Busy Frogs

Log pile

The Common Frog (Rana temporaria) or Frog in Irish is widespread.  Both male and female frogs have recently woken from hibernation in stone walls, under logs, compost heaps, ditches and ponds and are now returning to the ponds or ditches in which they were born (1).

Frogs and spawn

Males arrive first and start croaking to attract females. These lay about 2000 eggs each which are fertilised externally by the males (2).  The emerging tadpoles have gills and eat the protein rich jelly surrounding the eggs.  As tadpoles without legs, they eat algae and pond plants.  When they develop hind legs after about five weeks their lungs begin to develop.  They become carnivores and eat water insects.  After about fourteen weeks they develop into froglets with four legs and no tail.  They can now breathe through their lungs and skin.  After three years they are fully grown and capable of breeding.

Heron near canal Credit Paul Phipps

Frogs are amphibians which means they can live on land and in water. Only two other amphibian species are found in Ireland: the smooth newt and natterjack toad. The latter is an endangered species in Ireland and is found only in Kerry and Wexford.  Frogs eat slugs, worms, snails, insects and spiders and are eaten themselves by owls, herons, foxes, otters, gulls, stoats, badgers and pine martens (3).
Contrary to an ongoing myth, spawn can be collected in Ireland by teachers and kept in aquariums in the classroom for observation.  The licence for doing this can be downloaded from https://www.npws.ie/sites/default/files/general/frogspawn-licence-2016.pdf  However, it is important that the tadpoles or froglets are returned to the same pond from which the spawn came in order to prevent the spread of diseases.