I got a jar of 1 cut up beaver tail and another of cut up fish. Has been in sun for a month. Neither has broken down to a liquid despite hot Temps. I covered top of jar with a paper towel. Both have a strong odor. But are squishy solid by the looks of it. Anything that needed to be added? Should I throw away or continue to leave out?

Very odd, the fish ought to be soup in August temps. Beaver tail takes much longer, and will continue to have solids forever, but there should be some liquid and oil rising to the top of the liquid. I have beaver tails from last spring that are still producing oil, and I haven't taken any out of the ones I did this spring, but there is a good layer of dark oil on top of the this years ones and they had some in less than a month. Beaver tails don't gas off much, I sealed the ones I did this year tight with no issues, fish do gas and need to breathe, but I would put the lid on loosely and then wrap it with cloth rather than cover it with a paper towel.

Some fish has little oil and some only produce watery liquid sludge. As stated fish is prone to break down quickly compared to red meats. Tail pieces take years at times to fully break down. They can keep on giving if you have solids still left in a container. The oil will rise on the tail jar and the fish jar. You should be able to see the darker material on top.