Fig. 3

While low abundance eDNA is stable for a month when stored on silica-desiccated filters at all temperatures, storage up to a year is most stable at − 20 °C. A “standard” slurry was prepared to emulate a typical eDNA water sample which was filtered and the filters subsequently stored under silica desiccation at the indicated temperatures for 1 week (1 W), 1 month (1 M), 5 months (5 M) and 12 months (12 M) (n = 5 per temperature and time point; see Additional file 1: Figure S1 for details). The data are plotted as median starting copies per reaction (black line) for the A eFrog3 and B eLICA1 assays with median absolute deviations (error bar). Individual data points for each filter replicate are shown as open circles. Significant pairwise comparisons with 1 week, 1 month, and 5 months (Wilcoxon p = 0.06) are denoted by lowercase a, b and c, respectively. A black bar above a temperature group represents significance at p = 0.05 (Friedman) within the group