Overview: When spring comes, strange sounds fill the peaceful water world of Teichlausitz in the extreme south-east of Germany. What sounds like someone blowing into a bottle is the courtship call of the bittern, which can be heard from miles away. However, the extremely rare bird can hardly be spotted: if it feels observed, it stretches its head and beak straight up and moves gently in the wind like the reeds. In addition, the brown and black plumage makes the bittern almost invisible. Otters and elks also feel at home in the border region between Brandenburg and Saxony. And not far away, the overburden heaps and mining lakes of decades of open-cast lignite mining offer numerous wild animals valuable retreats. Recultivation areas and former military training areas are now home to animals that have all but disappeared in this country. Iridescent bee-eaters and hoopoes breed on the heath because they find plenty of insects there.