North Somerset and Mendip Bats special area of Conservation (SAC)-Guidance on Development. Draft Supplementary Planning Document

Part A non-technical guidance

North Somerset and Mendip Bats Special Area of Conservation (SAC)



  1. Who is the guidance aimed at and why?

1.1     This advice is aimed at developers, consultants, and planners involved in planning and assessing development proposals in the landscapes surrounding the North Somerset and Mendip Bats SAC. 

1.2     The overall aim is for a clearer approach to considering impacts of development on the SAC. The guidance provides a consistent basis for understanding how rare horseshoe bats use the landscape and where there is likely to be greater risk or opportunity for development. This will help inform strategic planning for the area’s future housing needs.

1.3     The guidance will comprise a component of the development management process, to be considered in line with relevant policies, such as policy DM8 (Nature Conservation) of the adopted Development Management Policies of the North Somerset Local Plan; Policy D15 (Bat Consultation Zone) of the Revised Sedgemoor District Council Local Plan; Policy DP6 (Bat Protection Zone) of the Mendip District Council Local Plan; Policy DM2: Biodiversity and geodiversity of the Somerset County Council Minerals Plan; and Policy DM3: Impacts on the environment and local communities of the Somerset County Council Waste Core Strategy

1.4     At project level the guidance will help identify key issues at pre-application stage that can inform the location and sensitive design of development proposals and minimise delays and uncertainty.  Within the areas identified, there will be clear requirements for survey information and a strong emphasis on retaining and enhancing key habitat for bats and effective mitigation where required. This will demonstrate that development proposals avoid harm to the designated bat populations and support them where possible.

1.5     The guidance explains how development activities can impact the SAC and the steps required to avoid or mitigate any impacts. It applies to development proposals that could affect the SAC and trigger the requirements of the Habitats Regulations (see Annex 7).The local planning authority will consider, on the basis of evidence available, whether proposals (planning applications) are likely to impact on horseshoe bats and hence require screening for Habitats Regulations Assessment (HRA). Those are the proposals to which the guidance will be applied. This will reduce the likelihood that it would be applied to minor developments which would not have an impact on the SAC.

1.6     The guidance brings together best practice and learning from areas with similar approaches, such as Somerset County Council and South Hams, and the best scientific information available at the time of writing. It will be kept under review by North Somerset Council and Somerset County Council and their partners and is fully endorsed by Natural England. The planning guidance is part of a wider approach that is being pursued by partner organisations to safeguard and improve habitat for rare bats that includes farm management. The guidance is also consistent with Natural England’s Site Improvement Plan for the SAC.

  1. What is the Bats SAC?

2.1      Special Areas of Conservation (SAC) are European sites of international importance for wildlife. The Bat SAC is important for two bat species, Greater and Lesser Horseshoe bats. The SAC itself comprises component SSSIs which in North Somerset include, for example, the two maternity roosts at the Brockley Hall Stables SSSI and King’s Wood SSSI, and also hibernation roosts like the Banwell Bone Caves and, in Somerset, the maternity and hibernation roosts in the Cheddar Complex SSSI and the hibernation roosts at Wookey Hole SSSI. 

2.2      However the landscapes around the SAC itself are also important in providing foraging habitat needed to maintain the favourable conservation status of the horseshoe bats. Therefore the guidance sets out strong requirements for consultation, survey information and appropriate mitigation, to demonstrate that development proposals will not adversely impact on the designated bat populations.

  1. Juvenile Sustenance Zones

3.1      The guidance identifies the Juvenile Sustenance Zones of 1 kilometre (km) around the maternity roosts.

3.2      New build development on green field sites should be avoided in the Juvenile Sustenance Zones (JSZs) in view of their sensitivity and importance as suitable habitat as foraging areas for young bats, being within 1km of maternity roosts for Greater Horseshoe bats and 600 metres for Lesser Horseshoe bats. 

  1. Bat Consultation Zone

4.1      The guidance also identifies the “Bat Consultation Zone” where horseshoe bats may be found, divided into bands A, B and C, reflecting the likely importance of the habitat for the bats and proximity to maternity and other roosts.  

4.2     Within the Consultation Zone development is likely to be subject to particular requirements, depending on the sensitivity of the site.

  1. Need for early consultation

5.1     Section 3 of Part B of the guidance stresses the need for pre-application consultation for development proposals.

5.2     Within bands A or B of the Consultation Zone, proposals with the potential to affect features important to bats (identified in Section B paragraph 3.2 below) should be discussed with the local authority and/or Natural England as necessary.

5.3     Within band C developers should take advice from their consultant ecologist.   

  1. Survey requirements

6.1     Section 3 of Part B and Annex 3 of the guidance sets out the survey requirements normally applying to development proposals within the Bat Consultation Zone. Outside the Bat Consultation Zone development proposals may still have impacts on bats, and developers should have regard to best practice guidelines, such as Bat Conservation Trust survey guidelines and Natural England's Standing Advice for Bats. North Somerset Council has also produced a Bat Survey Requirements leaflet.

6.2     For proposals within the Consultation Zone (all Bands), developers must employ a consultant ecologist at an early stage to identify and assess any impacts.

6.3     For proposals within bands A and B of the Bat Consultation Zone, full season surveys will be needed (unless minor impacts can be demonstrated), and must include automated bat detector surveys. Survey results are crucial for understanding how bats use the site, and therefore how impacts on horseshoe bats can be avoided, minimised or mitigated.  Where mitigation is needed the survey results will inform the metric for calculating the amount of habitat needed (see Annex 5).

6.4     Within band C survey effort required will depend on whether a commuting structure is present and the suitability of the adjacent habitat to support prey species hunted by horseshoe bats.

  1. Proposed developments with minor impacts

7.1     In some circumstances a developer may be able to clearly demonstrate (from their qualified ecologist’s site visit and report)  that the impacts of a proposed development are proven to be minor and can be avoided or mitigated (or do not require mitigation) without an impact on SAC bat habitat, so a full season’s survey is not needed. This should be substantiated in a suitably robust statement submitted as part of the development proposals.

  1. Need for mitigation, possibly including provision of replacement habitat

8.1     Within the Bat Consultation Zone (all Bands), where SAC bats could be adversely affected by development appropriate mitigation will be required.

8.2     Development proposals should seek to retain and enhance existing habitats and / or features of value to bats such as those listed in paragraph 3.2 of Part B in this guidance. Where this is not, or is only partially possible appropriate mitigation such as the provision of replacement habitat will be required. The council’s ecologist will have regard to relevant considerations in determining the mitigation requirements, including survey results and calculations relating to quantity of replacement habitat. Annex 5 sets out the methodology and metric for calculating how much replacement habitat should be provided[1].

8.3     Any replacement habitat must be accessible to the horseshoe bat population affected.

8.4     Where the replacement provision is to be made on land off-site (outside the red line development boundary for the planning application) any existing value of that land as bat habitat will also have to be factored in to the calculation.

8.5     Where the replacement provision is to be off site, and land in a different ownership is involved, legal agreements are likely to be needed to ensure that the mitigation is secured in perpetuity. 

8.6     An Ecological Management Plan for the site must be provided setting out how the site will be managed for SAC bats in perpetuity.

8.7     Where appropriate a Monitoring Strategy must also be provided to ensure continued use of the site by SAC bats, and include measures to rectify the situation if negative results occur. 


[1] In the Somerset County area developers may ask the Local Planning Authority to carry out the calculation for the amount of habitat required to replace the value of that lost to horseshoe bats prior to the application being submitted, to check that the proposed master plan for the site has adequate land dedicated to the purpose.  A charge may be levied for this service.