Bush Warbler ID Help, China (1 Viewer)

[xuky.summer]

I recorded this warbler today at Qingdao, shandong province. It looks tiny and has a same alarm call with Brownish-flanked Bush Warbler( also like call of dusky wabler). but the wing formula more in line with Manchurian Bush Warbler(such as p3 = p6/7–7/8). Is it a very little female Manchurian Bush Warbler or a Brownish-flanked Bush Warbler? the latter is uncommon at my location.

Thank you very much!

 

[Andy Adcock]

Which Bush Warblers, show a blue cast?

Edit: Answering my own question, Abberent?

 

[andyb39]

i don't have much experience with Bush Warblers. According to both the eBird and Avibase checklists for Shandong province, Manchurian is the only Horornis to occur there, apart from Japanese (a vagrant). The trouble is this bird doesn't look much like one - it's not rich brown and the supercilium is weak (Manchurian has a bold one, especially after the eye). Brownish-flanked looks a little more plausible. This is without gettng into wing formulae, etc.

 

[xuky.summer]

Thank you.
Brownish-flanked Bush Warbler is a rare breeder in Shandong province. Generally, it has a very thin and long bill, but the bill of this one looks a bit blunt.
I heard its sound many times, very similar to the dusky warbler, which is the alarm call in this link.
https://www.xeno-canto.org/explore?query=Horornis fortipes XC412636
Manchurian Bush Warbler is very common with me, but I have never heard it make a similar sound.

 

[Grahame Walbridge]

Thank you.
Brownish-flanked Bush Warbler is a rare breeder in Shandong province. Generally, it has a very thin and long bill, but the bill of this one looks a bit blunt.
I heard its sound many times, very similar to the dusky warbler, which is the alarm call in this link.
https://www.xeno-canto.org/explore?query=Horornis fortipes XC412636
Manchurian Bush Warbler is very common with me, but I have never heard it make a similar sound.

Xuky, you alluded to wing formula favouring Manchurian in your OP and I concur. WF details can be difficult to assess from images but my take is WP=p4, p2=p8/9 (or p9), p3=p6/7 which, should exclude Brownish-flanked, it having a more rounded wing e.g WP=p5-6; p9 falls nearer p9. Further, the pp looks too long + bill to heavy and blunt-tipped for BFBW. Presumably a female as you suggest.

Manchurian is presumably the default in your area but you might also consider the (much) rarer and very similar Japanese BW (ssp.cantans) which may be overlooked. It utters a call similar to Dusky (perhaps a little 'thicker') https://www.xeno-canto.org/332824 and, though I could not a find match for Manchurian on xeno-canto, Kennerley & Pearson state that it's repertoire does include a similar 'chak' call to that of Japanese.

A shame you were not able got obtain a recording.

Really out my depth here so hoping John Allcock will pick up on this thread and add something more constructive.

Grahame

 

[MacNara]

Manchurian is presumably the default in your area but you might also consider the (much) rarer and very similar Japanese BW (ssp.cantans) which may be overlooked. It utters a call similar to Dusky (perhaps a little 'thicker') https://www.xeno-canto.org/332824 and, though I could not a find match for Manchurian on xeno-canto, Kennerley & Pearson state that it's repertoire does include a similar 'chak' call to that of Japanese.

Details of wing formula are well above my pay grade, but I think the suggestion of Japanese Bush Warbler is unlikely (unless the continental bird is quite different from the bird in Japan).

Japanese Bush Warbler is extremely common where I live in Nara, Japan. Every photo I have shows an eyebrow that is as wide above the eye as it is in front of and behind the eye (as you can see in the attached photo). Xuky's bird has a weaker eyebrow overall which disappears over the eye. Also, the bill of Xuky's bird appears to be slightly downcurved which is not quite right for JBW. And in JBW, the lower mandible is usually yellowish. Indeed from looking at Brazil, 'Birds of East Asia' shouldn't Manchurian be basically the same?

A shame you were not able got obtain a recording.

Turning to the recordings: the xeno-canto link that Grahame gives for JBW is accurate. The winter sound as the bird moves around is like the sound that British speakers write as tsk tsk, or tut tut - a sound of disapproval. Sometimes it is repeated in a sequence, but often it's just given once, and then again maybe ten seconds or more later. But the link that Xuky gives sounds nothing like this to my ear, and I find it difficult to think that Xuky would have heard JBW and chosen this sound as a near-equivalent.

Really out my depth here so hoping John Allcock will pick up on this thread and add something more constructive.

Me too.

As Andy Adcock said above, the blue on the shoulder, wings, chest and tail doesn't seem to be a photo artefact, so are we even sure it's a bush (or other) warbler?

 

[johnallcock]

Really out my depth here so hoping John Allcock will pick up on this thread and add something more constructive.

Thanks Grahame. I actually started posting something yesterday, but got a bit confused and wanted to come back today for a fresh look. It's an intriguing bird. I should point out that I have no experience of Japanese, so I'm going on comparison of Brownish-flanked and Manchurian, as these are the more likely species at the location.

My immediate instinct on this bird is that it's not a Manchurian - as Andy mentioned above, the supercilium is quite weak and it does not have much rufous tone. Overall I thought it looked more like a Brownish-flanked, apart from the confusing wing formula.

In terms of call, I have occasionally heard variation from both BfBW and MBW, which can be very confusing. When I've heard this, it's usually been a single-note call, rather than the usual rattle (MBW) or double-click (BfBW). Male and female birds also seem to have subtly different calls, which can be confusing if you are more familiar with one.


So that was my opinion yesterday, but looking a bit more closely now I think I might change my opinion from that first impression. There is quite an obvious dark eyestripe, especially on the first image, which I would expect on MBW but not BfBW. The posture, with slightly drooping wings and slightly cocked tail, looks wrong for BfBW, more like I would expect for MBW.

And looking carefully at the photo this evening, I think that the forecrown is slightly more rufous than the rest of the crown, with a similar pattern to MBW, although this is less obvious than expected. I think this may be a bit less obvious on the photos due to the light conditions. xuky, I hope you don't mind that I've tried adjusting the colour tones on a couple of your photos to see how that affects my perception. Suddenly the bird looks a lot more like a Manchurian to me, not only the crown pattern but also the upperpart tone.

So, on balance, I think that this is probably a dull Manchurian BW, probably female based on the apparent size. I'm not 100% sure though, so if anyone has further comment I'd be interested to hear.

 

[xuky.summer]

Hi Grahame, Thank you for finding this sound. It seems to me that this sound is closer to what I heard. I have not found a similar sound under the Manchurian on xeno-canto.org, and I also have never heard a similar sound from them, plus it is very small ( only the size of Dusky warbler), so I suspect it is a Brownish-flanked. If the JBW can make a similar sound, then I believe the Manchurian will also do. It is strange that the Manchurian is very common here, but I have not heard of it.
Hi MacNara, thank you for your analysis. I also think it is not JBW. For example, there is some reddish brown on the head, and the flanks lack the yellowish of JBW. In my position, there is no other bush Warbler, and the plumage does not look like other warblers.
So, it is the most likely to be a small Manchurian.

 

[xuky.summer]

Hi John.
Thank you very much for your summary! learning a lot, it turns out that Manchurian also makes a similar sound, which seems to only appear in the non-breeding season? After reading your analysis, I am even more convinced that it is a Manchurian.
Thank you all!