Guidance

Guide to using bat mitigation class licence CL21: registration criteria, how to apply and if you need to pay

Updated 14 May 2024

Applies to England

There are no planned training workshops to become a registered consultant. Natural England is reviewing this licence and will then decide whether to run future workshops for the CL21 licence.

How it works

The bat ‘low impact’ licence (CL21) is a mitigation class licence. You should consider what impact your actions will have on bats. If you cannot avoid affecting them at a site, you can use this licence:

• to disturb and capture up to 3 ‘common or widespread’ bat species (which are those listed in each annex)
• to damage or destroy up to 3 ‘low conservation status roosts’ (these are: feeding, day, night and transitional roosts)
• if you’re a registered ecological consultant (‘registered consultant’)
• if your action has a low or temporary impact on bats or their roosts
• if sites are registered before you start work

If your project does not meet these conditions, then you should apply for an individual bat mitigation licence.

You must apply to become a registered consultant. You can only apply as an individual. You cannot apply as a group or consultant practice. This means every consultant meets the criteria for this licence.

Natural England decides if you’re eligible and invites you to attend a compulsory 2 day training workshop. You must pass the training assessment. If you pass, you’ll get a registration number. This allows you to apply to register sites and carry out works.

You must use the licence annex appropriate to your location and the species affected.

Works should be short term and usually only last for up to 6 months. You must submit a report of actions taken for each registered site, including nil returns.

Registration criteria

You must show you’ve held (as a minimum) a current level 2 bat class survey licence for at least 3 years - which must include disturbance and handling of bats for that period.

You must have evidence that you’re a full member of a relevant professional body or you’ve been an associate member for at least 3 years. This could include organisations, such as the:

• Chartered Institute of Ecology and Environmental Management (CIEEM)
• Institute of Environmental Management and Assessment (IEMA)
• Chartered Institute of Water and Environmental Management (CIWEM)
• Royal Institution of Chartered Surveyors (RICS)

You must be able to show from previous mitigation licences that you:

• carried out the majority of surveys
• carried out the majority of impact assessments
• designed the majority of project plans to include compensation and mitigation measures
• undertook the majority of the licensed works
• submitted all bat survey licence return forms
• met the deadlines and conditions for submitting licence returns - this includes full details of actions taken

You must be able to show you:

• can work on a range of roost types including higher conservation status roosts not covered by CL21 (such as a maternity roost or hibernation roost)
• have experience and understanding of a range of licensable methods, such as using endoscopes

You must:

• keep your skills and development up to date with continuing professional development
• not have been convicted of wildlife-related or animal welfare offences in the last 5 years

Use the right annex

There are 4 annexes to CL21. You must meet the criteria for the annex that’s right for your location and the bat species you’re working with.

Existing registered consultants

If you’re already registered to use CL21, you should continue to use Annex B. You can apply to use Annex C and Annex D too, but you must make sure you meet the additional criteria.

Using accredited agents

You can use up to 2 accredited agents to carry out works on your behalf if:

• you’re certain they’re experienced to work with the affected bat species and in the methods they’ll use
• they’ve held (as a minimum) a current level 2 bat class survey licence for at least 3 years

They must have also been one of the following:

• a named accredited agent (or the named ecologist) on at least 2 mitigation licences in the last 3 years
• a named accredited agent (or the named ecologist) on at least 3 science and research licences in the last 4 years
• a named assistant on 4 CL21 licence return reports in the last 3 years

You must oversee the licensed work and make regular visits to monitor the site. You’re responsible for works carried out on site. You must keep records of:

• the accredited agents you use
• evidence that they meet the qualifying criteria

Annex A

You can only use Annex A in northern England in the counties (including unitary authorities) of:

• County Durham
• Cumbria
• East Yorkshire
• Lancashire
• Northumberland
• North Yorkshire
• South Yorkshire
• West Yorkshire

You cannot use this annex with any other annex.

