Merriman-Webster defines acuity as "the quality or state of being able to sense slight impressions or differences".
What do you notice when you study this Pileated Woodpecker (PIWO)? Take a moment. Look closely. You might even make a short list of things that stand out about this bird.
I think we all realize there is a lot more happening around us than we can catch at first glance. This is one of the reasons digital photography is so useful. It gives us a second chance to observe and look more deeply for clues that may have eluded us initially.
In the photo above, you may have first noticed that the red forehead and red malar stripe indicate this is a male Pileated Woodpecker.
The eye color could easily be the next detail that catches your attention. The grey iris (with perhaps a slight hint of yellow) indicates this is a first-year bird, especially given it was a July 30th photo, so this first-year bird was only a few months old. Most, but not all, adults typically have yellow irises. Another even more subtle clue is the lack of discoloration on the white feathers closest to its bill. Adults often have yellowing in that area. I believe it comes from their feathers being stained by moist, decomposing wood as they excavate for carpenter ants and their larva.
At this point, this young bird has been mostly fed by its parents. It has not spent enough time excavating in decaying wood for its white feathers to become stained. You may have also noticed the sparseness of the red feathers on its head and the amount of downy white fluff on its shoulder. I suspect these clues are also more common among first-year birds.
This young one was also accompanied by an adult. When the adult leaned over and fed the young one, that was the most obvious clue to their parent-child relationship and the young one's age.
Seeing the unique pattern of feather coloring on the adult, I was virtually positive this was the same adult male I had seen feeding nearby less than a month earlier.
Normally, black feathers turn brown from the sun-bleaching the color and from normal wear and tear. Spotting a few faded brownish feathers on a Pileated Woodpecker was not surprising. However, this was the first Pileated Woodpecker that I remembered seeing, with such a variety of old brown feathers mixed in among the newer, darker feathers. I wondered if there might be more to the story than just old feathers.
I asked my birding friends if they had ever seen a Pileated with feathering quite like this. They all said, "No".
Later, I remembered seeing Goldie, a 2017 female feeding young at her nest in the Arboretum. I recalled that she looked really bedraggled.
Here is that 2017 photo. She does look wet. Plus, she does have some light brownish colored feathers, but nothing close to the mix on the male in the 2026 photo.
While looking for more information on the internet, I came across a wonderful article called "The Plumages of Pileated Woodpeckers" by Peter Pyle. Click Here to open "Bird Pop!", then scroll down to the beginning of the second paragraph to download "The Plumages of Pileated Woodpeckers" article. The amount of research and inspiration Peter did to ascertain this unique woodpecker molting process is a stunning example of acuity and intelligence.
If you are not a bird bander, you may not know about Peter and his larger, earlier publications. He is also the author of the two-volume "Identification Guide to North American Birds". These books are densely populated with efficiently coded descriptions, explicit diagrams, and abundant tables that describe North American birds, by age, gender, and molt in the greatest possible detail. These references help bird banders to identify and describe the birds they catch and band. Together, these books are commonly called "The Bander's Bible".
After reading The Plumages of Pileated Woodpeckers multiple times, but still not confident in my ability to see the correct feathers and understand the appropriate implications, I decided to send an email to Peter. I also included a lingering question I have about the eye colors of Pileated Woodpeckers. Here is that exchange:
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Mr. Pyle,
Two quick questions.
Item 1:
In my limited experience, the adult male PIWO in the next photo is in an exceptional state of molt. This adult male was accompanied by a FY male which he was occasionally feeding.
Your 2021 article on the Plumages of Pileated Woodpeckers is awesome. I am perhaps a bit slow to comprehend all the details. Does this degree of molt imply this bird is after fourth year?
I took the photo on Whidbey Island, in Washington State, on 7/30/26. Feel free to use the photo if you find it useful.
Item 2:
Ten years ago I noticed a minority of PNW PIWO photos showed females with "red" irises.
In Part 1 of your excellent "ID Guide to NA Birds", While referencing HY/SY in the penultimate paragragh of page 204, you state "...iris color probably grayer or browner (vs deep red in ASY/ATYs) through Jan."
[Editorial note: HY/SY means Hatch Year/Second Year and ASY/ATY means After Second Year/After Third Year.]
Birds of the World states,
"Iris
Brown in Juveniles and first-year females; brownish yellow in first-year males (B.L. Noel pers. comm.); yellow to golden in adult males and some adult females. Not known when iris in female changes to yellow,.."
Here is an old photo I took that shows the significant difference in iris color between a male and a female in virtually the same light.
(FYI - One of my readers did send in a photo of a one male with "red" eyes.)
My question is, Do you think red irises are a stage between the grey/brown of youth and the yellow of adulthood?
Given that this pair is mating, perhaps the yellow stage in females comes later in life, i.e. sometime after adulthood begins.
