eDNA is DNA that is collected from a range of environmental samples including soil and water rather than being directly sampled from a plant or animal. All organisms leave traces of their DNA as part of their normal existence. Sources of eDNA include, faeces, mucus, gametes, skin, carcasses and hair.
The collection of eDNA offers great potential for monitoring species, both common ones and those which require efforts to preserve their existence.
Recent examples where the use of eDNA has proved invaluable include tracking tropical shark activity in the greater Caribbean, monitoring the near extinct European weather loach in Denmark and of course identifying the presence of Great Crested Newt in the UK.
eDNA analysis offers an alternative to traditional GCN survey methods that require multiple site visits at times defined by the specific method being used. eDNA analysis can provide a presence/absence result after just a single site sampling visit. Water samples collected are sent to Cellmark’s laboratories for testing using the protocol recommended by Natural England.
At present eDNA testing cannot be used for determining GCN population sizes.