What is eDNA?
eDNA, or environmental DNA is genetic material given off by an organism into its environment. In the case of great crested newts, the eDNA samples are collected from bodies of water. The newt DNA is released into the water via shed skin cells, mucus, sperm, eggs, faeces and decomposing animals. Studies suggest that both the larval stage and adult stages are detectible using eDNA analysis (Rees et al, 2017; Buxton et al, 2017).
This DNA given off into the water can persist for a number of weeks, allowing us to test for its presence in water samples.
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.
Are you able to detect multiple species?
At the moment our test only detects Great Crested Newts.
Are you able to estimate GCN population size using eDNA analysis?
No. At this time eDNA analysis can only generate presence/absence results.
Do I need a GCN licence to survey?
A licensed great crested newt surveyor must collect the sample if the eDNA test is in support of a license application.
When can samples be taken?
Natural England accepts eDNA survey results from samples collected between 15 April and 30 June each year.
Do you perform out of season eDNA testing?
We can perform testing year round.