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.

  1. 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).
  2. All development, including demolition, which is located 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) except for:
    • proposals for a change of use only or;
    • householder development within Bat Consultation Zone B that is within the settlement limits of Weston-super-Mare, Clevedon, Yatton, Nailsea or Portishead, and where the proposal does not involve the demolition of a building, or will not break into or impede bat access to any roof space.
  3. Development, including demolition, that affects agricultural buildings with traditional brick or stone construction or with exposed wooden beams.
  4. Development, including demolition, that affects:
    • weatherboarding;
    • hanging tiles;
    • pitched roofs (excluding roofs covered with prefabricated steel or sheet materials, or roof voids that have been converted to living space);
    • and which is on a building within 200m of woodland or fresh water.
  5. Development, including demolition, that affects:
    • buildings erected before 1914 with gable ends or slate roof;
    • buildings erected before 1914 which are within 400m of woodland or a body of fresh water (including water courses);
    • buildings erected between 1914 and 1960 which are within 200m of woodland or a body of fresh water (including water courses).
  6. Development affecting underground structures, brick or stone built industrial sites or bridge structures unless the structure:
    • is in a heavily urbanised area affected by artificial light
    • is heavily disturbed, for example if people use it regularly
    • is small and draughty
    • has smooth surfaces (bats cannot grip on polished surfaces)
  7. Alteration works to any building or structure where bat roosts are known or previously recorded to be present.
  8. Floodlighting within 50m of woodland, fresh water (including water courses), field hedgerows or tree lines with connectivity to woodland and fresh water.
  9. Felling or removal of trees that are 20cm or more in diameter at 1.5 metres and which have a significant amount of:
    • complex growth form
    • natural cavities (often present in beech, oak, ash)
    • loose bark
    • ivy cover
    • damaged caused by rot/lighting/wind/woodpeckers
  10. Felling or removal of woodland of 0.5 hectares or more.
  11. Removal of hedgerows or tree lines connected to woodland or a body of fresh water (including water courses).

Notwithstanding the above, a full bat survey is not required if a suitably qualified ecologist confirms in writing that a bat survey is not required, together with an explanation of the reasons why.

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.

Once an application is received and registered, if the case officer finds that there is a reasonable likelihood of bats being present, they will request a bat survey, even if it is not required by any of the criteria listed above – if a suitable survey is not submitted when requested then it is likely the permission will be refused.

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

When a survey is not required

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: