A complimentary approach to Atlantic Cod stock assessment on the Faroe Bank using environmental DNA samples.

The overall objective of the project is to develop and validate an eDNA sampling and analysis protocol for the detection and quantification of Atlantic Cod biomass on the Faroe Bank. The end goal is to better understand of the spatial and temporal distribution of cod biomass on the Faroe bank to directly address recent management policies for closing the fishery. In order to achieve this goal three specific project aims have been identified:
1. Develop a qPCR-eDNA assay for Atlantic Cod
2. Compare eDNA concentrations with biomass estimates from ground-fish surveys on the Faroese Shelf
3. Measure eDNA concentrations in water samples from the Faroe Bank.

Marine organisms leave behind traces of their DNA in aquatic environments from a range of processes. The objective of this project was to compare the concentration of environmental DNA originating from Atlantic cod with their biomass determined from trawl surveys.

During the project new methods were set up to isolate and quantify DNA originating from Atlantic cod in seawater samples using quantitative PCR. A comparison of this new technique with demersal trawl biomass was conducted around the Faroe Islands. The results reveal that there is a good correlation between the biomass of cod and concentration of DNA in seawater samples. This highlights the possibility to examine the spatial distribution of commercially important fish species in marine systems from chemical signatures in seawater.