OK, so you like a good fish dinner. You took your catch home, cleaned it, cooked it and ate it. But chances are, unless you’re a shark, you probably didn’t eat the whole fish. Don’t throw the rest away. We’re not suggesting that you make jewelry out of the bones. Instead, compost the fish parts with plant waste such as sawdust, peat, wood chips, leaves or bark. Microorganisms in the pile will feed on the waste, and over the course of several months, convert it into rich humus that is great for growing plants. Don’t worry about the smell because heat from the microbes will pasteurize the pile, eliminating the odor, as well as any disease organisms.

Source: http://animal.discovery.com/adventure-fishing/sustainability/top-5-sustainable-fishing-practices-06.html