced without new feathers being formed.

The blue jay has only one molt in late summer. So it looks pretty much the same throughout the year. In the spring, its feathers are worn and faded. The blue is not so brilliant and black bars are less apparent in the spring than in the fall when its feathers are new.

The summer molt for birds occurs at a time that interferes the least with activities that require a lot of flying. So it comes when breeding is over and before the fall migration.

Most birds that capture flying insects need to do a lot of flying to stock up on food before they migrate south. So they postpone their molting until they are on their wintering ground. These include most flycatchers, swifts and swallows.

The purple martin, unlike the other swallows, starts molting before migration. During its long over water flights, the molting however is suspended and then is completed after the birds arrive in South America.

Waterfowl have a different molting process.

Waterfowl lose all their wing feathers at the same time and so have a period of time when they are temporarily flightless. This does not put them in danger, because their food and shelter are in the water and the marsh where they stay during this time.

NOW BACK TO THE BALD BIRDS

A bird that loses all the feathers on its head simultaneously is the exception, and such a bird is very conspicuous, but not very often seen.

Suggestions have been made that this could be due to a problem with the diet or an infestation of mites or caused by a disease. Another idea is that it is just the way that particular bird molts. It drops all the feathers on its head at one time instead of losing them gradually as do most birds of the same species.

I now believe that there indeed are differences in the way birds lose their head feathers when undergoing the late summer molt. While most cardinals, for example, lose their head feathers gradually, a few individuals lose all the head feathers simultaneously. There is no external cause, it is just the way that particular bird molts.

To make certain of this, we really need to follow the life of one of these individual birds for several years and observe the late summer molt each year. If it is due to mites or disease or a faulty diet, it is unlikely that a bald head will be observed every year at the time of the summer molt. On the other hand, if we find that this bird loses all its head feathers simultaneously in the same way every year in the summer, then it is clear that this is the way that particular individual molts. SUCH A BIRD HAS NOW COME TO MY ATTENTION!

It was reported by Laura Erickson of Duluth, Minnesota in response to a question asked by Gerry Rising of Buffalo, NY.. He writes a bird column for the Buffalo News and a reader had asked him about a bald cardinal in 1998. He used the internet and put the question to BIRDCHAT where his question was presented to some 1300 ornithologists around the world.

Among the many responses was the one from Laura Erickson. She is an educator and was a licensed wildlife rehabilitator.

She had two blue jays in captivity for a time that could not be released to forage on their own. She used them in lectures to school children and to adults and had a permit to keep them in captivity for educational purposes.

She observed their annual molting year after year. One lost its head feathers gradually every year as do most birds. However, the other blue jay in the same cage, molted all its head feathers simultaneously every year for eight years. It was bald for a couple weeks each time until its new feathers grew in.

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. So here we have the perfect experiment. 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.

Here is another useful piece of evidence. Bill Hilton Jr. is the Director of the Hilton Pond Center for Piedmont Natural History in York, South Carolina. He does a lot of bird study through banding. On July 30, 2001 he captured and banded a cardinal that had recently fledged. It apparently, hung around the Nature Center and was recaptured twice in 2002 as an adult female. It was not captured during the summer molting period.

She was captured three times in 2003. In May she had normal head plumage. In July, when captured she was bald and is shown in the picture just below on the left. A close-up from that same photograph is shown on the right. You can see a single red feather sticking up from the crown. This is probably one of the feathers that are part of the tuft.

Courtesy of Bill Hilton Jr.

In October she was again captured, but with a normal appearance. All the feathers had grown back.

Hiltons cardinal observations are consistent with the hypothesis that the bird was just molting, but they do not exclude the possibility of a one time disease or infestation with mites. I hope that he can capture that bird next year during the summer molt to see if it is bald then. If it is , then I think we can rule out disease or mites in the case of this particular bird.

In the light of Laura Erickson’s and Bill Hilton’s observations, I suggest that a small percentage of cardinals and a small percentage of blue jays do normally drop all of their head feathers simultaneously during the late summer molting process. For those particular birds, this is a normal occurrence and occurs in the same way every year and the bird immediately grows a new set..

Another cardinal may simultaneously drop only the feathers on the top of the head. The feathers on the nape and the side of the head may drop gradually. Presumably, it would molt that way each year.

There are two reasons that bald birds are seldom observed. Individuals with this molting pattern are rare, perhaps one out of a hundred cardinals ( a guess) and the bird is only completely bald for such a short time that the chances of seeing it when it is bald are very small. For example, in the case of the cardinal at Hilton Pond, that was banded in 2001, it was positively identified by capturing it and reading the band six more times. Only one of those times was during the summer molt and that was the only time its head was bald.

