I am interested by this bird. Do you have any more photos?
The underwing is barred, but to me it does not seem as heavily barred or as dark as I would expect on a Far Eastern Curlew; the underparts seem to be rather whitish towards the rear, rather than buff as on Far Eastern; and there seems to be a hint of white on the back, suggesting Eurasian Curlew. The mid-winter date also makes Eurasian more likely than Far Eastern (although a few Far Eastern do overwinter).
But Eurasian Curlews in Hong Kong usually have a completely white, unbarred underwing pattern. On your bird, the underwing barring is closer to the appearance of the subspecies arquata, which is usually found in Europe and has not been recorded in Hong Kong. There have been sightings before of birds resembling arquata, but I don't think it has ever been confirmed that these are not the result of variation in the local subspecies orientalis. Author: wingwing Time: 24/05/2016 17:14
Thank you for posting the extra photos. These show that the bird is a Eurasian Curlew, as the white on the back can be seen extending between the wings.
I will need to read more about the separation of the subspecies of Eurasian Curlew. Most resources I have seen seem to suggest that the local subspecies orientalis should have a plain white underwing, but I wonder if there is some variation, or if there is some mixed breeding between subspecies. There are also other differences between the subspecies in terms of size and underpart pattern.
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