Warbler ID? (1 Viewer)

[GDK]

And with intermediate birds you also need to think about the rare Yellow-streaked Warbler, which is intermediate in size and bill size. Having read the article separating these species in the 1994 HK Bird Report, there is plenty here to suggest Yellow-streaked (and this article suggests Dusky does not show a dark line above the super, while Yellow-streaked and Radde's can do, but its a difficult one to call.
Cheers
Mike

There is a photo of a Dusky in BB 87, Plate 115 P438 (also 1994) showing a dark coronal band and bright edges to the wing.

Like most seemingly, I dont know much about Yellow Streaked, but can it show so little streaking in the central belly, breast, throat and chin? - the second photo shows this off very clearly. The only OB image face-on shows (to me at least!) subtle streaking despite the light flare:

http://orientalbirdimages.org/searc...D=1830&Bird_Image_ID=9204&Bird_Family_ID=&p=4

Svensson (1992) seems to use this as a feature to separate Raddes (and presumably Dusky) from Yellow Streaked, stating there is no streaking on chin and throat in Raddes. Or is that just too crude for us in 2009?

I dont know the answer, not an expert having only seen a few of these glorious phylloscs, but would guess at Dusky for the reasons already provided by others. The leg feature could just be a fact of the very close image, eg they look thinner in the second image to me.


Cheers

 

[MKinHK]

There is a photo of a Dusky in BB 87, Plate 115 P438 (also 1994) showing a dark coronal band and bright edges to the wing.

Like most seemingly, I dont know much about Yellow Streaked, but can it show so little streaking in the central belly, breast, throat and chin? - the second photo shows this off very clearly. The only OB image face-on shows (to me at least!) subtle streaking despite the light flare:


Svensson (1992) seems to use this as a feature to separate Raddes (and presumably Dusky) from Yellow Streaked, stating there is no streaking on chin and throat in Raddes. Or is that just too crude for us in 2009?


Cheers

you would expect a bird in full breeding plumage (the OBI photo was taken in June) to show more yellow streaks than a midwinter bird, especially if the current bird is a first year bird.

The HKBWS article also suggests that YSW shows apricot undertail - which i a pretty good match on my screen (macbook).

I'm not insisting on YSW, but this little trio are not always straightforward, and I'm interested to learn how to sort out these intermediate birds.

Cheers
Mike

 

[anonymous_guy]

Thanks all for your assistance.
Below is a link of an identical bird taken by a birder in China in much brighter/harsher light.
The claim is that it is a Dusky but I think the same issues arise
http://www.cnbird.org.cn/show.asp?mode=d&bh=0975&yonghu=&addr=&sl=20&index=15

and another of a Dusky Warbler taken about 18 months ago 50 yards away from the location of my image .........
http://www.dimension5.com.hk/Up_load/Post/D2X/200709/DWarbler.jpg

The differences occur in the bill & legs, but also the general facial markings.
Hope it is of help.

 

[anonymous_guy]

Went thru Opus & it seems there was a similar discussion in BF with pics in April 2007 here:

http://www.birdforum.net/showthread.php?t=84356

Me.........., I think it is a Yellow-streaked warbler, but that may be coz I want it to be o

 

[Tib78]

I have no experience with Yellow-streaded Warbler so cannot comment on that possibility, but for one thing: shouldn't the strong legs, thick bill-base, and overall colour (including olive wingpanel) be sufficient to rule out Dusky Warbler?

I'll tend to agree on every criteria...compare the subject bird with this typical Dusky pictures:http://orientalbirdimages.org/searc...=1825&Bird_Image_ID=21782&Bird_Family_ID=&p=3

 

[Tib78]

Forgot this one...http://orientalbirdimages.org/searc...=1825&Bird_Image_ID=21783&Bird_Family_ID=&p=2

 

[anonymous_guy]

Thanks everybody for the input.
Neil & I went back to the same spot this morning and whilst I didn't see the chap, heard him all around us......, no recording device but both of us agreed is definitely a "tsic" and NOT a "tac".
Conclude we are looking at a Yellow-streaked Warbler

 

[CAU]

Here's a recording of a Dusky Warbler for reference:
http://www.tarsiger.com/mp3/linad/phyfus_otaniemi_adl_041103.mp3

 

[anonymous_guy]

Thanks "Daniel" (?)
Listening to your recording did at first cast some doubt, but then on reflection think the sound I heard this morning was sharper, more rapid & more clustered.
Mind you, your sound was not the "tak" I was expecting.

 

[CAU]

Thanks "Daniel" (?)
Listening to your recording did at first cast some doubt, but then on reflection think the sound I heard this morning was sharper, more rapid & more clustered.
Mind you, your sound was not the "tak" I was expecting.

