Date: 10/14/26 11:45 am From: Jared Del Rosso <jared.delrosso...> Subject: Re: [cobirds] Couch's Kingbird Feather Conditions - Arapahoe
Yes, same here. Thank you, Colin.
Will be interesting / revelatory to see if the bird persists here through
the cold and rain weather -- and the forecast frost on Friday morning.
- Jared Del Rosso
Centennial, CO
On Tuesday, October 13, 2026 at 7:33:29 PM UTC-6 Nathan Pieplow wrote:
> Thanks, Colin. This is precisely the analysis I hoped someone would
> provide!
>
> Nathan Pieplow
> Boulder
>
> On Tue, Oct 13, 2026 at 4:29 PM 'Colin Woolley' via Colorado Birds <
> <cob......> wrote:
>
>> This looks like what we'd call a second-year bird (hatched in 2025 and
>> now in its 2nd calendar year). Young kingbirds will often undergo an
>> eccentric pre-formative molt, meaning they replace outer primaries and
>> inner secondaries in their first fall. This is fairly unusual (but the norm
>> for kingbirds) as for most species, young birds won't replace any flight
>> feathers in their first fall. However, the eccentric molt pattern will
>> start somewhere in the middle of the primaries and proceed outward, while
>> also starting in the middle of the secondaries and proceed inwards, such
>> that juvenile flight feathers (inner primaries and outer secondaries) are
>> still retained through the first cycle. In this bird we see that the molt
>> started with p1 and is going outward, and has made it as far as p8, with
>> p9-p10 still retained but likely to drop soon. The secondaries have also
>> started to molt, beginning with s1. This is the standard pre-basic molt
>> pattern seen in adult birds, and not the eccentric pre-formative we'd see
>> in a young bird. The cool part here is, because the outer p9-10 are clearly
>> juvenile based on shape, we can say that this bird is undergoing its 2nd
>> pre-basic molt (i.e. starting its 2nd cycle). If the p9-10 had already
>> dropped and started growing in anew, we wouldn't be able to tell a
>> second-year from any bird that could be older. This also means that this
>> kingbird *didn't* molt outer primaries during its pre-formative
>> molt last fall, which according to the Pyle Guide is not as common but may
>> be seen more often in COKI in particular compared to other kingbirds. That
>> also explains why the p9-10 are so very worn out; they are juvenile
>> feathers and perhaps 16+ months old at this point and have more wear and
>> tear than any feather this bird will have the rest of its life. Here's a
>> diagram based on this photo <https://macaulaylibrary.org/asset/666411731> from
>> eBird.
>> [image: Screenshot 2026-10-13 143750.png]
>> Having so many photos of this individual bird in the Macauley Library is
>> great, and shows how valuable this resource is for studying molt. Keep
>> taking pictures of messy, molty birds!
>>
>> Colin Woolley
>> Wheat Ridge
>>
>> On Tuesday, October 13, 2026 at 2:02:04 PM UTC-6 Buzz Schaumberg wrote:
>>
>>> Thank you.
>>>
>>>
>>> Sent from the all new Aol app for iOS
>>> <https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661> >>> Buzz Schaumberg
>>>
>>> On Tuesday, October 13, 2026, 12:57 PM, Paul Malinowski <
>>> <pilla......> wrote:
>>>
>>> Interesting link, Nathan. Thank you. Here's a photo I got Friday showing
>>> the distinct orange crown patch on her.
>>>
>>> [image: COKI-261009-2.jpg]
>>>
>>> Paul Malinowski
>>> Littleton, CO
>>>
>>> On Mon, Oct 12, 2026 at 6:05 PM Nathan Pieplow <npie......>
>>> wrote:
>>>
>>> Hi all,
>>>
>>> I got a spread-wing photo of the Couch's Kingbird that shows not all the
>>> flight feathers are worn:
>>>
>>> https://macaulaylibrary.org/asset/666136706 >>>
>>> The outermost two primaries, P10 and P9, are very worn, but the next few
>>> are fresh. Comparing their shapes with those at
>>> https://www.birds.cornell.edu/crows/kingbirdsX.htm makes it clear that
>>> the Colorado Couch's must be a female. I suspect it is a juvenile female,
>>> based on molt pattern, primary shapes, and the bare patches in the
>>> underwing visible in Paul Malinowski's photo, but I am not great at ageing
>>> birds by molt, so I'd love to hear other opinions. Juveniles are not
>>> supposed to have the orange crown patch which many people (not me) reported
>>> seeing.
>>>
>>> Nathan Pieplow
>>> Boulder
>>>
>>> On Sat, Oct 10, 2026 at 8:45 AM David Suddjian <dsud......>
>>> wrote:
>>>
>>> Jared, This BIRD BOMBS episode I'm Molting!
>>> <https://www.youtube.com/watch?v=oZ-F3pYfJJA&t=3s> offers a good primer
>>> on feather molt in our birds.
>>>
>>> David
>>>
>>> On Sat, Oct 10, 2026 at 7:30 AM Paul Malinowski <pilla......>
>>> wrote:
>>>
>>> Jared, I noticed that too this afternoon. Look at the bare spots in this
>>> photo as well as the worn feathers.
>>>
>>> [image: COKI-261009-1.jpg]
>>>
>>> Paul Malinowski
>>> Littleton, CO
>>>
>>> On Fri, Oct 9, 2026 at 6:49 PM Jared Del Rosso <jared.d......>
>>> wrote:
>>>
>>> I enjoy reading *Birds of the World*, but I don't understand plumages,
>>> molts, and the terminology used to describe them. So it's hard for me to
>>> understand what the Couch's Kingbird currently at Marjorie Perry Nature
>>> Preserve in Arapahoe County *should* look like. But the bird, who I
>>> visited for the first time this afternoon, looks to be really worn to me.
