Great Crested Newts Survey

If there are ponds or other aquatic features within or near a site, great crested newts will need further assessment.

EBD Expertise:

We are experienced in undertaking small to large-scale GCN surveys and delivering complex mitigation projects including translocations. Using our years’ of experience, we will carry out the necessary scoping surveys on your site to determine the best options for further survey work to determine presence or likely absence of this species on your site; and provide pragmatic options for licensing and mitigation where the presence of GCN requires consideration.

Why and when do you need a great crested newt survey?

If you are planning a development project that is at risk of disturbing or damaging great crested newts (GCN) and their habitat, you will need to appoint an ecologist to assess the potential impacts of the proposals. This may entail a traditional assessment (conducting a GCN habitat scoping assessment and survey to determine the likely presence of this species within your site) or assuming presence and registering the site under a District Licence. We have published a blog which compares these two approaches. Here we explain what the traditional assessment process entails.

Great crested newts are protected by law as within Europe, the population has suffered significant declines in range and abundance and within the UK we support a large proportion of the declining population. The population is declining largely due to a loss of ponds and suitable habitat.

The usual ‘trigger’ for a GCN survey requirement is a request from your planning consultant, architect or the local planning authority so that a report can be submitted with a planning application. GCN surveys may also be recommended as the result of an ecological scoping survey or preliminary ecological appraisal.

What does a GCN survey entail?

There are generally three stages to a traditional survey for GCN. The first stage includes an assessment of all ponds within 500m of your site. The assessment, known as a habitat suitability index (HSI) takes into account ten variables such as pond size, shading and vegetation present to calculate a score/ category for the likelihood of the pond supporting newts.

Taking into account your site, the pond HSI scores and habitats between them we then determine if a full GCN survey is required based on the likelihood of your work having an impact on GCN.

A full GCN survey can be very intensive and involves surveying a pond on between four and six occasions using different techniques (egg-searches, bottle-traps, torching and nets) to determine the presence or likely absence of newts. These surveys are constrained by the season and can only be conducted between mid-March and mid-June with at least half of the visits between mid-April and mid-May. If newts are identified in any of the first four visits then full six visits are required to determine the population size class which would be needed to inform a licence application.

Alternatively, presence/absence can be determined through a technique called environmental DNA (eDNA) which involves taking water samples from ponds and analysing the sample for the presence of newt DNA. This is much cheaper than a full survey but if newts are present a full survey (above) is then still required. The eDNA survey is also restricted to the period from mid-April to the end of June.

GCN Survey Timing

Habitat suitability surveys for GCN can be undertaken throughout the year, although are more effective in the summer months when an accurate assessment of vegetation cover can be undertaken.

Full Presence / absence surveys should be carried out between mid-March and mid-June, with half of the surveys undertaken between mid-April and mid-May; and eDNA presence/absence surveys can be carried out from mid-April until the end of June.

If you miss these survey windows and you planning application needs to progress quickly it may be appropriate to assume presence of GCN and register the site under a District Licence. More information on the two approaches can be found on our blog post here.