Data from: Estimating fish population abundance by integrating quantitative data on environmental DNA and hydrodynamic modeling

Molecular analysis of DNA left in the environment, known as environmental
DNA (eDNA), has proven to be a powerful and cost-effective approach to
infer occurrence of species. Nonetheless, relating measurements of eDNA
concentration to population abundance remains difficult because detailed
knowledge on the processes that govern spatial and temporal distribution
of eDNA should be integrated to reconstruct the underlying distribution
and abundance of a target species. In this study, we propose a general
framework of abundance estimation for aquatic systems on the basis of
spatially replicated measurements of eDNA. The proposed method explicitly
accounts for production, transport, and degradation of eDNA by utilizing
numerical hydrodynamic models that can simulate the distribution of eDNA
concentrations within an aquatic area. It turns out that, under certain
assumptions, population abundance can be estimated via a Bayesian
inference of a generalized linear model. Application to a Japanese jack
mackerel (Trachurus japonicus) population in Maizuru Bay revealed that the
proposed method gives an estimate of population abundance comparable to
that of a quantitative echo sounder method. Furthermore, the method
successfully identified a source of exogenous input of eDNA (a fish
market), which may render a quantitative application of eDNA difficult to
interpret unless its effect is taken into account. These findings indicate
the ability of eDNA to reliably reflect population abundance of aquatic
macroorganisms; when the “ecology of eDNA” is adequately accounted for,
population abundance can be quantified on the basis of measurements of
eDNA concentration.