common frog or grass frog (rana temporaria) spawn, the eggs deposited into water, spring

amphibian biodiversity europe poland ranidae aggregates animals aquatic baby behaviour biology breeding child common frog conservation ecology egg grass habitat life march metamorphose nature pond rana temporaria ranavirus reproduction spawn spawning sperm spring water zoology eggs released deposited commof form gelatinous spherical clumps together forming large aggregations april 670 4500