Detection of diadromous fish using environmental DNA in Portugal

The high economic value and cultural relevance of diadromous fish make them primary targets for traditional fisheries, that need effective management to ensure the long-term survival of their populations. In Portugal, these species are experiencing a marked decline, primarily due to habitat loss and fragmentation, alongside pollution and overfishing. Accurate monitoring is therefore essential to strengthen the management of diadromous fish within Portuguese ecosystems. Advancements in monitoring methodologies could benefit from more sensitive approaches, such as environmental DNA analysis, which is increasingly recognized as a valuable complement to conventional fish monitoring. However, eDNA-based tools remain largely absent and untested in Portugal monitoring and management of diadromous fish, which we aimed to fulfil with this project.