ID help requested: Thrush seen in Chongqing, China (1 Viewer)

[Iwan (Bob) Roberts]

Dear Asia Birders
I am pondering over this juvenile thrush photographed in a park (altitude ~400m) in Chongqing, China on 14 July 2023. My question is whether it is a Black-breasted Thrush or a Japanese Thrush. The former breeds at higher altitudes and does not normally occur this far north, while the latter is present in Chongqing at low densities in summer (Sid Francis pers. comm). There is an illustration and photograph of BBThrush here Merle à poitrine noire - Turdus dissimilis which to my mind supports the idea of BBThrush, as does the sketch of a juvenile bird from Viet Nam in the same article however see also

https://flic.kr/p/gmZq28

which also shows much similarity.

I woiud appreciate if anyone with experience of the juveniles of these apecies could comment.
Iwan Roberts

[email protected]

 

[Iwan (Bob) Roberts]

Accidentally included a streak-breasted Scimitar-babbler, please ignore that image.

 

[andyb39]

I'm not sure the orange wash on the flanks is extensive enough for Black-breasted, although it's quite dark on the upper parts. Is Grey-backed possible here?

 

[Ratal]

Grey-backed Thrush gets my vote. Pic added to explain why it is so.

 

[johnallcock]

It's a long way (c. 2000km) outside the breeding range of Grey-backed, so I don't think that's likely.

I'm not familiar with these species in juvenile plumage, but I'm inclined to agree with Andy that the orange is not very extensive for Black-breasted and is within normal range for Japanese. The spots are not typical for Japanese (at least compared to adults), but spotting on juveniles does seem a bit more blotchy than on adults and this doesn't look too far off other photos of juvenile Japanese. On balance, I think I'd say this was Japanese.

Some more comparison photos in case they help:
Black-breasted: ML589665721 Black-breasted Thrush Macaulay Library
Japanese: ML594135251 Japanese Thrush Macaulay Library ML594135211 Japanese Thrush Macaulay Library

 

[Iwan (Bob) Roberts]

It's a long way (c. 2000km) outside the breeding range of Grey-backed, so I don't think that's likely.

I'm not familiar with these species in juvenile plumage, but I'm inclined to agree with Andy that the orange is not very extensive for Black-breasted and is within normal range for Japanese. The spots are not typical for Japanese (at least compared to adults), but spotting on juveniles does seem a bit more blotchy than on adults and this doesn't look too far off other photos of juvenile Japanese. On balance, I think I'd say this was Japanese.

Some more comparison photos in case they help:
Black-breasted: ML589665721 Black-breasted Thrush Macaulay Library
Japanese: ML594135251 Japanese Thrush Macaulay Library ML594135211 Japanese Thrush Macaulay Library

I'm not convinced by Grey-backed Thrush because apart from the range, I don't think the chest background colour matches. Initially I thought that as BotW mentioned the orange spotted wing bars on juvenile Black-breasted Thrush it might be an extralimital BBT but after personal communication with Sid Francis who has recorded breeding Japanese Thrush in Chongqing during bird surveys (and I counted 5 records on eBird) and who also thinks it is Japanese Thrush I think on balance it has to be a Japanese Thrush. Thank you all for your comments and thoughts, greatly appreciated.