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
>
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