Telephone: 0141 342 5404

The Elusive Great Crested Newt: Tracking It Down With eDNA Surveys

As Great Crested Newts (GCN) return to waterbodies each spring to breed, this is the ideal time to check for their presence within a site. One of the ways in which we can do this is using environmental DNA (eDNA).

Following a study undertaken by DEFRA, the use of eDNA has been accepted by Natural England as an appropriate method of determining presence or absence of GCN within a water body. Scottish Natural Heritage also accepts this method.

MacArthur Green offers a licensed surveyor who has been trained in Natural England’s approved survey protocol to undertake the eDNA surveys. The technique can reduce survey requirements to only one visit to a waterbody in order to determine presence of GCN. By offering this service in line with current industry guidelines, we provide our clients with accurate results in shorter time period than that associated with conventional survey methods.

Where no presence of GCN is detected, this means a reduced cost to the client as no further survey is necessary. It also means a reduction in the disturbance to the water body and species present within it.

Water samples to inform the eDNA surveys must be collected between mid-April and 30th June, in order to confirm presence or absence in line with accepted protocol. Surveys conducted outwith this survey window cannot be used to confirm absence of GCN. The kits used to collect the samples must be ordered from an approved lab in advance of the surveys taking place, so this should be kept in mind for project planning.

Where the presence of GCN is confirmed and there remains a requirement to determine the population size; surveys using conventional methods are necessary. These include bottle trapping, netting, torching and egg searches. MacArthur Green staff are experienced in undertaking such surveys and estimating population size. In terms of project planning, it is important for clients to note that surveys may have to be conducted the following year depending on when the eDNA surveys were carried out, and when survey results are received back from the labs.

MacArthur Green provides the following services:

  • Initial site assessment of water bodies and terrestrial habitat and calculation of Habitat Suitability Index (HSI) to determine the habitat suitability for GCN.
  • eDNA surveys conducted by a licensed surveyor who has been trained in Natural England’s approved survey protocol.
  • Conventional survey methods, such as bottle trapping, netting, torching and egg searches, and estimations of population size where presence of GCN is confirmed.
  • Habitat enhancement and design of new habitat, e.g. new breeding ponds, hibernacula, etc.
  • Translocation of GCN, including pitfall trapping.

Please call on 0141 342 5404 to discuss any GCN questions you may have.