Application of novel genetic tools for fisheries conservation and management

I created two novel eDNA assays, for a marine invader, <i>Crepidula fornicata</i>, and for a threatened native species, the European oyster, <i>Ostrea edulis</i>, thus adding to the tools available for monitoring and/or conservation and subsequent management of these species. Results generated illustrated that tidal state and season can impact results, but also that eDNA analyses may not be suitable for all species. The use of eDNA for routine monitoring of an invader, <i>Dreissena polymorpha</i> was investigated, with eDNA successfully detecting <i>D. polymorph</i>a in known areas but did not find new populations.

These findings demonstrate that eDNA methods should remain as supplemental measures, until uncertainties have been addressed. Finally, I demonstrated the importance of genetic analysis in hybridisation zones. I applied a multiplex qPCR assay to presumed native <i>Mytilus edulis</i> individuals.

Findings indicate that, for the first time, an <i>M. edulis</i>/<i>M. trossulus</i> hybrid was discovered in Northern Ireland, with additional <i>M. edulis</i>/<i>M. galloprovincialis</i> hybrids and <i>M. galloprovincialis</i> individuals discovered for the first time in Carlingford and Larne loughs, emphasising the importance of genetic tools. Ultimately, this thesis summarises how we can utilise existing genetic tools for conservation and management of aquatic environments.<br>