The River Bečva occurs at the confluence of Rožnovská Bečva and Vsetínská Bečva rivers in Valašské Meziříčí. Fishes inhabiting River Bečva present a typical fish composition characteristic for barbel zone. Ichthyological research of its both sources done in 1997 and 1999 has confirmed that the sources are the flows in which the barbel zone communities above the confluence progressively transform into grayling and trout inhabited waters having the high ratio of dominating brown trout, common minnow and, in the highest sections, europian bullhead, alpine bullhead respectively. The low transformation sections having barbel zone species present variable species, abundance and high ichthyocenosis biomass. There are 9–12 species in the River Vsetínská Bečva. The estimated biomass is 200–500 kg.ha-1 and the density 3–6 thousand units per hectare. The River Rožnovská Bečva presents 9–10 species, the estimated biomass 250–610 kg.ha-1 and the density 5.5–18.2 thousand units per hectare. The quantitative parameters of fish populations in the upper source sections are lower showing 1–5 species, the estimated biomass is usually below 100 kg.ha-1, exceptionally even 200 kg and the density ranging from 1.1 to 3.2 thousand units per hectare. Angling activities take place in both sources. There are brown trout and grayling introduced and even the not original rainbow trout in limited numbers. Source tributaries, which are inhabited by alpine bulhead populations, are used for the breeding of brown trout. [ABSTRACT FROM AUTHOR]