Tagging Techniques

Different techniques for investigating fish migration are presented here. For more detailed information please click on photos and you will find a detailed and illustrated descripton of the technique.


Report tagged fish



Why are fish being tagged?

Tagging allows to investigate migration behaviour of fishes.

Valuable information on numbers and migration routes of fish can be acquired. We also call this "Monitoring".


How are fish being tagged?

Fish are being marked or tagged, among others, using colour dots on the skin, small labels, fin clipping and transmitters. Transmitters can be attached to the outside or also inserted into the fish body.  

You'll find an overview of the usual marking methods on the right side of this page. By clicking on the photos you'll get additional information about the respective method.


What to do when I have caught or found a tagged fish?

Have it registered under all circumstances! Find the registration form here! Fish Registration Form

The scientists depend on your help. Every registration is very valuable!



Click on photo for detailed information

VI Fisch

 Number Label (VI-Tag)

Smolt Oker pfeil
Colour Marking 




Reward Carlintags


 Hdx 25


Nedap gross


Acoustic Transmitter


Radio Silkeborg1

 Radio Transmitter












3 interesting examples for fish migration routes.