Colombia Amazon - Flatbill (1 Viewer)

[TomFriedel]

This bird was seen in varzea forest in Leticia, Amazonas, Colombia.

Yellow-olive Flatbill | BirdPhotos.com

www.birdphotos.com

Offhand it looks like it could be a Grey-crowned Flatbill. It was seen near an active nest with this bird

Yellow-olive Flatbill | BirdPhotos.com

www.birdphotos.com

that has more white, but similar wing bars.

My understanding had been that the Zimmer's Flycatcher shows the least wingbars of the flatbills, and that the Pacific version, Yellow-margined Flatbill has no wingbars at all, just yellow edges to the wing feathers. That Zimmer's has slight wingbars is based on illustration in the ProAves field guide, and a photo of Zimmer's from someone I trust. And the Yellow-olive Flatbill looks more like this: Yellow-olive Flatbill | BirdPhotos.com

On the BOW Cornell page the Yellow-Olive Flatbill photo to me could not possibly be that species because it has no wingbars. Maybe this is a difference in an Amazon subspecies as I understand it, and I am guessing it is just citizen science at it's worst. The wingbars in these photos look to me like Zimmer's or Grey-crowned, but not Yellow-olive.

I always look for some black in the lower mandible of Grey-crowned, and don't see that here, making me think this could be Zimmer's.

The nest was woven underneath a palm leaf 3-4 meters above the ground. Most flatbill nests I have seen are hanging.

thanks, and I hope this post came out ok, there is virtually no Internet here.

 

[mjh73]

Don't suppose you recorded the call?

 

[mjh73]

I agree your choices are Zimmer's or Grey-crowned, and I'm tending towards Zimmer's. Call would nail it.

Ridgely says that compared with Grey-crowned "Zimmer's Flatbill is very similar but somewhat larger, dark-eyed, and has a mainly pale lower mandible; it's wing bars are more prominent and it shows a pale primary speculum (faint or lacking in Gray-crowned); voice differs dramatically.

Voice (Zimmer's): leisurely series of three or so whistled notes, each slightly higher pitched and shriller...... paraphrased as "one .... two.... three!"
Voice (Grey-crowned): song an inflected somewhat wheezy 'fiwee?' given at either intervals of 1-2 seconds or in a short series

 

[TomFriedel]

Thanks. They seemed busy gathering nesting material and were not vocalizing as far as I could tell.

 

[AveryBartels]

I would also lean towards Zimmer's, for the reasons outlined above. I find it interesting that neither bird shows the pale patch at the base of the primaries but for the most part, other features seem to add up for that taxon. In other ponderings, given that one shows it and one doesn't, I wonder if the white loral stripe is sex-related?

 

[TomFriedel]

I would also lean towards Zimmer's, for the reasons outlined above. I find it interesting that neither bird shows the pale patch at the base of the primaries but for the most part, other features seem to add up for that taxon. In other ponderings, given that one shows it and one doesn't, I wonder if the white loral stripe is sex-related?

On BOW they don't have information about Zimmer's nest, but Yellow-margined is "Nest a retort-like pear-shaped bag made of fine black fibres and fungal rhizomorphs". I can't find a definition for retort that makes sense here, but I don't see the word 'hanging', and the Grey-crowned is described as a hanging nest. This nest was woven below a palm leaf. So one more thing for Zimmer's maybe, but if it is Zimmer's it should be subspecies obscuriceps that should have an olive crown.

 

[TomFriedel]

Birds of Colombia - Tolmomyias

Birds of Colombia

birdsofcolombia.org

This photo is by a great photographer and someone I trust to have to correct ID, and is from Manaus.
I dont know if that is the same subspecies but it does have a more olive crown. By 'pale patch' you mean the upper wingbar, which is the base of primaries or primary coverts (I get confused by bird anatomy)? It does look different and more pale in this photo than my photo from Leticia. In BoW (from HBW that Cornell shut down) I don't see Zimmer's should have a pale less yellow upper wing bar, but the above photo seems to have it. The bird above is also much paler in front than my photo, so I am now leaning to Yellow-Olive subspecies peruvianus, which should be much yellower than Zimmer's.

I would also lean towards Zimmer's, for the reasons outlined above. I find it interesting that neither bird shows the pale patch at the base of the primaries but for the most part, other features seem to add up for that taxon. In other ponderings, given that one shows it and one doesn't, I wonder if the white loral stripe is sex-related?

 

[AveryBartels]

Birds of Colombia - Tolmomyias

Birds of Colombia

birdsofcolombia.org

This photo is by a great photographer and someone I trust to have to correct ID, and is from Manaus.
I dont know if that is the same subspecies but it does have a more olive crown. By 'pale patch' you mean the upper wingbar, which is the base of primaries or primary coverts (I get confused by bird anatomy)? It does look different and more pale in this photo than my photo from Leticia. In BoW (from HBW that Cornell shut down) I don't see Zimmer's should have a pale less yellow upper wing bar, but the above photo seems to have it. The bird above is also much paler in front than my photo, so I am now leaning to Yellow-Olive subspecies peruvianus, which should be much yellower than Zimmer's.

Hi Tom, the pale patch I'm referring to is what is often referred to as a "speculum" on songbirds. Where I mean is circled in the attached image. An example of a bird from Peru showing this is here: Yellow-margined Flycatcher Macaulay Library ML234866611

Apparently this is a feature that can be helpful separating Yellow-margined (speculum present) from Yellow-olive (absent). I'm not sure where Gray-crowned stand on this. However, given the complexity of this genus it may be that "Zimmer's" show this trait less than western/Central American populations.

 

[TomFriedel]

Hi Tom, the pale patch I'm referring to is what is often referred to as a "speculum" on songbirds. Where I mean is circled in the attached image. An example of a bird from Peru showing this is here: Yellow-margined Flycatcher Macaulay Library ML234866611

Apparently this is a feature that can be helpful separating Yellow-margined (speculum present) from Yellow-olive (absent). I'm not sure where Gray-crowned stand on this. However, given the complexity of this genus it may be that "Zimmer's" show this trait less than western/Central American populations.

Thanks for clarifying that. When the first poster mentioned it, I thought it might be something only visible to ornithologists with the bird in hand, or something often hidden by wing coverts. I wasn't sure that when you said pale patch you were talking about the same thing.
I read through the description for Zimmer's again and it should not have an all white lower mandible. Could it be that simple?

 

[Butty]

the pale patch I'm referring to is what is often referred to as a "speculum" on songbirds. Where I mean is circled in the attached image

Not often enough that I've ever heard of it - and, given that it's in a completely different place to the (very well-known) feature called a speculum in ducks, it's guaranteed to be confusing. So I hope that this usage never becomes any more widespread than it is(n't) at present.

 

[AveryBartels]

Not often enough that I've ever heard of it - and, given that it's in a completely different place to the (very well-known) feature called a speculum in ducks, it's guaranteed to be confusing. So I hope that this usage never becomes any more widespread than it is(n't) at present.

Yes, perhaps a blessing that it is not commonly used as you are quite right that it is in a completely different part of the wing than on waterfowl