I have begun to display some of my soft bodied insects and as I am trying to rehydrate some of them that were plump in the abdomen, they appear to have shrunk and the bodies have sunk into themselves. Does anyone know how to avoid this or what can be done to plump the bodies back up?
"Soft bodied" can come from a number of conditions, but generally, soft bodied insects are kept in ethanol. Adult insects should not need any kind of treatment before being pinned. Nymphs and immature insects should be in ethanol, and I suspect this is what you have. However, they can be freeze dried for a nice effect. One technique that works for females that are full of fatty eggs (such as Orthoptera) is to make an incision on the ventral side with an exacto-knife, and scrape out the contents of the abdomen. Then stuff with cotton, and close the incision. I think you likely have immatures, which should be in ethanol, but this technique would work if you are careful.