wgeoff

This bird looks like a Radde's-type warbler from the overall colour, lack of wing bar, long supercilium and bill shape, but it was quite yellow underneath, particularly in sunlight, and also streaked. I did not hear any call.

Could it be a Yellow-streaked Warbler?



Photos taken on Po Toi on Tuesday 6th October

[ Last edited by wgeoff at 6/01/2010 15:07 ]

kkoel

The bird has no buff vents, no buffish fore-brow, brownish back without olive, and the bill tip is rather sharp. I'd go for Yellow-streaked - and I'd be happy to hear expert opinion. In any case, great bird!!

lmichael

I consider that this is a Radde's Warbler. The legs are obviously strong and this, alone, is probably enough to rule out Yellow-streaked. In addition the bill is relatively heavy, I think too deep for Yellow-streaked. On colouration, this looks like a typical Radde's too: first year birds of both species show yellow streaking but this is typically more  obvious on Yellow-streaked and I would expect it to be more apparent than on this bird.

Mike Leven

lpaul

I had some extremely interesting and productive correspondence about an interesting Radde’s Warbler in the UK last autumn with Martin Garner.  Ian Lewington checked some specimens at the British Museum at the time and Martin forwarded me his comments.

Based on this and my paper in the 1994 HKBR I’d suggest the following are the main criteria for identifying a Yellow-streaked Warbler:

•        A metallic bunting-like tzic call (a soft quip in Radde’s, similar to one of the calls of Russet Bush Warbler)
•        A dark brown ground colour to the breast/belly forming a darker breast band (typically whitish on Radde’s, and rarely showing a breast band)
•        Pale throat more clearly demarcated (less so in Radde’s)
•        Supercilium often whiteish behind the eye (variable in Radde’s)
•        Supercilium often more distinct in front of eye
•        Upperparts more brownish on average (more olive on average in Radde’s)

Bill structure is a difficult feature to use as many Radde’s (presumably females) have smaller bills.

Note also how the bill structure varies in the photos of this bird, looking very thin in one photo.

On balance, I would say that this is a Radde’s Warbler.

wgeoff

Thanks for these detailed replies which are very helpful.

It seems that Yellow-streaked is a particularly difficult bird to tie down unless you hear the call. This is my second attempt at the species, maybe it will be third time lucky. I will be listening carefully for the call next time.