Bob - In addition to what Fletch said, there is another reason for not using hybrid sunfish (most often bluegill X green sunfish) if you want food for your bass. Part of the reason for doing this cross is to get offspring that are primarily male. If you cross a pure male bluegill with a pure green sunfish female, almost all of the offspring will be male. Then, supposedly, you don't get reproduction and the sunfish don't overpopulate your pond.
So, if you are managing for largemouth bass, you want a sunfish such as the bluegill to reproduce, because they are providing food for your bass.
The hybrids often don't reproduce very much, and then when they do, you get these mixed genetics of future generations that Fletch mentioned. Often, they don't grow as well, and seem also not to reproduce as much.
I think a lot of the pondowners who favor the hybrid sunfish like to feed them pelleted food, and get some dandy-size panfish that way. Most of them probably have to re-stock new F1 hybrids (first generation) every couple of years. I was not aware that some people try to remove the "hybrid swarm" after a while, but that makes a lot of sense to me.
Dave
