Aquaculture Canada and WAS North America 2022

August 15 - 18, 2022

St Johns, Newfoundland, Canada

MONITORING BAY-SCALE ECOSYSTEM CHANGES USING eDNA IN ENVIRONMENTAL SAMPLES

 

Anaïs Lacoursière-Roussel, Kimberly Howland and Marc Trudel

anais.lacoursiere@dfo-mpo.gc.ca

 



 Aquaculture  is intimately linked to the functioning of the receiving ecosystem through various direct and indirect interactions and feedbacks.  To date, aquaculture research has predominantly focused on near-field benthic effects. Limited research has documented bay-scale ecosystem impacts, including the potential impacts at higher trophic level.

aquaculture ecosystem interactions requires a method and

 a  sampling  design able to detect changes in ecosystem structures over time. With its power to increase coastal survey coverage, environmental DNA (eDNA) is increasingly employed to  monitor ecosystems and support decision-making.  However, little is currently known about  how the detection rate  of coastal eDNA  changes seasonally and regionally in relation  to biological and physical factors. As a result, there is no guidance on optimal sampling periods to design eDNA studies for most species .  Better understanding how factors alter  eDNA presence are not only fundamental to optimizing eDNA project planning and avoiding false negatives, but also to interpreting  temporal trends in  eDNA detections within and between ecoregions, including better understanding the discrepancies between eDNA and specimen-based surveys results.

We

 will  present  a  new  DFO initiative  aiming to  develop an online tool to report and visualize trends in spatio-temporal eDNA distributions of Canadian species. The lat ter will fill important knowledge gaps on how genomic tools can differentiate impacted and non-impacted ecosystems associated with

human activities, such as aquaculture.