Fish monitoring

Fish monitoring refers to tracking fish migrations and observing fish behavior.

The aim of monitoring is usually to use the observations made to draw conclusions about the success of measures implemented or to identify areas for improvement.

A wide variety of techniques are used for this purpose.

© Stefan Ludwig

Fish passes, for example, are equipped with fish traps to see whether they are accepted by fish at all and which fish species and sizes use them.

Video systems are used in waters where visibility permits. Sonar systems are used in waters with high turbidity, for example to observe the behavior of fish at the entrance to a fish pass.

© Screenshot Stefan Ludwig

Another important part of fish monitoring is the tagging of fish. Many different tagging techniques are used for this purpose.

Fish are marked with colored dots or tags of various types. A range of transmitters and data storage devices are also used for fish monitoring.

An overview of these tagging techniques can be found here.