No, my name isn't Daniel and it isn't my recording, but you're welcome anyway! Here you can see the full details about the recording:
http://www.tarsiger.com/sounds/index.php?sp=find&lang=eng&order=nro,paiva DESC&species=70220

Mike described the call of a Yellow-streaked Warbler to be a bunting-like "tzik". Many buntings have such a call, among others Little Bunting (the topmost of these recordings is the call):
http://www.tarsiger.com/sounds/index.php?sp=find&lang=eng&order=nro,paiva DESC&species=92080
However, I don't know how close the above linked Little Bunting call is to the call of a Yellow-streaked Warbler, but perhaps Mike can help.

 

[anonymous_guy]

Thanks "anonymous".
Apologies...., there is a "Daniel" in NSN that goes by the handle of "Tarsiger" who commented on YSW vs DW.
Nope...., the above sound bite sounded a bit too shrill.
Guess I'll somehow have to get a recording.

 

[CAU]

Just to add to my previous post, Dusky Warblers often call more rapidly and more clustered than on the recording.

 

[CAU]

Here's another recording of Dusky Warbler (it should start to play automatically, the call is located after the song):
http://www.birdphoto.fi/lajikuvat/phyfus/

Just for comparison, here's a recording of the rather differently sounding Radde's Warbler (the call is again located after the song):
http://www.birdphoto.fi/lajikuvat/physch/

 

[Tib78]

Thanks everybody for the input.
Neil & I went back to the same spot this morning and whilst I didn't see the chap, heard him all around us......, no recording device but both of us agreed is definitely a "tsic" and NOT a "tac".
Conclude we are looking at a Yellow-streaked Warbler

It would be nice to have a recording to confirm the ID.
What a glory for you, if you could get it! 8-P
As far as I know, Yellow-streaked warbler is a little known species, there must be very few recordings of its voice...

Interesting thread anyway, about some species you don't often hear of!

 

[koelko]

Brilliant photo and superb chance for learning about this interesting trio! I have a few points that may suggest DW over YSW and I'd love to hear what everyone thinks.

Leg colour: photos of DW invariably show dark legs (brownish to dark pink, sometimes with contrasting yellow soles, as in subject), but never the pale legs of YSW/Radde's (uniform pink). A few photos doesn't mean all YSW have pink legs, but the dark legs in the subject seems to favour DW.

Bill colour: photos of DW show totally dark upper mandible as in the subject, and photos of YSW seem to always show a pinkish cutting edge to the upper mandible. Also DW bills are often more yellow than pink - again the subject seems to fit DW.

Leg structure: I have no doubt that structure is definite for ID, but photos show that DW legs are laterally compressed ^^""" and the side-view stout legs are within the range for DW. This OBC photo illustrates how deceptive leg thickness can be: note the 'stout' left leg vs the 'thin' right leg: http://orientalbirdimages.org/searc...esult&Bird_ID=1825&Bird_Family_ID=&pagesize=1

Bill structure: bill depth data from Helm's Warbler guide: DW (2.3-2.9mm); YSW (2.6-3.2); Radde's (3.2-3.9) - seems that bill depth is reliable for picking out Radde's, but of rather little use in DW/YSW cases...

Facial pattern: I do agree that this bird's face is unlike the DW I've seen, with rather THICK supercilium becoming diffuse in front of eye, and the black border extending all the way towards the rear - however again I think I haven't been able to appreciate the outliers... http://orientalbirdimages.org/searc...esult&Bird_ID=1825&Bird_Family_ID=&pagesize=1

Having said that I'd look forward to hearing the recording of the bird for more light on this interesting exercise - notably YSW is said to show both bunting-like 'tsik' and DW-like 'tak', while DW seems to just go 'tak'. It'd be nice to hear more on this!

 

[anonymous_guy]

Thanks Koelko.
Seems there is conflict regarding the call as well, but it seems most ppl are heading towards "Dusky" & have just rec'd this from PaulL.
"Despite what you say about the call, to me this is a fairly typical adult winter Dusky Warbler. It does have an obvious dark border above the supercilium which is regularly shown on both Radde's and Yellow-streaked, but it is also well known that some Dusky Warblers can show this.

Yellow-streaked is extremely similar to Radde's and can be very tricky to separate, the separation of Dusky and Yellow-streaked should not really be an issue.

This bird lacks the uniformly pale legs and feet, well defined supercilium behind the eye and thicker bill of Yellow-streaked (and Radde's).

This is also an adult (based on the bright undertail coverts and flanks and white belly); as such an adult Yellow-streaked would show obvious yellow streaks on the underparts - which this bird lacks."

So I'll guess I'll mark it down as a "Dusky".
Thanks everybody for your input.
Guy