Huge forests surround the Lake Stechlin and protect it from the impacts of modern agriculture. Therefore the lake is almost free of liquid manure and fertilizers. For the otter, beaver and the extremely rare European terrapin the extended forests offer a perfect refugium. However, also the new settlers, such as the raccoon and the raccoon dogs love this territory and make life difficult for the indigenous animals. A state-of-the-art camera technique, the use of macro optics, light cranes and underwater casing deliver rare and fascinating insights into the world of the crystal clear lakes of Brandenburg.