Great Crested Newt
Habitat Suitability Index (HSI Surveys)
Habitat Suitability Index Assessments (HSI Surveys) measures the suitability of a pond to establish the likelihood of Great Crested Newts (GCN) being present.
The assessment is based on ten factors including pond area, shade, terrestrial habitat and water quality.
These surveys can be undertaken all year round, although where possible they should be done during March – June which is GCN peak breeding season.
HSI Assessments often form part of PEA surveys and will ideally include ponds within 500 m of the development where access can be granted. This helps assess the likelihood of GCN being found within the site itself.
If ponds are found to be suitable for great crested newts, eDNA or traditional surveys may be required, depending on the extent of impact.
eDNA Surveys
eDNA surveys involve taking water samples from the pond which are sent for analysis to check for the presence of great crested newt DNA within a pond. This can then confirm if GCN are utilising the pond during the breeding season.
eDNA can prove a cost-effective method, particularly where a large number of ponds are present as it can confirm likely absence of great crested newts without the need for numerous site visits.
eDNA surveys can only be carried out between 15th April – 30th June as this is the peak breeding season. Ideally, they should be carried out as early as possible during this time period to prevent delays should follow up surveys being required.
If the presence of great crested newts has been confirmed and an impact cannot be avoided, traditional survey methods and a Natural England Licence may be required.
Tom Haley Ecology will be able to assist on the requirements on a project by project biases
Traditional Surveys
Traditional presence/absence surveys involve a range of survey techniques including torchlight searching, bottle trapping, netting, egg searching and refugia checks. A minimum of three techniques will be used on each survey.
Between 4 and 6 surveys will be required between Mid-March and June with at least half of the surveys occurring between mid-April and mid-May.
If presence of great crested newts has been confirmed and an impact cannot be avoided a Natural England Licence may be required.
Tom Haley Ecology will be able to assist on the requirements on a project by project biases.
