How does a dry pond have fish after rains?

There are many kinds of adaptations that animals have to protect their species against potentially deadly things like ponds drying up. Some fish (killifish) have adapted the ability to deposit their eggs in mud or moss, or plants, then when the water dries up, the eggs go dormant. When the water returns, the eggs hatch, thus giving you fish in your pond. Other fish have ability to make mud-nests for themselves (Lungfish). In these nests they lie dormant, breathing air in order to survive. When the water returns, they break out of their mud-nests and begin to swim around again. Still other fish may sneak across land to get to a pond after a rain, some will cross into the pond from other nearby water sources if there is a little bit of flooding, and in other extreme cases, some fish may be introduced by being caught elsewhere, then accidentally dropped into the pond.