Bat survey licences and what each level allows
A bat surveyor's licence sets the limit of what they may lawfully do on site. Here is what each tier permits, how class licences work, and the checks to make before you instruct.
Bat survey licence levels decide what a surveyor is lawfully allowed to do on your site, and they are not a matter of professional preference. All bat species in the United Kingdom are European protected species under the Conservation of Habitats and Species Regulations 2017, and they are also protected under the Wildlife and Countryside Act 1981. Disturbing a bat or obstructing access to a roost without a licence is an offence. So the first question to ask an ecologist is not what the survey will cost. It is what their licence permits.
Why a licence is needed before anyone enters a roost
The protection covers the animal and the place it uses for shelter, whether or not a bat is present at the time. A roost that is unoccupied in January is still a roost.
Two consequences follow for anyone commissioning work. A preliminary roost assessment, which is an external and internal inspection looking for bats and for evidence of them, may be carried out without a licence where it does not involve disturbance or entering a roost void. Anything that involves handling, entering an enclosed roost, using an endoscope in a crevice, or deliberately disturbing bats requires a licence from Natural England.
The line between inspection and disturbance is finer than it sounds. Lifting a ridge tile, opening a soffit or putting a light into a cavity where bats are present can be disturbance. A surveyor working without the right licence has to stop at the point where the evidence becomes interesting, which is exactly where the application needs answers.
Survey licences and what the tiers permit
Natural England issues survey licences for scientific, educational and conservation purposes, and they are tiered. The tiers are commonly described as levels, with each level adding techniques rather than replacing the one below.
| Broad tier | Typical techniques permitted |
|---|---|
| Entry level | Roost inspection, disturbance of bats during inspection, use of an endoscope |
| Intermediate | Capture and handling of bats by hand, including from known roosts |
| Advanced | Static and hand net capture, harp trapping, mist netting |
| Specialist | Radio tagging, tracking and other invasive research techniques |
The names, reference numbers and precise scope of each tier are set by Natural England and are revised from time to time, so read the conditions on the licence document itself rather than relying on a description of the level. A licence also names the individual. It does not extend to their colleagues, their subcontractor or their graduate assistant unless that person is separately licensed or named as an accredited agent.
For a standard development project, the entry and intermediate tiers cover almost everything the survey work requires. Trapping and tagging belong to research projects and to unusual mitigation cases, and an ecologist proposing them for a single dwelling extension has misunderstood the brief.
Class licences and registered consultants
Alongside individual licences, Natural England operates class licences that registered consultants may work under without applying for a project specific licence each time. The Bat Low Impact Class Licence is the one that matters most in development. It allows a registered consultant to carry out works affecting small numbers of the more common species at roosts of low conservation significance, following a set method and reporting afterwards.
Registration is the point to check. A consultant must be accepted onto the register, which requires evidence of experience, and their registration can be withdrawn. Working under a class licence also brings conditions on record keeping, notification and annual reporting that an unregistered consultant cannot meet.
Where a class licence does not fit, because the species is rarer, the roost is more significant or the works are more extensive, a project specific mitigation licence is needed instead. The article on bat licence classes and what each one allows goes through that distinction in more detail.
Mitigation licences and the three derogation tests
A mitigation licence, often called a European protected species licence, permits works that would otherwise be an offence. Natural England may grant one only where three tests are met.
- The activity is for a purpose the Regulations permit, in development cases usually imperative reasons of overriding public interest.
- There is no satisfactory alternative.
- The action will not be detrimental to the maintenance of the population of the species concerned at a favourable conservation status in its natural range.
Two practical points follow. Natural England will not usually grant a licence before planning permission exists, so the licence sits after consent in the programme and before works start. And the local planning authority has to consider those same tests itself when it decides the application, because it cannot grant permission for a scheme that could never be licensed. That is why an officer will ask for the mitigation strategy at application stage rather than accepting a condition requiring one later.
