Great Crested Newt Surveys

When developing or demolishing a site where the presence of Great Crested newts is a possibility, you may need a Great Crested newt survey to ensure a successful planning application. Our skilled team of ecologists take away the hassle involved by providing the surveys and reports you need in order to move forward with your project while keeping the conservation of this protected species at the forefront.

Where do Great Crested Newts live?

Contrary to common belief, Great Crested newts spend most of their life cycles on land. Whilst on land, Great Crested newts will either be foraging or seeking refuge above (in piles of deadwood or rubble, for example) or below ground. During weather “extremes”, for example, such as during dry periods in the summer or lengthy cold periods in the winter, Great Crested newts remain underground in crevices or within hibernacula above ground.

Adult Great Crested newts will move from their overwintering sites to breeding sites (ponds) between February and April, weather dependent. Breeding adults will normally leave breeding ponds between late May and July. Great Crested newt presence/likely absence surveys are therefore undertaken between mid-March to June when Great Crested newts are actively breeding in ponds.

Why are Great Crested Newts protected?

Like much of our British wildlife, Great Crested newts faced a population decline due to agricultural intensification in the late twentieth century. This was because much of the countryside was turned over for agriculture, and changes to farming practices meant that ponds were infilled as they became superfluous to requirements for farming. In addition to this, chemical spraying and ploughing around ponds made the habitat adjacent to ponds increasingly inhospitable.

Great Crested newts are highly sensitive to changes to their habitats, including pollution and agricultural intensification, therefore declining more severely than other newt species.

Since becoming a protected species, Great Crested newts are benefiting from the protection afforded to them and are becoming more widespread across the UK. Populations of Great Crested newts have declined dramatically across Europe and therefore, Great Crested newts in the UK have become an important population for the conservation of the species internationally.

HSI Assessments

The Habitat Suitability Index (HSI) assessment is a scoring system developed to assess ponds and other water bodies based on ten suitability indices, each of which relates to the habitat’s suitability to support great crested newts.

HSI assessments are used in the first instance to assess a pond’s suitability to support Great Crested newts. Based on this initial assessment, further Great Crested newt presence/likely absence surveys may be required.

HSI assessments can be carried out as a part of a Preliminary Ecological Appraisal or may be recommended following the Preliminary Ecological Appraisal if access needs to be organised to visit a pond outside of the site boundary. HSI assessments can be undertaken at any time of year.

Presence/Likely Absence Surveys

These are ‘traditional’ surveys and involve a total of four pond surveys by a licensed surveyor using various methods to determine whether Great Crested newts are present or likely to be absent from the pond. Surveys can be undertaken between mid-March and June and at least two surveys need to be completed between mid-April and mid-May (Please refer to our Ecology Survey Calendar for further information on GCN and other protected species surveys.). If Great Crested newts are found, a further two surveys will be required to determine the population size class.

During the Great Crested newt presence/likely absence surveys, licensed surveyors will also undertake an egg search. Great Crested newts lay a single egg on soft, foldable vegetation (for example, water forget-me-not leaves). Finding a Great Crested newt egg is a fast and simple way of confirming a Great Crested newt’s presence in a pond. If one Great Crested newt egg is found, no further egg searches will be undertaken at that pond to preserve any remaining eggs.

Population Size Class Assessments

Population size class assessments involve six surveys using the same methods as presence/likely absence surveys and are only undertaken once Great Crested newts have been identified. This is done in order to determine the population size class that the population of Great Crested newts in the pond falls into (low, medium, or large). At least three surveys must be undertaken within the optimum period of mid-April to mid-May. (Please refer to our Ecology Survey Calendar).

Environmental DNA (eDNA) Testing

Environmental DNA testing involves a licensed person taking water samples from the pond(s), which are subsequently sent off for analysis at a laboratory to determine whether great crested newt DNA is present or absent. eDNA testing can be carried out between mid-April and the end of June (Please refer to our Ecology Survey Calendar) which leaves a short period of time within the survey window to assess population sizes if Great Crested newts are found. Consequently, eDNA is not suitable for all projects. However, eDNA surveys are suitable for:

• Large projects with long lead times: they can be undertaken a year in advance to scope in or out, large numbers of waterbodies with potentially considerable savings to the developer.

• Temporary and low-impact developments that may only require presence or absence surveys.

• Small projects with limited risk of Great Crested newt presence.