I have heard of the idea of birds or ducks naturally stocking the pond but always thought this to be a myth. I was wondering if anyone has could provide me with some help.
usually, if the pond has been there and isn't built by man, it is connected somehow to another water source. even if there isn't a connected source now, there could have been hundreds of years ago, thus the fish reproduce in the pond and there you go. Alternately eggs could be carried and dropped by birds, turtles, frogs, toads, etc. Also sometimes people do buy fish to stock natural ponds.