Estimating the biomass of fish stocks using novel genetic techniques

Abstract

Estimating the biomass and/or abundance (defined as the total weight and number of a species in defined space and time, respectively) of fish stocks is a crucial prerequisite for effective management. Various fishery‐dependent and ‐independent monitoring approaches are used to census populations; each with various advantages and limitations. In the last decade, there has been a focus on the potential to use traces of DNA left in the water to estimate not only the presence of a target species, but also their relative biomass and/or abundance. This method is appealing because it does not impact aquatic‐fauna welfare, and large numbers of sites can be quickly sampled—often more cost effectively than conventional methods. Nevertheless, like for all assessment methods, there are numerous abiotic and biotic factors affecting the strengths of relationships between eDNA concentrations and biomass and/or abundance.