How accurate is eDNA testing?

Natural England’s eDNA protocol has proved to be a rapid and effective way to test for the presence/absence of great crested newts.

Biggs et al. (2015) showed that when newts were present, eDNA was 99.3% effective at detecting newts in ponds where they were known to occur. No false positive were reported for this study and 8.7% of sites had false negative (newts were present but not detected) results. This compares to detection efficacy of 76% for bottle trapping, 75% for torch surveys and 44% for egg searches.

Biggs et al. (2015) Using eDNA to develop a national citizen science-based monitoring programme for the great crested newt (Triturus cristatus). Biological Conservation 183 (2015) 19–28.