"What happens to tadpoles?", he asked, knowing well that they grow into frogs - if they are not eaten by some enemy in the water or even fished out by a heron or other bird. He asked, he said, because for some years a small artificial pond in a garden he used to have in Dublin nearly always got a quota of frogspawn, yet never, he swore, did he see one of the tadpoles evolve into a frog. No. Once he saw a tiny frog come out and then vanish. He remembered from his schooldays, when a teacher of nature studies used to have a large glass tank in the classroom with frogspawn brought in January or February. The tadpoles duly emerged and were eye-catchingly wriggly. Needless to say, there were pond weeds in the tank and a rock on which an emergent frog might climb. But come the Easter holidays or some later half-term break and the tank and all vanished, the wrigglies returned to the wild.
A copy of the Field Book of Country Queries (1954, Michael Joseph) tells of an experiment in which two lots of tadpoles were taken from the same pond. One lot, kept under glass in the house, developed normally into frogs. The other lot, kept in a shallow six-foot stone trough containing water lilies, remained in the tadpole stage. Normal time for the egg-to-frog state, the article says, is about the 85th day after egg-laying. But to come back to that garden pool. If a heron had made raids on it, you could understand the lack of froglets, but no heron ever came. And the blackbirds and other birds doing their evening ablutions in the water hardly got them. Of course, as Cabot tells us in his new Ireland, a Natural History, while a high percentage of eggs hatch into tadpoles, fewer than 1 per cent survive to young froglets. And there will be plenty of enemies out there.
Another aquatic creature which small boys would come across in the years before the present conservation laws came into being was the newt. One friend says he remembers, as a very small boy, visiting a nearby pond in search of frog-spawn and seeing a wonderful sinuous creature in the water, a sort of water-lizard, which he was able to identify later as a newt. He described it as having a crest and a lovely reddish speckled breast. it was a long time ago, the pond has vanished under houses. Back to the first question. Why did the original questioner never see a tadpole grow into a frog, save one? Anyway, in the bogs and marshes outside the urban scene, frogs are aplenty, it seems. Y