In collaboration with a number of water boards and consultancy organizations, BioMon partners KWR and BaseClear have developed and applied eDNA techniques to gain insight into the distribution of fish populations and their possibilities in assessing and monitoring the effectiveness of fish passages. Such applications represent a valuable addition to the current, relatively costly and intrusive fisheries approaches and may partly replace them.
Water managers have to periodically determine the state of their fish stocks for the European Water Framework Directive (WFD). Depending on the water type, they determine, in addition to the species composition, the density of fish species in numbers or biomass. New methods that focus on the presence of eDNA are a cost-effective, animal-friendly and possibly more reliable alternative to traditional fish stock sampling for the determination of the species composition. To monitor the species composition of a fish population, a new public available eDNA metabarcoding has been developed, the NL-Fish population scan.
The analysis of various artificially composed mock fish communities shows that the NL-Fish population scan is reproducible with a low detection limit and therefore is highly sensitive. In the systems studied, the NL-Fish Population scan provides an important additional picture of the diversity of species present in relation to the WFD fish stock sampling. With this approach, more species are usually detected, but sometimes some species are also missed.
For more information, see TKI Watertechnology and KWR