Late autumn, the first frost is in the air. This is the time when the days get shorter and the nights get long and cold. The yellowing leaves have not yet fully dropped, but the swamp is already covered with a thin crust of ice on which here and there you can see the footprints of some of the braver “natives” – nutrias, beavers, weasels – who crawl out of their holes every night and head off in search of food.