I gotta ask about this rumor running around our parts. I have heard that you don't want to clean fish and let the runnoff go into your pond or throw the carcass in your pond. "They say" (whoever they are) that there are something like hormones, pheremones, enzymes, or chemicals resident under a fishes skin that trigger the termination of spawning. The idea is that if you let the huge amount of these chemicals from a cleaned fish get into a lake or pond that it can stop all spawning activity over an entire lake. Any experts know if this is true. If it is, you may not want to clean fish near the pond. I've heard that here in MN we are told not to clean fish and throw the carcass in the lake for this very reason.
