Bat survey

Bat surveys will need to be undertaken by a qualified ecologist and have to date from within the previous two years, otherwise your application will be considered invalid.

Because bats are a protected species under the Wildlife and Countryside Act 1981, a bat survey is required under the below conditions.

  • All development, including demolition, within the Juvenile Sustenance Zone (North Somerset) as set out within the North Somerset and Mendip Bats Special Area of Conservation (SAC) Guidance on Development: Supplementary Planning Document (adopted January 2018).
  • All development, including demolition, but excluding change of use and householder development, within Bat Consultations Zones A and B as set out within the North Somerset and Mendip Bats Special Area of Conservation (SAC) Guidance on Development: Supplementary Planning Document (adopted January 2018).
  • Development that affects existing weatherboarding, hanging tiles or pitched roofs (excluding roofs covered with prefabricated steel or sheet materials, or roof voids that have been converted to living space), on any building within Bat Consultations Zone A as set out within the North Somerset and Mendip Bats Special Area of Conservation (SAC) Guidance on Development: Supplementary Planning Document (adopted January 2018).
  • Alterations to an existing agricultural or equestrian building with externally exposed brick, stone or a wood framed roof
  • Development affecting underground structures, brick or stone built industrial sites or bridge structures
  • Alteration works to any building or structure where bat roosts are known or previously recorded to be present.
  • Floodlighting of any building meeting criteria 1 or churches, listed buildings or green space (e.g. sports pitches) within 50m of woodland, water, field hedgerows or tree lines with connectivity to woodland and water
  • Felling or removal of mature trees that have a significant amount of:
    • complex growth form
    • natural cavities (often present in beech, oak, ash)
    • loose bark or ivy cover
    • damaged caused by rot/lighting/wind/woodpeckers’
    • felling or removal of woodland of 0.5 hectares or more
    • removal of hedgerows or tree lines connected to woodland or a significant body of fresh water.

Notwithstanding the above criteria, a full bat survey and report is NOT required if an initial bat survey (Scoping Survey, Preliminary Ecological Appraisal (PEA) or an Extended Phase 1 Habitat Survey) is submitted with the application. It will need to confirm that the building is unlikely to support bats and that bats are unlikely to be adversely impacted.

If an initial bat survey (Scoping Survey, Preliminary Ecological Appraisal (PEA) or an Extended Phase 1 Habitat Survey) is submitted with the application that confirms that further surveys for bats (Emergence/Re-entry or Activity Surveys) are required, the application will not be valid unless the required survey is carried out in full and a report of the findings are submitted with the application.

Applications submitted with surveys which are out of date will not normally be considered valid.

When a survey is not required

You will only need to undertake a survey if there is a “reasonable likelihood’ of bats being present.

A bat survey is not normally required for: 

  • dwellings where the works would affect a small roof void of a pitched roof (less than 5 cubic metres) or densely cluttered with storage items that restrict available flying space
  • buildings that have had an initial bat survey (Scoping Survey, Preliminary Ecological Appraisal (PEA) or an Extended Phase 1 Habitat Survey) that confirms that the building is unlikely to support bats and that bats are unlikely to be adversely impacted

However, if an initial bat survey (Scoping Survey, Preliminary Ecological Appraisal (PEA) or an Extended Phase 1 Habitat Survey) is submitted with the application that confirms that further surveys for bats (Emergence/Re-entry or Activity Surveys) are required, the application will not be valid unless the required survey is carried out in full and a report of the findings are submitted with the application.

More information

Bat surveys are based on the following additional policy and guidelines: