I understand that this or a similar bird was seen this morning, and there was some uncertainty about whether it was Black-throated or Japanese. Unfortunately, after comparing these photos with photos of Black-throated online, I dont think the bird in these photos is Black-throated (or a hybrid with Naumann's) for the following reasons:
1. Head pattern. The contrast between the black throat and grey back does not seem to be significant enough. Black-throated is fairly pale-backed, which should contrast with a blackish throat.
2. Wing pattern. Photos of black-throated show the wing feathers to be fairly dark-centred with a narrow pale fringe. This is fairly apparent on the median and greater coverts, as well as alula, primaries and primary coverts. The Mui Shue Hang bird appears too uniform in the wings. It also appears that there are usually dark centres to the scapulars on Black-throated, which this bird doesn't seem to show. The tertials of Black-throated are often two-toned grey (outer web) and black (inner web), but these feathers are not clear on the photos.
3. Leg colour. The second photo shows this bird to be pale (pink?)-legged. Black-throated often seems darker-legged, especially males (although this is variable).
4. Flank pattern. The second photo seems to show that the bird is dark on the rear flanks, above the leg. Black-throated seems to be white or pale with well-defined streaks.
5. Structure. Overally, this bird looks to be a small thrush to me, seeming fairly dumpy and round-headed. Overall this fits the structure of Japanese whereas Black-throated looks larger and relatively smaller-headed with a flatter crown.
Some photos of Black-throated for comparison:
http://orientalbirdimages.org/se ... _ID=&pagesize=1
http://orientalbirdimages.org/se ... _ID=&pagesize=1
http://orientalbirdimages.org/se ... _ID=&pagesize=1
http://orientalbirdimages.org/se ... _ID=&pagesize=1
Having said all that, the bird doesn't seem to 100% fit Japanese thrush either, but it does seem closer to Japanese and I suspect that it is a plumage variation of this species rather than Black-throated.
