Sustainable management and reintroduction efforts of European bison and Przewalski´s horses require solid knowledge about their basic ecology. Since 2010, European bison and Przewalski´s horses have been introduced to the former military training area "Doeberitzer Heide", close to Berlin for restoration purposes. In a 1,680 ha fenced core area, the animals are living without human interferences. This thesis investigated the ecology of semi-wild European bison and Przewalski´s horses under almost natural conditions.<eng>