Project
SoleDNA: Characterising a data poor sole stock using DNA and eDNA (SOLEDNA)
SoleDNA is about genetic techniques to efficiently and accurately clarify the stock identity of sole. It also involves research into the 'free' DNA (eDNA) of sole and plaice in the water, and to what extent this can be used to determine the presence and biomass of both sole and plaice. When this innovative determination of presence and biomass of a fish species becomes a reality, science will have a valuable alternative to collect more, and thus more correct, data about (data-poor) fish stocks in a non-invasive way.
Research approach
Examining the stock identity of a fish population is currently complex. Researchers are mapping the genetic diversity of sole, within and between ICES areas. To do this, they sample tissue from sole originating from different areas, for further DNA analysis. After sequencing the DNA, the millions of sequences are filtered and linked to the reference genome of sole and analyzed using bioinformatics. In order to now focus the eDNA technique as a proxy for sole and plaice detection and biomass, ILVO has long been making a special data collection during the ongoing ILVO campaigns at sea: sea water is sampled at various locations close to the seabed. Detailed catch data from these locations are available for sole and plaice. The filtered eDNA patterns are tested against the known distribution patterns of both species. The seawater is filtered and the eDNA is isolated directly from the filters, after which quantification can be done using the digital droplet PCR (Biorad). This method uses species-specific primers and probes that replicate only sole or plaice DNA.
Relevance/Valorisation
The relevance of this project is in the strengthening of science-based policy actions. It was agreed that if the results indicate the need for concrete changes in the current management of data-poor fish stocks and more specifically the sole stock in 27.7h-k, there will be proactive discussions with the competent authorities. The national policy (Flemish government - Department of Agriculture and Fisheries - Fisheries Service) is one of these bodies. They could use the project results in quota and Brexit negotiations. ICES, as the organization responsible for the stock assessments, will also be informed in due time so that possible concrete changes can be implemented in the advisory process.