Evaluation of the detection of fish and amphibians using environmental DNA techniques in central Chile: implications for environmental monitoring

Abstract

Environmental DNA (eDNA) detection is a non-invasive molecular method proposed as an alternative to conventional field techniques for biodiversity sampling. In this study we compared the eDNA technique with conventional methods for detecting fish and amphibians in three streams of the Aconcagua River basin (El Gallo, El Sauce, and El Melón streams). Using eDNA we identified a total of six fish species and four amphibian species, with results consistent with conventional method records. However, some discrepancies were observed. For instance, the species Rhinella arunco and Pleurodema thaul in El Sauce stream were only detected through conventional methods. These findings highlight the utility of eDNA in biodiversity studies, particularly for detecting low-abundance or elusive species, though it appears less effective for amphibians with temporally restricted aquatic life stages.