Original paper

The importance of oxbow lakes for fish recruitment in a river system

Penczak, T. Zięba


Recruitment, movement and body lengths of 0+ fish were investigated in three oxbow lakes (OL) and two neighbouring sections of the Pilica River (1996– 2000), and also in four OLs and two neighbouring sections of the Warta River (1998– 2000). More juveniles were sampled in OLs than in their parent rivers, especially much more in the Warta River system, where there are wider and deeper connections between the river and OLs. At the end of autumn the majority of species migrate from the channels to OLs, some occupying stagnant and running water in similar proportions, but a riverine species (dace) does the reverse, entering the channel before winter. In 11 cases out of 13, near the end of the growing season (October in Poland) 0+ fish representing different species attained significantly longer body lengths by the same date in the channel than in OLs. This may indicate that recruitment in OLs contributes essentially to the productivity of the channel fisheries, hence separating OLs from their channels by levees requires consideration, because such engineering may diminish fishery yields in a river system.


oxbow lakesparent rivers0+ fishrecruitmentgrowthseasonal movementfishery productivity