>>> Could someone out there who both has access to *Birds of the World* and
>>> understands the terms of molting, offer some perspective on this?
>>>
>>> Here's a couple photos from this afternoon that show what I mean.
>>>
>>> [image: Screenshot 2026-10-09 at 6.46.43 PM.png]
>>>
>>> [image: Screenshot 2026-10-09 at 6.47.28 PM.png]
>>>
>>> - Jared Del Rosso
>>> Centennial, CO
>>>
>>> --
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To post to this group, send email to <cob......>
>>> For more options, visit this group at
>>> http://groups.google.com/group/cobirds >>> * All posts should be signed with the poster's full name and city.
>>> Include bird species and location in the subject line when appropriate.
>>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >>> ---
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to cobirds+<u......>
>>> To view this discussion visit
>>> https://groups.google.com/d/msgid/cobirds/<b79b99b0-217d-404f-a18d-02511b8d6a75n...> >>> <https://groups.google.com/d/msgid/cobirds/<b79b99b0-217d-404f-a18d-02511b8d6a75n...>?utm_medium=email&utm_source=footer> >>> .
>>>
>>> --
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To post to this group, send email to <cob......>
>>> For more options, visit this group at
>>> http://groups.google.com/group/cobirds >>> * All posts should be signed with the poster's full name and city.
>>> Include bird species and location in the subject line when appropriate.
>>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >>> ---
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to cobirds+<u......>
>>> To view this discussion visit
>>> https://groups.google.com/d/msgid/cobirds/CAMzYqKpqhPNXJ4fp-QXqPoAwuh9XXWO1ujra2wYnGJ%<2BWFMVd8g...> >>> <https://groups.google.com/d/msgid/cobirds/CAMzYqKpqhPNXJ4fp-QXqPoAwuh9XXWO1ujra2wYnGJ%<2BWFMVd8g...>?utm_medium=email&utm_source=footer> >>> .
>>>
>>> --
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To post to this group, send email to <cob......>
>>> For more options, visit this group at
>>> http://groups.google.com/group/cobirds >>> * All posts should be signed with the poster's full name and city.
>>> Include bird species and location in the subject line when appropriate.
>>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >>> ---
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to cobirds+<u......>
>>> To view this discussion visit
>>> https://groups.google.com/d/msgid/cobirds/CAGj6RoqZgexWO7y_sWWDiifyQ_g73OBJQMZJ%2BAOqqtH%<2BUTfCVA...> >>> <https://groups.google.com/d/msgid/cobirds/CAGj6RoqZgexWO7y_sWWDiifyQ_g73OBJQMZJ%2BAOqqtH%<2BUTfCVA...>?utm_medium=email&utm_source=footer> >>> .
>>>
>>> --
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To post to this group, send email to <cob......>
>>> For more options, visit this group at
>>> http://groups.google.com/group/cobirds >>> * All posts should be signed with the poster's full name and city.
>>> Include bird species and location in the subject line when appropriate.
>>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >>> ---
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to cobirds+<u......>
>>> To view this discussion visit
>>> https://groups.google.com/d/msgid/cobirds/CAFhaDVJndt%2Ba%2B9KbD6zBjV7opYRymW0_%3DoGSCX8GNvAG88%<2BPRQ...> >>> <https://groups.google.com/d/msgid/cobirds/CAFhaDVJndt%2Ba%2B9KbD6zBjV7opYRymW0_%3DoGSCX8GNvAG88%<2BPRQ...>?utm_medium=email&utm_source=footer> >>> .
>>>
>>> --
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To post to this group, send email to <cob......>
>>> For more options, visit this group at
>>> http://groups.google.com/group/cobirds >>> * All posts should be signed with the poster's full name and city.
>>> Include bird species and location in the subject line when appropriate.
>>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >>> ---
>>> You received this message because you are subscribed to the Google
>>> Groups "Colorado Birds" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to cobirds+<u......>
>>>
>>> To view this discussion visit
>>> https://groups.google.com/d/msgid/cobirds/<CAMzYqKr_O5rSA9aokMh5x45RqHq3XY-JAvKveH9tQntqRmOabQ...> >>> <https://groups.google.com/d/msgid/cobirds/<CAMzYqKr_O5rSA9aokMh5x45RqHq3XY-JAvKveH9tQntqRmOabQ...>?utm_medium=email&utm_source=footer> >>> .
>>>
>>> --
>> --
>> You received this message because you are subscribed to the Google Groups
>> "Colorado Birds" group.
>> To post to this group, send email to <cob......>
>> For more options, visit this group at
>> http://groups.google.com/group/cobirds >> * All posts should be signed with the poster's full name and city.
>> Include bird species and location in the subject line when appropriate.
>> * Join Colorado Field Ornithologists https://cobirds.org/membership/ >> ---
>> You received this message because you are subscribed to the Google Groups
>> "Colorado Birds" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to cobirds+<u......>
>>
> To view this discussion visit
>> https://groups.google.com/d/msgid/cobirds/<2c8afcff-53d2-402e-9680-0b378abb879an...> >> <https://groups.google.com/d/msgid/cobirds/<2c8afcff-53d2-402e-9680-0b378abb879an...>?utm_medium=email&utm_source=footer> >> .
>>
>
--
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To post to this group, send email to <cobirds...>
For more options, visit this group at
http://groups.google.com/group/cobirds * All posts should be signed with the poster's full name and city. Include bird species and location in the subject line when appropriate.
* Join Colorado Field Ornithologists https://cobirds.org/membership/ ---
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+<unsubscribe...>
To view this discussion visit https://groups.google.com/d/msgid/cobirds/<85b676b3-4e8d-492a-97c3-1840a071e161n...>
