It's a multiplication

      The first warmth for weeks, there's more than a hint of spring in the air and they're at it, the frogs and toads are doing what comes naturally. The Dykes are about to become huge nurseries, first it's great clumps of spawn that seem to appear overnight and if the warm weather holds there'll be masses of tadpoles in there very soon.
      The spawning is a bit indiscriminate because some of these dykes will dry up before the tadpoles turn into frogs or toads so the percentage of survivors from the spawning will be  considerably reduced. Then there are the herons and egrets who will be enjoying a first dip into the season of plenty they'll be standing there  feeding on the spawning frogs then the tadpoles and finally the small frogs without having to make the effort to chase the small fish for their dinner.