I know snake skin bows are considered self bows, because snake skins skins don't provide much protection, only decoration.
Very thin fabric and paper are considered backings.
Where do fish skins fall? Some species are as thin as snake, while some are extremely thick and need to be sanded heavily (yum)
I just figure anything glued to a bow is a backing, but then again I also
think a real self bow can't be made from billets, but lets not go there.
Really, im just not sure what category to enter my sturgeon backed bow for BOM