What is a Bat Survey and Why Might I Need One?

Have you ever been told by a planning authority or perhaps a planning consultant or may be an architect that you need a bat survey? If the answer to this question is yes, then it is possible this request was made in support of a proposed or consented development. Alternatively, it could also have been made in support of a project or task that doesn’t require planning consent, for example, building works or repairs.

For the non-ecologist, being told you might need a bat survey might come as a bit of a surprise or perhaps even sound a little over-the-top. Flabbergasted? Well, don’t be... We’ve written this blog to help you understand why bats are important and what to expect from a bat survey.

Bat populations in the UK have declined so significantly in recent decades that some species are now considered to be threatened and endangered. This is the main reason why the protection afforded to bats is some of the strictest in the UK. So are some of the penalties, if you happen to break the law. Accounting for differences between England, Scotland and Northern Ireland, it is an offence to deliberately and/or recklessly disturb, capture, injure or kill a wild bat. It is also an offence to deliberately and/or recklessly disturb, destroy and/or obstruct access to a bat roost, which is a structure or place bats use for shelter or protection, even if such places are not in active use by bats. Penalties can include unlimited fines and/or custodial sentences of up to six months in prison.

Good practice guidelines, as published by the Bat Conservation Trust (BCT), outlines survey methods and survey effort required in order to establish the presence of roosting bats and determine how proposed development and/or other activities could impact upon bat populations. The latest version of the guidelines includes improvements to good practice within a number of key areas. These revisions are now being actively adopted throughout the industry as part of the application of good ecological practice. A copy of the guidelines can be obtained via the following this link.

Where a survey has been requested in support of a planning application, be it lodged or proposed, then it is the responsibility of the applicant to organise and pay for the survey. Alternatively, if the applicant has an agent, for example, an architect or project manager, then it may be possible to arrange and pay for a survey through them. For everyone else, it is typically the responsibility of the person undertaking and/or instructing the work to organise and pay for the survey, for example, homeowner or business.

When planning the need for a bat survey, it is necessary to determine two important factors. Firstly, is there a reasonable chance of bats being present? Secondly, if present, could bats be affected by the works that are proposed, whether it is a large development or small-scale project or even a minor repair, for example, works to the roof of your home. Given the protection afforded to bats and their roosts, it is always best to contact a professional licensed ecologist or consultant for advice and support in this regard. When determining the need for a survey, a licensed ecologist will consider the scale and characteristics of the development, project or task, in addition to the suitability of existing structures and surrounding landscape for bats. They will also take into account pre-existing records obtained through consultation with third-party organisations, for example, biological record centres. Typically, these considerations form part of an initial assessment, often referred to as a preliminary roost assessment, which forms part of an over-arching bat roost inspection survey.

In line with the BCT’s good practice guidelines, bat survey effort, including preliminary roost assessments, should be undertaken by a licensed bat ecologist or by experienced ecologists working under the direct supervision of a licensed bat ecologist. A licensed bat ecologist holds a personal licence from one of the UK’s non-department public bodies, for example, NatureScot. In general terms, the licence permits the licence holder to catch and handle bats for identification purposes and/or to enter a roost to gain more information about the roost or its occupants. A general internet search is the most effective method of finding a licensed bat ecologist or as they are sometimes referred to, a licensed bat worker. Try using search phrases such as ‘I need a bat survey’ or ‘I need a licensed bat ecologist or bat worker’ followed by the general area in question, for example, a city, town or administrative area. When choosing a licensed bat ecologist, it is also important to ensure they hold an appropriate professional membership, for example, membership to a chartered society or institute.

Following completion of a preliminary roost assessment, your licensed bat ecologist will advise you further on the need for additional investigation and/or survey effort, for example, hibernation survey, ground-level tree assessment, aerial inspection survey, presence/ absence survey, activity survey or perhaps more advance surveys, for example, trapping and radio tracking. They will also advise you as to the timing and number of survey replicates required, in addition to proposed survey locations and the need for any additional equipment, for example, static recorders or night vision aids. The process of determining the need for additional investigation and/or survey effort can be complex, so you should never be afraid to ask for clarification or more information or justification as to why one or more surveys have been recommended to you.

Once all survey effort has been completed and all relevant survey data has been analysed, the licensed bat ecologist will provide you with a detailed report for submission to your planning authority or for your records, whichever is applicable. The report should clearly set out the aims and objectives of the survey work, along with a description of the survey methods, including associated limitations. The report should also clearly detail the results of the survey, in terms of the location, species and number of bats recorded as part of the outlined survey effort. Furthermore, the report should also present a discussion or evaluation of the survey results and, where appropriate, an assessment of the effects of the development, project or task on identified bat roosts, foraging areas and/or flightpaths, including recommendations for appropriate actions, mitigation, compensation and/ or requirement for any further investigation and/or licence procurement. Finally, where applicable, the report should also be supported by graphics and photographs showing survey locations and other applicable information, for example, transect routes or the location of static recorders.

Where the presence of bats has been confirmed and it has been concluded that bats will be adversely affected by the works you are proposing, your licensed bat ecologist will further advise you regarding the need for development-specific licencing, which would need to be procured from one of the UK’s non-department public bodies before works commence, for example, NatureScot’s licensing department. In addition, your licensed bat ecologist should also advise you regarding the timing of works, use of appropriate and/or approved materials and need for compensatory measures, for example, if a roost needs to be destroyed. Where applicable, they will also advise you on biodiversity enhancement options, which is a requirement under national planning policy, for example, National Planning Framework 4.

This blog forms part of our ‘Why Might I Need One’ information series. We hope the information and advice provided here is helpful in explaining why you might need and what to expect from a bat survey. If you would like to discuss any bat-related issues with us, Graham Sennhauser (our principal ecologist) is a highly experienced licensed bat ecologist and would more than happy to field any bat-related questions. He can be contacted via our contact form on our home page.

Bat-related standing advice as published by NatureScot is available via the following link. Alternatively, further advice regarding licensing for development purposes as published by NatureScot is available via the following link.

All reasonable efforts have been made to ensure the information provided in this blog is current and accurate. TETRIX Ecology will not accept any legal responsibility for errors, omissions or misleading statements in connection with this blog.