 you also get fish populations that grow from natural dispersal as well every time a heron walks through the shallows gets some eggs on its feet flies to the next pond those eggs fall off they could possibly hatch there a long story short was i had a great farm pond accessible to me that had some pretty good size largemouth bass in it at that time i would say four you know to five pounds could be had from this farm pond and as a kid that's a big fish