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Confirm White shielded coot


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2 minutes ago, Tanager 101 said:

It definitely has the red on the forehead. To me it looks like enough red to be classified as a red-shielded one. I am no expert though.

The link I posted above is from the same location. It got confirmed as white shielded. Why does it have a hint of a red shield?

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Just now, IKLland said:

The link I posted above is from the same location. It got confirmed as white shielded. Why does it have a hint of a red shield?

hmmm I see what your saying. Maybe white-shielded is right.... I will point out that yours does have a bit more red then the other

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3 minutes ago, Tanager 101 said:

hmmm I see what your saying. Maybe white-shielded is right.... I will point out that yours does have a bit more red then the other

I'm NOT trying to force this ID, but that could be because of the angle of the head. Unfortunately, this was the only angle I got. 

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From BoTW:

In rare cases in the North American population, callus may be completely white or slightly yellowish (Payne and Master 1983, Roberson and Baptista 1988; see Systematics), although the white callus increases in frequency in the Greater Antilles, and predominates from Puerto Rico south to Venezuela (Raffaele et al. 1998). Base of culmen tinged with greenish yellow, inside of mouth and tongue white.

To me it seems like if there is any red, it’s a Red-shielded. Additionally, age may be a factor in the intensity and shade of the red callus (shield)

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1 minute ago, Avery said:

From BoTW:

In rare cases in the North American population, callus may be completely white or slightly yellowish (Payne and Master 1983, Roberson and Baptista 1988; see Systematics), although the white callus increases in frequency in the Greater Antilles, and predominates from Puerto Rico south to Venezuela (Raffaele et al. 1998). Base of culmen tinged with greenish yellow, inside of mouth and tongue white.

To me it seems like if there is any red, it’s a Red-shielded. Additionally, age may be a factor in the intensity and shade of the red callus (shield)

Okay so it looks like Red-shielded then

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1 minute ago, Avery said:

To me it seems like if there is any red, it’s a Red-shielded. Additionally, age may be a factor in the intensity and shade of the red callus (shield)

Then why do you think the person who saw a white shielded at that location earlier this year had some red on it? And it got confirmed. 

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1 minute ago, IKLland said:

Then why do you think the person who saw a white shielded at that location earlier this year had some red on it? And it got confirmed. 

Not sure about that. Reviewers can be wrong *runs into hiding*
 

Also, I have zero experience with white-shielded birds, so just wanted to give another perspective. I’ll look more in depth when I get back to my dorm in a few minutes

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Take everything I say here with a grain of salt, as I have zero experience with the "White-shielded" morph

Dug more into eBird photos and BoTW. Personally, especially without a full frontal view of the shield, and the fact that the overexposure may be affecting the colors, I wouldn't call this a "White-shielded" bird. It seems that since these two variants are morphs and not subspecies, there is likely to be greater variation, meaning some birds may not be able to be confidently identified.

BoTW described the "White-shielded" morph as having a completely white callus, or a yellow tinged shield. In the photos in Macauley, in all the photos with a good view of the callus, there is always the tiniest hint of red, like in the photo that got confirmed. Also, many of the birds have an obvious yellowish wash on the shield.

There are also a lot of photos with even more extensive red than I have seen in Red-shielded birds, but I'm guessing as those photos don't have comments regarding the morph decision, that they were just clicked on since they weren't "rare". Additionally, all these photos come from outside the U.S.

 

 

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"White-shielded" Coots are within the range of possibility in CA. Many birds can show a variety of intermediate traits with regards to the shield/callus. That being said, I'm afraid that in your photo, the whites are just too overexposed to make an accurate call. My sense is the same as others on this thread, and that this bird is not a candidate for the "White-shielded" designation in eBird, at least without clearer pictures.

However, good for you to keep an eye out on some of these subtle features that many observers overlook.  Keep it up.

The article written in 1988 by the person (Don Roberson) who identified and photographed the "White-shielded" bird you referenced.

https://sora.unm.edu/sites/default/files/journals/nab/v042n05/p01241-p01246.pdf

 

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