It seems to me too crowded to the right just to meet the challenge theme. It's too busy behind the bird. Having the bird on the left perch would be nicer IMHO, but I suppose that was out of your control.
the negative space is too distracting from the main subject. It seems that there are two backgrounds, the green and the object. the position on the low right is a good choice. A better choice may be only the green background but obviously I think that the bird wasn't agree :) I really like the colours and the sharpness 7