I hope that the bird can be captured next year during the summer molt to see if it is bald then. If it is, think we can rule out disease or mites in the case of this particular bird.


Above is a side view of a bald cardinal, courtesy of Marguerite McGinnis of Buffalo, NY who snapped the photograph in Batavia, Illinois. There are no feathers on the head at all. This picture was also used by Gerry Rising in his column in the Buffalo News in 1998.


Courtesy of Ramona M. Lauda

This bald male cardinal was photographed at Falls Church, VA by Ramona M. Lauda in the late summer of 2002. She sent the photograph with a question about the bird to the Cornell Laboratory of Ornithology. It was through Cornell that I was able to obtain the image and get permission from MS. Lauda to use it here.

Further information and pertinent images may be found on the websites listed below.

Reports of bald headed birds and some photographs were sent to the people running the Feeder Watch program at Cornell. You can read an article and see some of these photographs about those birds by visiting:

http://www.birds.cornell.edu/pfw/AboutBirdsandFeeding/BaldBirds.htm

If you wish to see a larger, sharp close up of the head of the Hilton pond cardinal and read Bill Hilton’s article about his cardinal, click on this underlined address.
http://www.hiltonpond.org/ThisWeek030701.html

You can read Gerry Rising's 1998 article on the bald cardinal by visiting http://www.acsu.buffalo.edu/~insrisg/nature/nw98/baldbirds.html

I suggest that you also visit the web site of the Hilton Pond Center for Piedmont Natural History at http://www.hiltonpond.org/ It has a lot of interesting and instructive information about many aspects of nature.

Laura Erickson has a web site well worth visiting at
http://www.lauraerickson.com/



January Feeder Survey Results and abundant Redpolls

BIRD COLUMN For February 8, 2004
By Ben Burtt

What birds were most abundant at feeders during the first week of January when we conducted the feeder survey? While geese and crows were more abundant than any other species reported, they were not at feeders.

The most abundant bird right at feeders was the goldfinch. There were 1,147 per 100 feeders. We always present the numbers per 100 feeders so that comparisons can be made with results in the past.

The count this year is higher than in any January since 1979. In mid winter the goldfinch has been more abundant than any other species in recent years.

After the goldfinch came the common redpoll with 974. It was followed by mourning dove, starling, junco and house sparrow. Then came the chickadee and house finch.

It is also fun to know what species are present at most feeders. As usual, just about everyone had chickadees. 97% of the feeders had at least one chickadee. Other birds that were common at feeders were juncos 91%, downy woodpeckers and goldfinches at 88% of the feeders. Mourning doves came in at 86%.

After that, 79% of the people reported crows and cardinals. Blue jays were not as common this time with only 73% of the feeders reporting them. Red-breasted nuthatches were seen at 72% and this is much higher than last year.

Other common species were house finch 60%, tree sparrow 55% and redpoll 52%.
That 52% is high for common redpoll. In December only one person reported it and he saw only one. There were none listed in November and October.

In January, these little finches visited feeders in flocks of about 20 birds and we had a total of 983 of them. They breed far to the north beyond the large trees and inhabit areas with brushy terrain. Every other winter they move south to visit us and this is one of those years.

CAPTION: The common redpoll from the far north showed up in large numbers for the first time this season on the January Feeder Survey. It is a chickadee sized bird and both male and female have a bright red forehead and a black chin. The male has pink on the breast. This painting is from the "Peterson Field Guide to Birds of Eastern and Central North America", fifth edition. (Courtesy of the Houghton Mifflin Co. )


Sharon Crain had 68 in Smyrna, Matt Young had a flock of 61 in his yard in the highlands east of Deruyter. There were 60 at Dorothy Crumbs feeder in Jamesville. Both Paul Radway in Pompey and Bill Purcell in Hastings listed 55.

If you did not have redpolls and wish to attract them, use black oil sunflower seed and be sure to have a tubular feeder with only niger seed in it. Redpolls are in the finch family and all such birds are strongly attracted to niger seed.

Now and then amongst the common redpolls we will see a few that have a lot of white on them. These are hoary redpolls and are shown in the field guides. They also live far to the north. Paul Radway and Matt Young each reported one hoary redpoll.

There are some redpolls whose plumage is between the extremes of these two species and it is sometimes very difficult to tell which one you are observing. Some scientists believe that they are just variations of the same species.

Goldfinches continue to be abundant and there were a few more siskins reported than in December.

