Tough bird indeed. In my limited experience in the tropical forest, photographing birds from below, backlit by the mottled light of the forest canopy, is a very challenging task. Add to that the difficulties of photographing a black bird, and you did well under the circumstances. You captured his throat color nicely, and I like the calling pose.
Difficult environment for any kind of bird image, let alone the extra difficulty exposing black properly under such conditions. Sounds like a very good score for a species that frequent the tree tops, well done