A large salmon (Salmo hucho or Salvelinus hucho) inhabiting the Danube; -- called also huso, and bull trout.

The huchen or Danube salmon (Hucho hucho) is a species of freshwater fish in the salmon family (family Salmonidae) of order Salmoniformes. It is the type species of its genus. Native to the Palearctic ecozone, the huchen occurred originally in the Danube basin in Europe but has been introduced elsewhere on the continent.