What you’re allowed to do

You can damage and destroy no more than 3 low conservation status roosts. Of these roosts, you can disturb and capture - in appropriate small numbers - no more than 3 common species of:

• common pipistrelle
• soprano pipistrelle
• brown long-eared

Experience you must have

You need to show that you were the named ecologist on bat mitigation licences in the last 4 years for these 3 species:

• common pipistrelle
• soprano pipistrelle
• brown long-eared bat

You need evidence of 3 licence survey returns from the last 3 years of any mix of:

• whiskered
• Brandt’s
• Daubenton’s
• Natterer’s
• any other species present in the counties relevant to this annex

You must also meet one of these 3 conditions (known as ‘scenarios’).

Scenario 1

You’ve been the named ecologist on at least 5 mitigation licences in the last 4 years, one of which has been issued in the last 12 months.

Scenario 2

You’ve been the named ecologist on at least:

• 3 mitigation licences in the last 4 years, one of which has been issued in the last 12 months
• 3 science or research licences in the last 4 years

Scenario 3

You’ve been the named ecologist on at least:

• 2 mitigation licences granted in the last 4 years, one of which has been issued in the last 12 months
• 2 science or research licences in the last 4 years

You must also be:

• registered as a volunteer bat roost visitor trainer and actively carrying out bat roost visits for the Bat Advice Service
• an active member of a local bat group for at least 18 months

Annex B

You can use Annex B in all counties (including unitary authorities) in England. If you want to use Annex C or Annex D at the same time, you must be registered for Annex B too.

What you’re allowed to do

You can damage and destroy no more than 3 low conservation status roosts. Of these roosts, you can disturb and capture, in appropriate small numbers, no more than 3 common species of:

• common pipistrelle
• soprano pipistrelle
• brown long-eared
• whiskered
• Brandt’s
• Daubenton’s
• Natterer’s

If you use this annex with Annex C or D for multi-species’ roosts, you can only affect up to 3 roosts in total.

Experience you must have

You need to show that you were the named ecologist on bat licences for at least 5 bat species. The licences need to show at least one species from these groups:

• Pipistrellus
• Plecotus
• Myotis or Rhinolophus

You must also meet one of the following 3 scenarios.

Scenario 1

You’re the named ecologist on at least 5 mitigation licences in the last 4 years, one of which has been issued in the last 12 months.

Scenario 2

You’re the named ecologist on at least:

• 3 mitigation licences in the last 4 years, one of which has been issued in the last 12 months
• 3 science or research licences in the last 4 years

Scenario 3

You’re the named ecologist on at least:

• 2 mitigation licences granted in the last 4 years, one of which has been issued in the last 12 months
• 2 science or research licences in the last 4 years

You must also be:

• registered as a volunteer bat roost visitor trainer and actively carrying out bat roost visits for the Bat Advice Service
• a member of a local bat group for at least 18 months

Scenario 4 (for exceptional circumstances only)

You can only use Scenario 4 if:

• you’ve not held sufficient individual licences in the last 4 years
• you can show you’ve extensive knowledge and experience of bat ecology, surveys and mitigation

Show your experience

You should use the most recent evidence you have to show your experience. You must have experience of:

• planning and carrying out suitable surveys
• assessing impacts
• designing and carrying out mitigation, compensation or enhancement work
• any related conservation work

Evidence of your experience can include:

• ecological surveys and mitigation plans that you’ve produced in support of planning applications
• mitigation licences that you’ve held

You must show examples of your in-depth knowledge of bat ecology such as:

• designing robust schemes that avoid or lessen impacts
• implementing mitigation and compensation measures, as required
• working with a variety of bat species and roost types

Evidence of your experience can include:

• planning or participating in monitoring or research projects
• advising on large scale development projects
• planning and delivering recognised training courses
• being responsible for protected sites

Natural England will aim to assess a ‘Scenario 4’ application within 15 working days. It can reserve the right to request additional information, including reports that you’ve produced.

Annex C

You can only use Annex C in southern England in the counties (including unitary authorities) of:

• Berkshire
• Buckinghamshire
• Devon
• Dorset
• East Sussex
• Essex
• Greater London
• Hampshire
• Hertfordshire
• Kent
• Oxfordshire
• Somerset
• Surrey
• West Sussex
• Wiltshire

What you’re allowed to do

You can:

• damage and destroy no more than 3 feeding, day, night and transitional serotine bat roosts
• disturb and capture serotine bats in appropriate small numbers

If you cannot mitigate against impacting serotine bats or their roosts, you must provide compensation measures.

