Standardized molecular methods in biodiversity monitoring for the implementation of international policies

Ongoing research and development projects worldwide aim to build capacity towards implementing eDNA and other molecular methods (e.g. single species assays, eDNA / DNA metabarcoding, metagenomics) in routine biodiversity monitoring, either for the monitoring of species of conservation interest or the status of habitats and ecosystems based on their community composition. We synthesize recent mappings of the biodiversity policy landscape (with emphasis on EU policies), gap analyses of existing biodiversity monitoring programs and reviews of the technological readiness of molecular monitoring methods to identify DNA-based possibilities for biodiversity monitoring in policy implementation.
 
Our preliminary results indicate that gaps that could be targeted by molecular methods include more comprehensive monitoring of arthropods and other invertebrates, fungi and lichens as well as applying molecular community monitoring to assess the structure and functions of ecosystems. For freshwater systems, zooplankton is among the most important poorly known taxa. Small lakes, streams and springs are the most important poorly known habitats.
 
Molecular data would be well suited for increasing the taxonomic and spatial coverage of in situ monitoring data to support and complement remote sensing -based modelling, assessing short-term temporal trends and revealing pressures and threats behind biodiversity patterns and trends. Our results shows that the majority of molecular methods have yet to reach the highest levels of technological readiness. However, in many cases the bottleneck for upscaling are not technological shortcomings but rather the fragmentation of the field and lack of joint collaborative effort towards widely shared best practices and international standards in this fast-developing field.
 
At the same time, biodiversity loss is accelerating, and more comprehensive, internationally compatible biodiversity data is urgently needed for timely decision making and for monitoring the impact conservation and restoration actions. We conclude that while further research and development of methodology is needed, the pressing knowledge needs of biodiversity policies motivate launching large-scale molecular monitoring programs sooner rather than later. This could help improve the likelihood that the ambitious targets set up by policies are reached. Further, we stress that international cooperation and standards are key to avoid unnecessary plurality of methods and incompatible results.