Thank you for any thoughts you have time to share.
Sincerely,
Larry Hubbell
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Peter Pyle's Response:
Hello Larry -
Thanks for the kind words about the article and ID Guide.
I have seen other examples of PIWOs with worn feathers like your first bird. In a quick look through Macaulay I found this one from Virginia.
I'm unsure if this is simply wear on feathers that did not get molted for 1-2 years of if there is also a pigment issue. Assuming the former (they do look quite worn in any case), it would depend on whether or not the older secondaries are juvenile or not. If juvenile I'd probably go with a 4th year bird having retained those feathers for two molts. But my hunch is that they are older (basic) feathers, as the retained back feathers and wing coverts look of the same age and I don't think they are juvenile. This would put age as at least 5 years old. Being able to see the primary coverts would help with the age question but they are covered by the greater coverts in the image. In any case it is in an anomalous state of molt as you surmised.
The iris question is a good one and I'm not sure of the source for my statement in the guide about it becoming redder in older birds. In a glance thorugh Macaulay
I also see a minority of adults of both sexes with reddish iris, examples:
females
males
But also many yellow and orange irises. My best guess is that they go from grayish to yellow to orange to red in both sexes, a similar pattern to what we see in Sharp-shinned and Cooper's Hawks. So your photo may show, e.g., a 3-year old male and an older female. Both birds are at least three years old based on the plumage that can be seen.
Hope this helps.
Peter
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My response:
Peter,
I really appreciate all of your detailed research, writing and guidance. This makes your taking time to reply and explain your thought processes to me incredibly valuable and enlightening. Thank You!
Item 1:
This photo was taken when the adult bird leaned over to feed the young one. I think I am seeing at least one brown primary covert above the small sliver of white showing through from the inner portion of a primary feather.
Item 2:
My best guess is that they go from grayish to yellow to orange to red in both sexes, a similar pattern to what we see in Sharp-shinned and Cooper's Hawks.
Either way I totally understand.
Thanks again!
Sincerely,
Larry Hubbell
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Peter's Response:
You are welcome.
The primary coverts do help in that the inner one visible is newer than the outer one. It is also in the area where the last coverts are replaced in molt sequence. So it's not being juvenile reinforces the age as 5 years or older.
Yes, feel free to repost any of the below.
Cheers, Peter
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My original post on the subject of red eyes in Pileated Woodpeckers was inspired by the disappearance of a red-eyed female, whom I called Storm. Click Here to read that post. During the post, I asked readers to send in their photos showing the eye colors of Pileated Woodpeckers. Ultimately, readers responded to my request and provided dozens of photos showing Pileated Woodpeckers and their eye colors. I concluded there were 24 unique adult Pileated Woodpeckers in the photos. I did not count obvious FY birds or obvious duplicate photographs of the same bird. This is not a scientifically controlled experiment. However this informal survey provided the following information:
Eye Color Female Male Total Percent
Yellow 16 4 20 83.3
Orange 2 0 2 8.3
Red 1 1 2 8.3
On its own, this information did not lead to a logical conclusion. However, it does seem to align with our observations and Peter's idea that adults initially develop yellow irises that then potentially turn orange and ultimately become red, if they survive long enough.
A special Thank You for your photographic contributions to:
- Gene Beall,
- Craig Kerns,
- Eric Kowalczyk,
- Gerald Lisi,
- Dennis Paulson,
- Christine Southwick,
- Trileigh Tucker,
- Leroy Vanhee,
- Milt Vine.
While revisiting the Storm Passing post I took a closer look at two of the photos.
This 2013 photos shows Storm with an orange iris.
Even though this photo is from the opposite side, I do believe it shows the same individual bird - note the thin supercilium and the fact that she was found in the same "territory" where she was photographed both before and after.
Now, meaning a year later in 2014, her orange irises have turned red. I accept that this is my belief (regarding the individual bird's identity) and so not scientific proof. However, if I am correct, her changing eye color supports Peter's color change concept.
Part of the challenge with scientifically proving this eye color change is that unlike feathers and skins, which can be stored and studied in museums, the eyes of birds decompose very rapidly. (Which is why the eyes in museum display specimens are typically manmade.)
The best scientific method(s) to validate and prove Peter's Theory, that I can think of, are:
A) Capturing banded birds multiple times during their lives and photographing their eyes as they change over time. This would most likely require an enormous amount of luck and effort.
B) Photographing a bird in captivity as it ages - perhaps an injured bird in an appropriate care facility that could not survive without assistance. By the way, there is such a bird, he is called Norman, in the John Ball Zoo in Grand Rapids, MI. I have sent an email asking for their help. This might be the best opportunity to solve this conundrum.
C) Someday, maybe AI will be able to identify individual birds, from all publicly available photographs, and essentially track individuals and their eye color change over time. When and if this capability becomes available it could provide both breadth and depth of proof. This would be especially useful if photos of the woodpeckers, while in their first few years, could be used to establish their age using the plumage assessment methods discovered by Peter Pyle.
