Date: 12/30/24 8:37 am From: Erik Enbody <erik.enbody...> Subject: Re: [MBBIRDS] White Wagtail, Wilder Ranch SP
Hey Glen et al,
I’ve also been curious about the subspecies on this excellent find by Emma Arul on the CBC and have been looking through yours and others photos of the bird. The identification of first winter or adult winter female lugens (black backed) and ocularis is not always possible in the field and this individual seems to be along this gradient somewhere. However, if the bird is a first winter, which I think it likely is, the white greater coverts with dark centers (visible in the highest resolution photos) are more consistent with lugens, whereas ocularis tends to retain their juvenile coverts into the winter (which would appear as two white wing bars). The thicker and messier eye stripe behind the eye is also closer to lugens. In some angles of photos I’ve seen, it looks like a few dark centers on feathers on the back, but this isn’t always apparent and could be a photographic artifact.
I asked Per Alström, the author of the wagtail book, who agrees it is likely a lugens. However, he wasn’t sure it was identifiable from the photos available yet. If anyone can get a clear flight shot that shows the spread wing clearly, this would help get a little closer.
Best,
Erik
--
Erik Enbody
Postdoctoral Scholar
UC Santa Cruz / California Conservation Genomics Project
January 2025:
Susan E. Lynch Assistant Professor
Department of Computational Biology
Cornell University
erikenbody.github.io
> On Dec 30, 2024, at 1:09 AM, 'Glen Tepke' via mbbirds <mbbirds...> wrote:
>
> PS: I understand that this bird has been identified as ocularis, which is the most likely subspecies here, but I am curious about how the subspecies ID was determined. To my eye, the extensive white wing panel, thick black post-ocular line connecting to a prominent triangular post-ocular spot, and medium gray (not black) crown fit Sibley's illustration of 1st winter female lugens (Black-backed) just as well as any of the other plumages illustrated in Sibley or Nat Geo. Several photos are in this checklist:
>
> https://ebird.org/checklist/S207155378 >
> Glen Tepke
>
> On 12/29/2024 3:12 PM, 'Glen Tepke' via mbbirds wrote:
>> The White Wagtail on Wilder Beach continues today. Jake Gifford spotted it around 2:00 and we had it in view for about 10 minutes before it disappeared. It was fairly close to the overlook, roughly between a fifth and a quarter of the way down the beach, foraging around the driftwood logs and wrack.
>>
>> Glen Tepke
>> Santa Cruz
>>
>>
>
> --
> You received this message because you are subscribed to the Google Groups "mbbirds" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to mbbirds+<unsubscribe...>
> To view this discussion visit https://groups.google.com/d/msgid/mbbirds/<c08ad25c-9ce7-4681-a14e-0f1a4c1e1cfa...>
