After our return I tried to find out more about these insects. According to Wikipedia (and for my surprise) they are closer relatives of the cockroaches then ants.
As stated in https://creation.com/termite-mounds in dry season termites live underground where the temperature is almost constant. In flooded areas though they live in the mounds even in dry season. This implicitly means that somehow the water of flood does _not_ destroy the mounds though it is not explained why. Does anybody happen to know why does the termite mound survive the food?
|inside the mound|