If you use this annex with Annex B or D for multi-species’ roosts, you can only affect up to 3 roosts in total.

Experience you must have

You must meet the criteria for Annex B and you need to show either:

• you were the named ecologist on 2 mitigation licences for serotine bats in the last 3 years
• you’ve held one mitigation licence and you can detect and assess serotine bat roosts - you’ll need evidence, such as survey returns for the last 3 years

You can use the criteria for Annex B Scenario 4 in exceptional circumstances. You must still show substantial knowledge and experience of working with serotine bats.

Annex D

You can only use Annex D in south west England in the counties (including unitary authorities) of:

• Cornwall
• Devon
• Dorset
• Gloucestershire
• Herefordshire
• Somerset
• Wiltshire

What you’re allowed to do

You can:

• damage and destroy the roosts of no more than 3 low conservation significance day and transitional lesser horseshoe bat roosts
• disturb and capture lesser horseshoe bats in appropriate small numbers

If you cannot mitigate against impacting lesser horseshoe bats or their roosts, you must provide compensation measures.

If you use this annex with Annex B or C for multi-species’ roosts, you can only affect up to 3 roosts in total.

Experience you must have

You must meet the criteria for Annex B and you need to show either:

• you were the named ecologist on 2 mitigation licences for lesser horseshoe bats in the last 3 years
• you’ve held one mitigation licence and you can detect and assess lesser horseshoe bat roosts - you’ll need evidence, such as survey returns for the last 3 years

You can use the criteria for Annex B Scenario 4 in exceptional circumstances. You must still show substantial knowledge and experience of working with lesser horseshoe bats.

Other qualifying criteria

You may qualify if you’re one of the following groups.

If you’ve had a career break in the last 4 years

You must meet the same criteria for all annexes over a 5 year period to qualify for CL21.

If you have a disability

If you have a disability that makes it difficult for you to meet the criteria, you should email Natural England at [email protected].

How to apply

Use the form for the annex that’s right for you. Annex C or Annex D is a joint form, which you can use for either annex.

Save the relevant forms to your computer before you fill them in. Right-click on the link to the form and select ‘Save target as’ or ‘Save link as’.

Natural England recommends you do not use a tablet or mobile device.

You can use the free Adobe Acobat Reader to complete a form.

Save your changes as you fill in a form. If you do not do this, you risk losing your work.

If you have any problems, email [email protected].

Sign and submit your form

By ticking the boxes in ‘Section 5. Declarations’, you are signing the form.

To submit the form, attach your completed form to an email addressed to Natural England at [email protected].

Result of your application

Natural England will decide if you’re eligible to become a registered consultant. It will tell you by email within 15 working days of receiving your application. If you fail to meet the criteria, you’ll be told why.

Compulsory training

If you’re eligible to be a registered consultant, Natural England will invite you to the next available 2 day training workshop. The workshop covers all the requirements for holding CL21, such as:

• understanding the relevant licensing laws
• how you use the licence
• how to complete registration and return forms

You’ll need to pass an assessment as part of the workshop.

You’ll need to pay for the training and overnight accommodation. You’ll get full details in your invitation email.

How to register a site and find out if you’ll need to pay

You’ll get a registration number when you’ve passed the assessment. Use this number to register sites on your licence. You’ll be given access to an online forum for:

• the forms you need
• a copy of licence CL21

You may need to pay for a site registration

You may need to pay for a site registration for certain development work. Fill in the charge screening form that’s on the online forum and send with your site registration form. Natural England will assess these and tell you:

• if you need to pay
• how much you’ll pay

Read the terms and conditions for paying for a wildlife licence.

When you do not need to pay

You will not pay for a licence if it’s for:

• conservation of bat roosts in their original position
• conservation of a historic property
• domestic home improvements
• preservation of public health and safety

How to pay

Natural England will send you an invoice when it approves your application.

You can pay by:

• electronic bank transfer
• debit or credit card by telephone - except American Express
• cheque

Your invoice will give details for these payment methods.

You need to include the invoice number with your payment so Natural England can match it to your application.

VAT does not apply to charges for wildlife licences.

Natural England accepts purchase orders. If you want Natural England to add a purchase number to your invoice, you must include it in the invoice details in your charge form.