Dowitchers in Bolinas Lagoon, California, January 2023 (1 Viewer)

[Eildert]

Hello,
I was wondering if anyone would be willing to help IDing these winter plumage Dowitchers? I thought perhaps the central bird could be Short-billed based on its hump-backed appearance and barred flanks but I would be very grateful for any input.

Thanks and happy New Year,

Eildert

 

[Butty]

Various other (posture-dependent) humps in that photo too... ☹️

 

[Eildert]

That's right, and I'm trying to find out what can be gleaned from these. I'm curious how reliable the two field marks (hump, barred flanks) are considered to be for winter dowitchers?

 

[tom baxter]

That's right, and I'm trying to find out what can be gleaned from these. I'm curious how reliable the two field marks (hump, barred flanks) are considered to be for winter dowitchers?

I doubt there is any way to be sure, but it does appear that the individual on the left of the frame in the foreground could be a Short-billed Dowitcher. The others appear to have larger bodies and more humped backs, which is an awful field mark to use, but they also appear to have long-ish tibias. This is also hard to assess, but is a characteristic of Long-billed. I think most of these, if not all are probably Long-billed. Only the one on the left gives me the impression of a possible Short-billed, but these are as tough as it gets. A good side profile with the head and entire bill would provide valuable clues. Additional things to try to note in the field include the tendency for Long-billed to call frequently while feeding, while Short-billed virtually never does, and the frequent tendency for Long-billed to wade into water that is touching their belly. Short-billed do this far less often and it is a strong indication to take into account in combination with other field marks of course.

To answer your more recent question, those have never been very helpful field marks for me. I find that the head shape is by far the most reliable field mark, but only when it’s a perfect side profile. The bill length and shape can also be very helpful sometimes, not always.

 

[Eildert]

Hi Tom,
That is very helpful information, thank you very much indeed!