Europe and Asia. North, Baltic, Black, Caspian and Aral Sea basins, as far north as southern Sweden and Finland; Aegean Sea basin in Maritza and from Struma to Sperchios drainages; Turkey. Absent from the rest of Mediterranean basin. Now widely introduced and translocated throught Europe and Lake Balkhash basin in Kazakhstan. Several countries report adverse ecological impact after introduction. In Appendix III of the Bern Convention (protected fauna). |