In addition to the lack of a supercilium, Northern Sparrowhawk can be eliminated due to the broad dark bars on the uppertail and the broadness of the bars on the underside of the primaries (these are narrow and less well defined in Northern). The structure eliminates Besra (note the long gap between P2 and P3, and I think the distance between P5 and P6 fits Japanese better), and fits Japanese, and although the dark bars are usually narrower than the pale bars on the upperside of the tail on Japanese, this is not always the case and some birds show a tail pattern comparable to this bird. So, I would go for Japanese.
[ Last edited by lpaul at 11/10/2010 16:42 ]
