• cyprinids;
  • insectivores;
  • lowland river;
  • migration;
  • telemetry

Seventeen individuals of ide Leuciscus idus were radio-tracked weekly from September 2003 to September 2004 in the River Elbe, Czech Republic, to examine migration patterns and the influence of environmental factors on their diurnal behaviour. Of the 10 environmental factors measured, L. idus were significantly influenced by turbidity, which increased diurnal movement and the home range size of the species. The peak of longitudinal movement occurred in the spring, indicating pre-spawning migration. Migrating fish moved downstream and later returned upstream to the vicinity of their original locations, displaying a homing behaviour.