The complex of Karst polje with extensive wet and dry grasslands, flooded lowlands, rivers and underground streams. It includes Licko, Kosinjsko, Gacko, Krbavsko, Crnacko, Stajnicko, Gracacko polje and Bjelopolje. The area also includes hills covered mainly with beech and fir-beech forests. It is one of the most important breeding area for Lesser Grey Shrike and Corncrake in Croatia. The main threats to birds originate from changes in traditional farming, excessive or illegal hunting, river canalization, changes of water level in grasslands and agricultural intensification.