Huchon Du Danube

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).

Sexually mature fish migrate upstream into smaller and shallower (0.3-1.5 m deep) streams (Ref. 26170), usually in upper reaches of tributaries (Ref. 59043). Males arrive first at spawning sites. Males defend females against other individuals. Spawning usually occurs during daytime (Ref. 59043). Spawns on gravelly bottom where female makes a shallow hole where the eggs are laid and covered with gravel (Ref. 682). Both sexes covered the eggs with substrate. They both defend the spawning site up to 2 weeks after spawning. Eggs usually hatch after 25-40 days. Larvae stay in gravel until yolk sac is absorbed after 8-14 days (Ref. 59043). Young remain near spawning area feeding on bottom fauna. Spawns with snow melt, in shallow water in Danube or affluents (Ref. 682).

Potamodromous. Migrating within streams, migratory in rivers, e.g. Saliminus, Moxostoma, Labeo. Migrations should be cyclical and predictable and cover more than 100 km.

Dorsal spines (total): 3 - 5; Dorsal soft rays (total): 8 - 14; Anal spines: 3 - 5; Analsoft rays: 7 - 14; Vertebrae: 66 - 72

Rare in lakes. Migrates only during the spawning season. Do not penetrate Black Sea. Generally lives in moving water in deep crevices, in excavations along the river banks or under bridges. It needs pure water rich in oxygen. A cold water, exclusively freshwater salmonid occurring predominantly in running waters and rarely also in lakes and impoundments (Ref. 32707).

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.).

fisheries: commercial; aquaculture: commercial; gamefish: yes