Yes Wallace, you have it.
Your photos show very well the features mentioned by Paul Leader above - a superficial resemblance to Eastern Crowned Warbler in the body but a very different head pattern, grey head with no central crown stripe, weak eye-stripe and thin supercilium, also the white eye-ring and pinkish lower mandible in your third photo.
This photo of Ijima's is taken from The Photographic Guide to the Birds of Japan, and compares well with all the photos above
I think it's worth commenting what an exciting record this is. I believe it must be a first record for mainland China as well as Hong Kong, but it does appear on the Taiwan list I have.
This species has only been found breeding on a few isolated islands in Japan, the Izu and more recently discovered, the northern Ryukyu Islands, as shown in this map also from The Photographic Guide to the Birds of Japan.
The wintering grounds are not well known, there are very few wintering records from anywhere but a few from the northern Philippines suggest that it winters there. It seems likely that the Hong Kong bird came from there, possibly arriving with the rain and strong easterlies last Friday.
The distribution of this species in Japan shows similarities with the
owstoni ssp of Narcissus Flycatcher, which has mostly arrived here in Hong Kong in late March also.
A really good find, and very well spotted by Yiu - otherwise it would have gone unnoticed
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Last edited by wgeoff at 31/03/2015 06:23 ]
