 48 forms (species and infra specific taxa) of fish have been encountered in the lake, including roach, carp bream, zander, European perch, ruffe, endemic variety of smelt, two varieties of "Coregonus albula" (vendace), eight varieties of "Coregonus lavaretus", a number of other Salmonidae as well as, albeit rarely, endangered Atlantic sturgeon (formerly confused with European sea sturgeon).Commercial fishing was once a major industry but has been hurt by overfishing.After the war, between 1945–1954, the total annual catch increased and reached a maximum of 4,900 tonnes.