(Thank you to Martin Tweedy for suggesting this idea in another context!)
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One last comparison of feather replacement.
While looking back at the post mentioned earlier, I also noticed this photo. The significant color difference between the newer, dark tail feathers and the weathered primaries, secondaries and coverts is startling. It is very interesting to compare this set of nearly uniformly colored brown flight feathers versus the mottled mix of brown and black feathers on the back and wings of 2026 adult male in the first photo I sent Peter.
It makes me wonder if their plumage replacement process continues to evolve as adult Pileated Woodpeckers grow older. The male still had yellow eyes, while Storm in the 2013 photo had orange colored irises. If Peter's theory is correct this should make her the older bird (at the time the photos were taken) and would imply that the male still has his iris color change to come. Plus, it makes me wonder if the molting sequence might continue to evolve and change with age.
There are many, many questions left to ask and answer. Some examples, Can we prove that the eye colors of males and females develop and change in the same sequence? If so, do the changes happen at the same or different ages for both genders? Does the availability of food impact when the eye color change occurs? Do the eyes all of the subspecies of Pileated Woodpeckers develop along the same color scheme? Let's keep our eyes pealed and see what we can learn together.
Have a great day on Union Bay...where nature lives in the city!
Larry
Going Native:
Each of us who breathes the air, drinks water, and eats food should be helping to protect our environment. Local efforts are most effective and sustainable. Native plants and trees encourage the largest diversity of lifeforms because of their long intertwined history with our local environment and the local native creatures. Even the microbes in the soil are native to each local landscape.
I hope we can inspire ourselves, our neighbors, and local businesses to respect native flora and support native wildlife at every opportunity. I have learned that our most logical approach to native trees and plants (in order of priority) should be to:
1) Learn and leave established native flora undisturbed.2) Remove invasive species and then wait to see if native plants begin to grow without assistance. (When native plants start on their own, then these plants or trees are likely the most appropriate flora for the habitat.)3) Scatter seeds from nearby native plants in a similar habitat.4) If you feel you must add a new plant, then select a native plant while considering how the plant fits with the specific habitat and understanding the plant's logical place in the normal succession of native plants.
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Keystone native plants are an important new idea. Douglas Tallamy, in the book "Nature's Best Hope, " explains that caterpillars supply more energy to birds, particularly young birds in their nests, than any other plant eater. He also mentions that 14% of our native plants, ie Keystone Plants, provide food for 90% of our caterpillars. This unique subset of native plants and trees enables critical moths, butterflies, and their caterpillars that provide food for the great majority of birds, especially when feeding their young.
Note: Flowering plants and trees, i.e. those pollinated by bees, are also included as Keystone Plants.
This video explains the native keystone plant concept in more detail:
https://www.youtube.com/watch?v=O5cXccWx030
The Top Keystone Genera in our ecoregion i.e. Plants and trees you might want in your yard:
Additional content available here:
https://wos.org/wos-wp/wp-content/uploads/2022/10/Native-Plant-Resources-10-7-22.pdf
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In this area, I typically display at least one photo with each post to challenge us to know our native lifeforms.
These 3-4 inch tall cones were found beneath a true fir tree near the spot on Whidbey Island where the initial photos of the Pileated Woodpeckers in this post were taken. In a forest known to contain only native trees.
Use this Oregon State University link to read about the six true fir species of the Pacific Northwest, however only four of the six are found in Washington state, and determine from which type of tree these cones fell.
Note: The Douglas Fir is eliminated from consideration because it is not a true fir species and also because its cones (and needles) are quite different.
Scroll down for the answer.
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The Answer:
Only one of the true fir species of the PNW grows between sea level and 1000'. The highest point on Whidbey Island is a bit over 500'. Hence these cones fell from a Grand Fir tree.
Typically, Grand Fir cones fall apart while still sitting upright in the tree. I suspect in this case I found cones that were cut down by a Douglas Squirrel. I felt lucky to spot the cones during the window of time between when the squirrel dropped them and when it descended to dismantled the cones for the seeds.
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The Email Challenge:
In response, I have set up my own email list. With each post, I will manually send out an announcement. If you would like to be added to my personal email list please send me an email requesting to be added. Something like:
Larry, Please add me to your personal email list.
My email address is:
LDHubbell@comcast.net
Thank you!
FYI: I have begun using gmail to publish my posts since it allows more email addresses in a single batch. However, it still takes multiple days to send out the notices of a new post. Thank you for your patience.
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The Comment Challenge:
Bottom Line:
If you write a long comment, please, copy it before hitting enter. Then, if the comment function fails to record your information, you can send the comment directly to me using email.
My email address is:
LDHubbell@comcast.net
Larry
