Date: 6/19/20 6:03 pm
From: Rusty Scalf <rscalf...>
Subject: [obol] Re: Blue-eyed Redheads and Incidence of Recessive Gene Expression in Pileated Woodpeckers
Something similiar in Acorn Woodpeckers. See:

https://thebirdersreport.com/wild-birds/portrait-of-the-juvenile-acorn-woodpecker

---
Rusty Scalf

On 2020-06-19 17:52, Gerald Meenaghan wrote:

> All,
>
> I think Sarah Sloan's explanation based on her experience with bushtits makes sense. That is, this is likely a short-lived developmental change in iris color rather than a genetic mutation. That would support my review of photos of pileated woodpeckers in the Macaulay Library. Only ~1% of PIWO photos depict a blue-irised individual. Add filters for "juvenile" and "immature," and it rises to 10-20%, with another large percent having some variation of dark or not-quite-yellow irises. This would represent the development from immature to adult bird, from dark to light yellow iris, with blue being somewhere in between.
>
> Thanks to Sarah Sloan, Noah Stryker and Martin Stervander for their messages supporting this. Martin adds, "I don't think there's any reason to believe that blueish eyes in birds would necessary reflect a recessive trait that is being expressed in a homozygote for that recessive allele!"
>
> It's interesting to note that, at least anecdotally, this is true of certain human populations as well. Human babies are known to undergo iris color change in their first year, with the color solidifying around age 1.
>
> Gerry Meenaghan
>
> Eugene, OR 97405
> 541-221-4307
>
>> On Jun 19, 2020, at 5:35 PM, Sarah Sloane <sloane...> wrote:
>
> Yes. That's my thought. Female bushtits go through that stage before finally getting the adult eye color at about 3 months.
>
> But pileateds aren't my area of expertise, so I could be wrong!
>
> &&&&&&&&&&&&&&&&&&&&&&&&&&&
>
> Dr Sarah A. Sloane
> Associate Professor
> Dept. of Biology
> Division of Natural Sciences
> University of Maine at Farmington
> Farmington, Maine 04938
>
> <sloane...>
> 207-778-7484 (office)
> 207-500-3733 (cell)
>
> https://bushtitsrule.blogspot.com
>
> &&&&&&&&&&&&&&&&&&&&&&&&&&&
>
> On Jun 19, 2020, at 5:33 PM, Gerald Meenaghan <meenaghang...> wrote:
>
> Sarah,
>
> Thank you for your response. I think this is it. It's a developmental stage rather than a mutation. What you're saying is that all PIWOs likely go through this, but it is a short period of time and this accounting for only a small percentage of the PIWO photos I sorted through, even of those marked "juvenile" or "immature." Rather than it being a certain portion of all birds who experience this, you're saying that it's likely all birds who have blue (or some other version of light) iris coloration on their way to the adult bright yellow? So, basically, I photographed this bird in its very short-lived "blue iris" phase, and that next month (or a bit later) its eye color might be yellow? Is that closer to the mark?
>
> Gerry Meenaghan
> 2934 Mill St.
> Eugene, OR 97405
> 541-221-4307
>
> On Jun 19, 2020, at 5:26 PM, Sarah Sloane <sloane...> wrote:
>
> Are you sure the blue-eyed pileated isn't a juvenile of the year? Female bushtits hatch with dark brown eyes and the iris changes to cream or yellow very slowly. It passes through a gray-blue stage that looks very much like the iris in the picture.
>
> Just a thought.
>
> Sarah
>
> &&&&&&&&&&&&&&&&&&&&&&&&&&&
>
> Dr Sarah A. Sloane
> Associate Professor
> Dept. of Biology
> Division of Natural Sciences
> University of Maine at Farmington
> Farmington, Maine 04938
>
> <sloane...>
> 207-778-7484 (office)
> 207-500-3733 (cell)
>
> https://bushtitsrule.blogspot.com [1]
>
> &&&&&&&&&&&&&&&&&&&&&&&&&&&
>
> On Jun 19, 2020, at 2:35 PM, Gerald Meenaghan (Redacted sender "meenaghang" for DMARC) <dmarc-noreply...> wrote:
>
> Oregon / Lane Birders,
>
> This morning, John Sullivan and I had a really nice experience with a pair of pileated woodpeckers at Wayne Morse Ranch in Eugene. Upon my return home, I processed my pictures to find that the male (redhead) has blue irises. At first, I just thought it was cool-looking, but after a cursory Google image search, I'm finding it's quite rare. Another cursory search on eBird's Macaulay Library indicates that it's perhaps ~1/100, making it about as common as red hair in humans. Yellow irises are the norm, with dark (orange, brown) irises being the next most common. Does anyone have any leads on the prevalence of this blue iris recessive gene expression in pileated woodpeckers? Basically, how rare exactly are blue irises on a pileated woodpecker?
>
> I've attached one small example picture here. More can be found here: https://ebird.org/checklist/S70601778
>
> With thanks in advance,
>
> Gerry Meenaghan
>
> <meenaghang...>
> 541-221-4307 <Blue-eyed redhead7.jpg>


Links:
------
[1] https://bushtitsrule.blogspot.com/
 
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