A framework for estimating the sensitivity of eDNA surveys

Area of Science:

• Ecology
• Environmental Science
• Molecular Biology

Background:

• All survey methods exhibit imperfect sensitivity, necessitating careful interpretation of results.
• Environmental DNA (eDNA) detection is increasingly used for inferring species distributions.
• The sensitivity of eDNA techniques requires thorough evaluation for accurate ecological assessments.

Purpose of the Study:

• To develop and present a model for estimating target DNA concentration and dispersion at survey sites.
• To quantify the sensitivity of environmental DNA (eDNA) survey methods.
• To optimize sampling schemes for achieving high detection probabilities in eDNA surveys.

Main Methods:

• A novel model was developed to estimate target DNA concentration and dispersion.
• The model was applied to eDNA survey data for Oriental weatherloach (Misgurnus anguillicaudatus).
• Sensitivity was assessed based on varying DNA molecule concentrations and sampling strategies.

Main Results:

• DNA molecule concentration varied spatially and temporally, being higher in spring at two sites.
• The eDNA survey method demonstrated ≥95% sensitivity at DNA concentrations of ≥11 molecules per litre.
• The study provides a framework for comparing sampling schemes to achieve desired sensitivity levels.

Conclusions:

• The developed model allows for the quantification of eDNA survey sensitivity.
• Researchers can optimize eDNA survey designs to enhance target species detection probability.
• The findings facilitate spatial and temporal comparisons of DNA concentrations for ecological monitoring.