Tadpoles in the Office Pond – So Far so Good
Pond watching during our breaks from working at Everything Dinosaur, is very much a favourite pastime of the staff. It is pleasing to note that even though the pond was cleared out last Autumn, the removal of much of the pond weed and the disturbing of the bank side vegetation does not seem to have affected the wildlife at all.
The pond snails seem to be thriving, although we have counted more Ramshorn snails than Pond snails this year for the first time. The invertebrate life seems to have flourished as well with the first of the Damsel flies emerging as winged adults over the last ten days or so. They really are a joy to watch as they whirl and fly around the pond. The tadpoles are much more visible than last year. Despite having fewer places to hide they seem to be doing well also. We have noted two distinct sizes of tadpole, although we know that they are from the same batch of frogspawn laid earlier this Spring. The larger tadpoles are bigger overall and have proportionately larger heads. We have speculated that some tadpoles may adopt a more predatory role in the pond compared to others and they are genetically predisposed to develop larger jaws as they attack and eat other pond animals.
We have read about this but we are not sure whether it is true, that in the Common frog (Rana temporaria), and perhaps in other genera, there is a tendency for some of the tadpoles to develop carnivorous habits and it is these animals that have the best chance of surviving and making it to the froglet stage. Today, one of our colleagues reported they had seen one of these larger tadpoles with back legs, the first time that this has been observed.
Perhaps these larger, predatory tadpoles grow slightly faster on their protein rich diet and therefore complete the metamorphosis into frogs that much quicker.