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Environmental DNA (eDNA) testing is a recognised survey technique for establishing the presence or absence of great crested newts in ponds during the breeding season. Using eDNA sampling has many advantages for projects, including fast turnaround times and potentially eliminating the need for further surveys – both factors which have beneficial cost implications for projects.

Great Crested Newts (like this one picture) are European Protected Species. Image by Senior Ecologist, Matt Cook

Great Crested Newts (like this one pictured) are European Protected Species. Image by Senior Ecologist, Matt Cook

Advantages of eDNA Sampling

eDNA sampling has a number of advantages over more traditional methods of surveying for great crested newts, allowing samples to be collected up until 30th June. The protocol requires only one daytime visit by a licenced ecologist during the newt breeding season to determine presence or absence. This means that eDNA sampling has the potential to reduce the level of survey effort needed in comparison to conventional methods, which require a minimum of four survey visits, each including evening and morning survey, between April and June.

There are a number of scenarios where this technique can benefit projects, including:

  • As a cost effective way of scoping future survey requirements (i.e. population size class assessment surveys) for projects where there is sufficient time available to carry out the detailed conventional survey the following year.
  • To confirm absence in ponds that are considered to have low potential to support great crested newts but where further confirmation is required.
  • For ponds with high potential to support great crested newts, and where a key part of the conventional survey period (mid-April to mid-May) has been missed, but where there is still time available to collect eDNA samples (before 30th June). In this situation, an eDNA finding of “absence” would avoid the need for further conventional presence/absence survey.

eDNA Sampling

Great crested newt DNA is released into aquatic environments through shed skin cells, urine, faeces and saliva. The trace DNA can persist in water for several weeks and collected using the detailed sampling and analysis protocol that has been devised (samples should be collected between 15th April and 30th June). Samples are then sent to a recognised laboratory for analysis. The highly sensitive laboratory testing is based on qPCR, allowing detection of great crested newt presence or absence.

Laboratory testing is conducted by our partner NatureMetrics, a highly experienced company who have conducted GCN eDNA analysis since 2015. NatureMetrics follow Natural England’s approved protocol (WC1067), which ensures that the test meets regulatory requirements. As industry leaders, NatureMetrics provide a quality service, and scored 100% in the 2018 proficiency test.

Testing turnaround times can be suited to the project’s needs. Options include Standard Turnaround (10 working days from receipt of sample in the lab) and Fast Turnaround service (5 working days from receipt). Super-fast turnaround (2 days) is also usually available on request.

Baker Consultants has extensive experience in great crested survey and mitigation, including major infrastructure project work involving thousands of newts and complex EPS licensing. We have numerous licenced great newt surveyors and we have undertaken eDNA survey work since in 2015.

 

At Baker Consultants, our terrestrial ecologists are fully licensed and experienced great crested newt surveyors and have carried out accredited training in environmental DNA (eDNA) field sampling, led by Dr Jeremy Biggs, Director of the Freshwater Habitats Trust (FHT).

This innovative and recently developed survey method is used to detect microscopic fragments of DNA biomarkers belonging to great crested newts, which persist in waterbodies for between 1 and 3 weeks, depending on environmental conditions. This method can be used to determine species occupancy in ponds (i.e. presence/absence) and has the potential advantage of increasing survey efficiency from a financial, time and labour intensity perspective.

eDNA service at Baker Consultants

eDNA service at Baker Consultants

The fact that eDNA persists in waterbodies (excluding sedimentary deposits) for a relatively short period of time, means that collected samples should contain the DNA fragments of great crested newts that were recently present within the waterbody. This technique has been supported by Natural England and where negative results are returned following analysis, the requirement for further surveying using the standard bottle trapping, egg search and torchlight methods can be omitted; thus potentially saving the client time and money. Furthermore, a recent study published by DEFRA (Department for Environment, Food and Rural Affairs) and conducted by the FHT, showed that eDNA sampling used to determine the presence of great crested newts had an accuracy level of 99.3%, compared to only 76% via the standard bottle trapping technique.

However, to support a licence application for development, Natural England will only accept the results of this new sampling technique if an appropriately trained and experienced great crested newt surveyor collects the samples. Additionally, in order to be accepted, these samples must be collected between 15th April and 30th June.

Baker Consultants are able to provide this eDNA service on request. Further details on prices and availability will be released in the near future. If you have any queries regarding this service, please contact Jake Robinson.