Environment / Climate / Range
Freshwater; benthopelagic; potamodromous (Ref. 51243). Temperate; 6°C - 18°C (Ref. 2059); 50°N - 44°N, 8°E - 21°E
Length at first maturity / Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 150 cm TL male/unsexed; (Ref. 11243); common length : 70.0 cm TL male/unsexed; (Ref. 682); max. published weight: 52.0 kg (Ref. 719); max. reported age: 15 years (Ref. 682)
Morphology | Morphometrics
(total): 3 - 5;
soft rays: 7 - 14;
Vertebrae: 66 - 72. Distinguished from other species of Salmonidae in central and eastern Europe by the following combination of characters: lateral line with 180-200 scales; no red spots and white fin margins; head dorsally flattened and long ( 22-24% SL); body roundish; caudal fin deeply emarginate; large size (in undisturbed areas); usually 13-19 gill rakers (Ref. 59043).
Europe: Danube drainage. Introduced into other European river basins when their numbers declined due to ecological changes in the Danube. Appendix III of the Bern Convention (protected fauna).
Usually solitary, inhabits deeper regions of swift flowing streams with oxygen rich waters. Adults are territorial but not solitary (Ref. 26170). Carnivore. Juveniles feed mainly on invertebrates and adults mostly on fishes, but also prey on amphibians, reptiles, small mammals and waterfowl (Ref. 26170). Important sport fish with minimum size of catch from 50-55 cm. Transplantations of young artificially incubated and reared fish have not been successful. Depletion of stocks due to overexploitation, industrial pollution, waterway redirection and badly designed or non-existent fish ladders in dams and reservoirs. Territorial, but migrates short distances upstream for spawning (Ref. 556). Reported to be one of the biggest freshwater fishes of the world, reaching a length of over 2 m and weight of over 100 kg (Ref. 26170); which is probably erroneous (A. Mangold, pers. comm.).
Kottelat, M., 1997. European freshwater fishes. Biologia 52, Suppl. 5:1-271.
IUCN Red List Status (Ref. 90363)
Threat to humans
Fisheries: commercial; aquaculture: commercial; gamefish: yes
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on empirical models
Phylogenetic diversity index (Ref. 82805
= 0.5312 [Uniqueness, from 0.5 = low to 2.0 = high].
Trophic Level (Ref. 69278
): 4.2 ±0.74 se; Based on food items.
Resilience (Ref. 69278
): Low, minimum population doubling time 4.5 - 14 years (tm=5; tmax=15).
Vulnerability (Ref. 59153
): Very high vulnerability (77 of 100) .