Aspius aspius (Linnaeus, 1758)

Occur in open water of large and medium-sized lowland rivers and large lakes (Ref. 59043). Adults inhabit lower reaches of rivers and estuaries (Ref. 30578). Prefer to stay near bridge pillars, near tributaries, under weirs, in deep currents and overgrown parts of river and in quiet bays of river bends (Ref. 9696). One of the rare cyprinids which is piscivore; also prey on small aquatic birds. Juveniles are gregarious predators while adults hunt in small groups or are solitary. Juveniles and adults feed mainly on fish, especially on Alburnus alburnus or Osmerus eperlanus (Ref. 59043). Migrate upstream in tributaries for spawning in April-June (Ref. 556, 30578). Spawn in fast-flowing water on gravel or submerged vegetation. Lake populations migrate to tributaries; semi-anadromous populations or individuals (Terek) forage mainly in estuaries and freshened parts of the sea, migrating to rivers only for spawning. Begins spawning migration in second half of October (Terek) and overwinters in the lower reaches of river. Hybridizes with Leuciscus idus. Threatened due to alteration of river morphology (Ref. 59043).

Large rivers draining to North Sea (Weser, Elbe), Baltic Sea (southern tributaries, Norway east of Oslo, southern Sweden, Kokemren drainage in southern Finland), Black Sea, Sea of Azov and Caspian Seas; Aegean Sea, from Maritza to Lake Volvi drainages. Absent in Black Sea basin south of Danube and Rioni (Georgia) drainages, but present in Turkey west of Ankara. Introduced in Rhine, Northern Dvina and Lake Balkhash (Asia). Identity of populations of Aral Sea remains uncertain.

Europe and Asia: large rivers draining to North Sea (Weser, Elbe), Baltic Sea (southern tributaries, Norway east of Oslo, southern Sweden, Kokemären drainage in southern Finland), Black Sea, Sea of Azov and Caspian Sea; Aegean Sea basin, from Maritza to Lake Volvi drainages. Absent in Black Sea basin south of Danube and Rioni (Georgia) drainages, but present in Turkey west of Ankara. Introduced in Rhine, Northern Dvina and Lake Balkhash (Asia) (Ref. 59043). Appendix III of the Bern Convention (protected fauna). The subspecies Aspius aspius iblioides was previously recognized by authors for the Aral Sea (Ref. 13403).