A total of sixty species was spotted. Of these, 49 were fairly common, that is they were seen by 3 or more observers.

The other 11 species were seen by only one or two people. The typical feeder had 14 species. By that I mean that half of the observers had more than 14 and the other half had less than 14.

The shortest lists.

The shortest list came from the New Haven Elementary School class taught by Norma Griffin, they had three species. Ken Sparks of Cazenovia had 6. Tallying 8 species were Milt and Kay Bieber of Tully, Susan Cummins of McGraw and George and Jackie Miller of Potsdam.

In Mexico, Thelma Castle listed 9 and so did Eugenia Fish of Cortland. Listing 10 species were Elaine Lyon of Cortland and Judith Miller of Pulaski.

The longest list came from Waterloo, had 30 species and was turned in by Linda Quackenbush. Tallying 23 were Lawrence Abrahamson of Marcelluls, Steve and Dorothy Hanzlik of Whitney Point and Steve Swensen of Baldwinsville.

Winter Birds
Birds here in winter fall into three categories. First, those that live here throughout the year.

Secondly, are those that come down from the north for the winter such as the tree sparrow and the white-throated sparrow.

Thirdly, are those that remain here for the winter even though most of their tribe have gone south. Examples are robins and bluebirds.

Small numbers of robins are listed on every feeder survey through the winter. Normally, about 10 people have robins. This time, only the William Burch's at Skaneateles saw robins and they had five. Three people had a total of 6 bluebirds. Also very scarce were red-winged blackbirds, grackles and cowbirds.

Finches from the north

This year there has been no large movement of northern finches from Canada into our area except the redpoll. Only three people listed evening grosbeaks. Seven listed the pine siskin and there were no crossbills.

The report from the farthest north came from Peter and Linda Biesemeyer of Malone. In addition to more common birds, they listed some norther species, 2 ravens, a red-breasted nuthatch, three golden crowned kinglets, 15 redpolls, 3 siskins and 25 evening grosbeaks.

The Rare Birds

Steve and Dorothy Hanzlik of Whitny Point had a goshawk. Clifford Manchester of Ithaca saw snow buntings. At Brewerton, Sharon Sheedy had a sapsucker as did Ed Street of Cazenovia who saw one at his suet feeder on the day after the survey ended.

Kathy and Scott Trefz of Perryville were the only people to list a horned owl. These owls carry on their courtship in January, are the first birds to nest and will soon be incubating eggs.

In Manlius, Ilse Vogelpoel saw a fox sparrow. Ted Williams of Fabius listed a rusty blackbird. A chipping sparrow was listed by A.J. Wood of Oneida.

The total picture

Here is the list of all species reported. The first figure is the number of birds spotted per 100 reports and the one in parentheses is the number of reports out of 100 that listed the species.

If you divide the number of birds by the number of reports for a particular species you get the average number visiting a feeder. It is fun to compare this with your own tally for that species.

Canada goose 1,658 (32).

Ducks: black 2 (1); mallard 22 (3); bufflehead 20 (1);

Daytime birds of prey: northern harrier 2 (2); sharp-shinned hawk 8 (8); Cooper's hawk 9 (9); goshawk 1 (1); redtail 26 (18); roughlegged hawk 2 (2); kestrel 2 (2); pheasant 5 (2); turkey 123 (7).

Gulls: ring-billed 25 (6); herring 127 (4); rock dove 157 (17); mourning dove 784 (86); horned owl 2 (1).

Woodpeckers: red-bellied 55 (44); yellow-bellied sapsucker 1 (1); downy 196 (88); hairy 77 (49); flicker 9 (6); pileated 2 (2); blue jay 287 (73); crow 1,194 (79); raven 6 (2); chickadee 499 (97); titmouse 95 (48); red-breasted nuthatch 70 (44); white-breasted nuthatch 125 (72); brown creeper 6 (5); Carolina wren 3 (3); golden-crowned kinglet 3 (1); bluebird 6 (3); robin 5 (1); mockingbird 3 (2); cedar waxwing 126 (5); starling 673 (48); cardinal 290 (79).

Sparrows: tree 275 (55); chipping 1 (1); fox 1 (1); song 16 (7); white-throated 97 (25); white-crowned 2 (2); junco 571 (91); snow bunting 3 (1); red-winged blackbird 5 (3); rusty blackbird 2 (1); grackle 4 (2); cowbird 28 (2); purple finch 16 (7); house finch 428 (60); redpoll 983 (52); hoary redpoll 2 (2); pine siskin 38 (7); goldfinch 1,147 (88); evening grosbeak 35 (3); house sparrow 563 (44).