Checking a consultant before you instruct them
Ask for four things, and read the answers.
The licence document itself, showing the holder's name, the tier and the expiry date. Their registration status for any class licence they intend to rely on. Professional membership, since a chartered or full member of the Chartered Institute of Ecology and Environmental Management is subject to a code of conduct and a competency framework. And the names of the people who will actually be on site, checked against the licence.
Then ask about the season. Emergence and re-entry surveys are seasonal work, and the survey effort expected follows the roost suitability assessed at the preliminary stage. Low suitability typically justifies one survey visit, moderate two and high three, within the optimal part of the season. A consultant who promises a full survey suite in November is either planning to work outside good practice or has not understood the site.
An illustrative example: a barn conversion assessed as having high roost suitability. The preliminary roost assessment in March found droppings and a small number of feeding remains. Three emergence surveys were programmed across May, June and July. The planning application was submitted in August with the protected species survey complete and a mitigation strategy showing replacement roosting features. The licence application went in after permission. Nothing about that sequence can be compressed without breaking either the guidance or the law.
What the council checks in the report
A case officer, or the authority's ecologist where it has one, will look for the licence number and holder, the dates and weather conditions for each survey visit, the equipment used, the number of surveyors and their positions, the survey effort against the assessed suitability, and whether the conclusions follow from the data recorded.
They will also look for the mitigation hierarchy applied in order: avoid, then mitigate, then compensate. A report that jumps to bat boxes without explaining why the roost cannot be retained will be sent back.
Where the survey work sits within a wider ecological appraisal, the preliminary ecological appraisal is the document that should have identified the need for bat work in the first place, and a mismatch between the two is the sort of inconsistency that costs a determination period.
Where an unlicensed survey leaves you
In the worst case, an offence has been committed. More commonly, the survey is given little or no weight, the authority requires the work to be redone by a suitably licensed ecologist, and the timing means waiting for the next season. A refusal on inadequate ecological information is straightforward for an authority to defend at appeal, because the burden of demonstrating no harm to a protected species sits with the applicant.
PlanScope can draft the supporting documents that sit around this work and flag where survey data is missing, and the survey and any licence application require a suitably licensed ecologist. Our drafts are a starting point for that professional rather than a substitute for them. You can find a reviewer through the professional directory.
This is general guidance rather than legal advice. Check the position with Natural England or a suitably licensed ecologist before relying on it.
PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. For specialist technical reports, qualified professional input may be required.
Frequently asked questions
Do I need a licence for a preliminary roost assessment?
Usually not, where the inspection does not involve disturbing bats or entering an enclosed roost void. The moment work involves handling, endoscope use in an occupied crevice, lifting tiles over bats or deliberate disturbance, a Natural England licence is required. In practice most competent ecologists carrying out these assessments hold a survey licence anyway.
Does a licence cover the whole consultancy?
No. A survey licence names an individual. It does not extend to colleagues, subcontractors or assistants unless they hold their own licence or are named as accredited agents on it. Ask for the names of the people who will actually be on site and check them against the licence document before the visit is booked.
When can a mitigation licence be applied for?
Natural England will not usually grant a European protected species licence before planning permission exists, so it sits after consent and before works begin. The local planning authority must nonetheless consider the three derogation tests when it decides the application, which is why officers expect the mitigation strategy with the application rather than by condition.
How many emergence surveys does a site need?
The effort follows the roost suitability assessed at the preliminary stage. Low suitability typically justifies one visit, moderate two and high three, carried out within the optimal part of the season. A consultant offering a full survey suite outside that season is either working outside good practice guidance or has misread the site.
What happens if the survey was done without a licence?
At worst an offence has been committed. More often the report is given little weight, the authority requires the work to be redone by a suitably licensed ecologist, and the timing pushes the application into the next survey season. Refusal for inadequate ecological information is straightforward for an authority to defend at appeal.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.