kkoel

I'd agree with George. To me, the shape of the bird's head is reminiscent of Eastern Crowned but the lack of crown stripe would rule that out. The thick supercilium and faint eyeline at the lores would also favour Greenish over Arctic. It's interesting to note that western subspecies of Greenish do show very pale legs, while some Two-barred can show really dark legs, there is enough variation in leg colour to show up pale on a bright photo as this. I'm sure experts can enlighten us more on the current thinking about Greenish warbler subspecies/species that may occur in Hong Kong?

kkoel

Thanks for John's opinion. OBC pics show that the mandible length plus orange tip are indeed consistent within Eastern Crowned, but dark tip and shorter bill length are consistent within Greenish. Perhaps I was a bit rash in noting that the lack of crown stripe 'rules out' Eastern Crowned: it's imaginable that the crown stripe can wear off considerably towards winter (even our 'textbook' notes that).

I won't find it surprising to discover previously southerly-wintering birds wintering in HK though!