ECOLOGY OF YOUNG (0+) HUCHEN, Hucho hucho (L.) (Salmonidae), PLANTED IN TWO MOUNTAIN STREAMS

Abstract

Dispersion of underyearlings in mountain streams depends on their size - the smallest individuals occupy the shallowest microhabitats, moving into deeper parts with increasing size. Gradual migration of young huchen to lower sections of streams, in spite of food abundance, depends probably on some abiotic (mainly water temperature) and biotic factors i.e. initial fish density, the resulting territorial behaviour and other social interactions.