This was meant to look as though he was straining to get out of the hole, but it was difficult to "map" the geometry of the hole to design the right position of the arms etc. In the end, I just made it in bits and hoped I could glue them into a convincing attitude.
The bits are stuck together with Gripfill and are threaded onto a metal bar. I squirted foam filler into the hollow in the tree to hold everything in place. I used turquoise vellum, rubbed off a bit, to glaze it.