Determining the effects of species, environmental conditions and tracking method on the detection efficiency of portable PIT telemetry

The efficiency of portable passive integrated transponder (PIT) telemetry at detecting five fish species in a small river was evaluated under different environmental and tracking conditions. Significant differences between species were apparent, with detection efficiency varying between 0.7% (Leuciscus leuciscus) and 43.1% (Salmo trutta). Conditions of reduced flow and tracking in a downstream direction significantly increased detection efficiency for salmonids, while time of day had no significant effect for any species.