It was interesting to observe the different feather markings of the male sub-adult Asian Koel bird (Eudynamys scolopaceus). I have attached 5 photos to present various views of the feathers. These photos were taken over various times and therefore may not be the same bird.
The first 3 photos are flight shots which showed that the white-tipped feather markings appeared on 2 sets of feathers; the greater primary coverts and the greater secondary coverts. These feathers were also dark brown, contrasting with the others which were glossy dark green. Photo 4 shows clearly the contrasting colours when the bird is perched on a branch. These brown feathers will eventually turn to the glossy dark green feathers as the bird matures.
Article by Thong Chow Ngian.
11 November 2021.