Dry winters are bad news for frogs

Ancient ponds on the Greensand Ridge can produce thousands of tiny frogs - so long as the water supply holds up

There are two types of ponds along the Greensand Ridge that runs across from Leighton Buzzard in Bedfordshire into South Cambridgeshire. They are either lined with clay, and fill with rainwater, or they are hollows in the ground that rely on rising groundwater in the winter.

Both provide breeding opportunities for the common frog. The tadpoles have time to mature before some of the ponds dry out in late summer.