Follow thougths based on your (Howard's link) pics;
There seems to be some differences in the length of tertials and in the primary projection between these species (EOW and Upcher's). The tertials are longer, thus reaches at least in the same line as "the tip of " secondaries in Upcher's, whereas tertials of Eastern Olivaceous does not "cover" totally secondaries. The primary projection seems to be longer in Upcher's than Eastern Olivaceous, but these details should study more.
Also we should look at possible differences in supercilium and loral areas.
In my mind, the supercilium of EOW looks more distinct and sharp in the front of eye and above the eye than in Upcher's, but this based only few pics of Upcher's. The dark loral area is rather wide and thus odd in this 'mystery' bird.
Last edited by hannu : Tuesday 15th May 2007 at 12:32.