25. During the preceding seminars, participants were able to grasp the advantages, performance levels and limitations of biotelemetric tools within the framework of inland fisheries management. In several cases, mainly when the fish size was too small, biotelemetry could not be applied. In other cases, it cannot, on its own, answer all the questions arising in a study project but it greatly facilitates the application of other study and measurement tools. The objective of this seminar, which preceded project definition by participants, was to review the various methods that can be applied to study the behaviour of fish in their natural environment, whilst insisting on their specificity and complementarity with regard to biotelemetry:
- Hydroacoustics, resistivity counters26. This inventory was rounded off with a list of standard questions which should allow participants to make a judicious choice of method to apply to different types of project and was illustrated through some case-studies of projects where biotelemetry had been used, as the main or secondary method, in studying the biology of fish and their relationship with the environment. Experimental procedures and criteria for choosing methods of tagging and monitoring were reiterated in the presentation of these projects.
- Intrinsic genetic and chemical tags (body hard parts)
- External passive tags
- Internal passive tags
- Transponders
