Estimating fish population abundance by integrating quantitative data on environmental DNA and hydrodynamic modelling

We propose a general framework of abundance estimation based on spatially replicated quantitative measurements of environmental DNA in which production, transport, and degradation of DNA are explicitly accounted for. Application to a Japanese jack mackerel ( Trachurus japonicus ) population in Maizuru Bay revealed that the method gives an estimate of population abundance comparable to that of a quantitative echo sounder method. These findings indicate the ability of environmental DNA to reliably reflect population abundance of aquatic macroorganisms and may offer a new avenue for population monitoring based on the fast, cost-effective, and non-invasive sampling of genetic information.