Environmental determinants of residence area selection byBarbus barbusin the River Ourthe

A biotelemetry experiment was designed to determine whether the selection of a residence area by adult barbel Barbus barbus (Cyprinidae) was dependent on the availability of physical habitat features, on the presence of fish shoals and/or on the presence of specific partners. The experiment took place in 3.0 km stretch of the River Ourthe (Belgium), where the latter features had been characterised by habitat and electric fishing surveys (1 190 fish ≥ 15 cm, at 265 locations). Six barbel (34.8–49.5 cm) belonging to a single shoal of 34 fish were tagged with 40 MHz radio transmitters, transplanted in pairs at different distances (−1 km, −30 m, +1 km) from the capture site and tracked from 3 September to 7 October 1990.