Advantages and disadvantages of eDNA surveys for great crested newts: perceptions from practitioners

Note on a workshop held at Herpetofauna Workers Meeting, February 2017

Environmental DNA or eDNA, is DNA that is released into the environment (water, soil, faeces) by all living organisms, as they naturally shed cells as skin, hair, mucous, eggs and sperm, and decompose after death.  Recent advances in our ability to detect this DNA, by amplifying short fragments of the mitochondrial DNA which is present in all cells, have shown that it is now possible to detect freshwater species, including great crested newts,  just by testing water samples.

Large scale testing of this new technique by the Freshwater Habitats’ Trust in partnership with ARC, DICE and the technology company SpyGen, in 2013, demonstrated that it was possible to extend eDNA testing to successfully survey large numbers of ponds across England and Wales for great crested newts (Biggs et al., 2014). This was extended to commercial surveys in 2014, and since then thousands of eDNA samples have been collected and analysed by a wide range of laboratories.

Inevitably with such a rapid roll out of a new technology, there have been many questions about the technique, and some concerns have been expressed.  It was felt that these anecdotal comments should be collected,  and to this end Andrew Buxton (DICE) together with Gillian Benson and Paul Edgar (Natural England) and Kat Bruce (Nature Metrics) facilitated two workshops at the 2017 Herpetofauna Workers Meeting. These discussed  the pros and cons of using eDNA for commercial and voluntary great crested newt surveys.  This annual meeting, which is attended by over 200 commercial ecologists, volunteer recorders, scientists and statutory agency staff was felt to offer a good cross section of practitioners and decision makers, and would therefore provide some important indicators based on first hand personal experience in the field.

The paper by Andrew Buxton and Richard Griffiths reveals some of the key topic areas that were raised, and areas of concern identified, by the workshop participants. Practical suggestions about how to overcome these constraints were also presented, and will provide a basis for additional research in this area.

Citation

Buxton A.S. & Griffiths R.A. (2017) Advantages and disadvantages of eDNA surveys for great crested newts: perceptions from practitioners. Note on a workshop held at Herpetofauna Workers Meeting, February 2017. Unpublished

References:

Biggs, J., Ewald, N., Valentini, A., Gaboriaud, C., Griffiths, R., Foster, J., Wilkinson, J., Arnett, A., Williams, P. & F, D. (2014). Analytical and methodological development for improved surveillance of the great crested newt. Defra Project WC1067. Oxford.