The first spring after the new waterlily pond was built, three years ago, we had a very good hatching and development of frogs spawn. The following spring the spawn completely failed, we assume, due to it being frosted.
This year the pond is very lively with frogs and there is more spawn than year one, presumably boosted by the successful hatching and development of that year. I have placed an old window over part of the spawn to help protect it, if we have frosts and from predators. Something, presumably a fox dragged some out onto the grass while trying to catch and kill the frogs.