Hi Geoff
Its been a very good winter - perhaps my best ever here!
As for the leaf warblers, I'll have a go and invite anybody else to chip and supplement what I write. I'm not sure there's anyone in the world who actually knows exactly which of these we have in Hong Kong, so if a few comments down the line thing all look even more confused I'd be the last person to be surprised!
Please also note that I do not have the up to date papers on the splits - my views are based largely on field observations
Sulphur-breasted Warbler Phylloscopus ricketti
Based on the bird seen yesterday at Ng Tung Chai and the one seen in Tai Po Kau on 4 Nov 2006.
Goodson's Leaf Warbler Phylloscopus goodsoni
Based on birds in Ng Tung Chai this winter, plus the with the Sulphur-breasted in Tai Po Kau on 4 Nov 2006
The key features to look out for are:
1. the all-yellow belly of ricketti (goodsoni always shows some white on the belly, but sometimes not much at all!
2. the black, well defined eyestripes and lateral crown stripes of ricketti differ from (goodsoni, which shows dark grey (NOT black), more diffuse markings, especially the lateral crown stripes.
3. When I saw ricketti and goodsoni together yesterday ricketti gave the impression of being heavier and clumsier - similar to the jizz of Arctic Warbler.
4. According to my understanding, the amount of yellow can be rather variable ranging from almost complete with a few white streaks on the rear belly, to just a yellow-tinged face and throat and undertail coverts.
5. Blyth's show no traces of yellow on the throat, a whitish supercilium and an almost grey central crown stripe.
6. I have no idea about White-tailed nor about the Blyth's type that apparently flicked white outer tail feathers, but Viney, Philipps & Lam mentions occasional tail-flicking in Blyth's.
7. Please note that there are two races of White-tailed Leaf Warbler (ogilviegranti and disturbans), and Emei Leaf Warbler, all of which might also occur. Emai is supposedly inseperable from Blyth's except on song, so keep your ears peeled and learn the songs!
I would welcome any further comments on any of the above.
Cheers
Mike K
Mike KilburnVice Chairman, HKBWSChairman, Conservation Committee