A few little touches finished the piece.
First, I added color washes to the background, using thinned fluid acrylics.
I added a minimal background to the bird drawing by adding a bit of the collaged tissue paper behind the bird. I chose a piece of tissue with a very light green. To add it only behind the bird, I put the adhesive all around the bird, bringing it right up to the edge, but not over, the bird. I then pressed the tissue paper in place. When the adhesive dried, I could cut away the part over the bird. I deepened the green around the edge, and added some line work suggesting leaves and twining branches sort of arranged like a crown. I then added another layer of adhesive - Liquitex Mat Gel - around the bird and sprinkled small snippets of silver foil over it.
As for the real background I stenciled the leaves with copper acrylic paint, then added the tiny light turquoise dots.
Finally, I glued the bird onto a piece of corrugated cardboard then glued the cardboard in place. This raises the bird a bit from the surface.