Observations of a chamber fish-pass at the lowest situated dam and power station on the Odra River were conducted between March 2002 and February 2003. Twenty two fish species were recorded during 21 catches at the pass, with dominant species Alburnus alburnus (90.8% of individuals), Rutilus rutilus(4.9%) and Gobio gobio (1%). The most intense upstream migrations were observed in spring and early summer during the spawning period of most species occurring there. The migration intensity of most analysed species was positively correlated with water temperature. No potamodromous fishes were observed in the pass at water temperatures below 8 ºC. The only diadromous species recorded were Anguilla anguilla, Vimba vimba and Salmo trutta trutta, all represented by very few individuals.