Guide
Commission protected species surveys for your site
How to commission ecological surveys for development sites that may support protected species. Covers when surveys are needed, types of survey for bats, great crested newts, badgers, and nesting birds, seasonal survey windows, choosing a qualified ecologist, and interpreting survey results to determine whether you need a wildlife licence.
When you need protected species surveys
If your development involves demolition, construction, land clearance, tree felling, or changes to buildings or landscapes, you may need ecological surveys before works begin. These surveys identify whether legally protected wildlife uses your site and whether your development could affect them.
Getting surveys wrong or skipping them can halt your project and expose you to criminal prosecution. The law protects species regardless of whether you knew they were there. Commissioning surveys early is the single most effective way to avoid costly surprises.
The consequences of proceeding without surveys include criminal prosecution (up to 6 months imprisonment and unlimited fine on summary conviction, or up to 2 years on indictment), project delays of 6 to 12 months if species are discovered during works, and planning refusal where ecological information is insufficient.
What triggers the need for surveys?
You should assume surveys are needed if your development involves any of the following:
- Demolishing or converting buildings (particularly older buildings with roof voids, cellars, or hanging tiles that could support bat roosts)
- Felling or pruning mature trees (which may contain bat roosts, nesting birds, or support lichens and invertebrates)
- Clearing vegetation, hedgerows, or scrubland (which may shelter nesting birds, reptiles, or small mammals)
- Developing near ponds, ditches, or wetlands (which may support great crested newts or water voles)
- Excavating or constructing within 30 metres of known or suspected badger setts
- Working near watercourses (which may support otters, water voles, or kingfishers)
- Any development in or adjacent to a Site of Special Scientific Interest (SSSI), Special Area of Conservation (SAC), or Special Protection Area (SPA)
Your local planning authority may also have specific requirements based on local biodiversity records. Check their validation checklist before submitting a planning application.
Types of ecological survey
Ecological surveys follow a staged approach. You do not need to commission every type of survey for every site. A preliminary appraisal identifies what further surveys are needed, and you commission only what is relevant.
Stage 1: Preliminary Ecological Appraisal (PEA)
This is the starting point for almost every development project. A PEA combines a desk study (checking local biological records, historic survey data, and habitat maps) with a walkover survey of the site. The ecologist assesses the habitats present and identifies the potential for protected species.
A PEA can be done at any time of year, costs £500 to £1,500, and typically takes 2 to 4 weeks. If no potential for protected species is identified, you may proceed without further survey work.
Stage 2: Species-specific surveys
If the PEA identifies potential for protected species, you will need targeted surveys. The most common species-specific surveys for development sites are:
- Bat surveys: Preliminary Roost Assessment followed by emergence and re-entry surveys (seasonal constraints apply)
- Great crested newt surveys: Presence or absence surveys of ponds within 500 metres of the development, using eDNA sampling, torch surveys, bottle trapping, or egg searches (March to June only)
- Badger surveys: Survey for setts, latrines, paths, and feeding signs (can be done year-round, but best in late winter or early spring when vegetation is low)
- Nesting bird surveys: Breeding bird surveys if habitat clearance is planned during nesting season
- Reptile surveys: Presence or absence surveys using artificial refugia (April to June or September)
- Water vole surveys: Waterway surveys for latrines, burrows, and feeding signs (April to October)
Seasonal survey windows
Most species-specific surveys can only be carried out during defined periods of the year. Missing the survey window means waiting until the next season, which can delay your project significantly. Plan survey work as early as possible in your development programme.
Key survey seasons
| Species | Survey period | Optimum period |
|---|---|---|
| Bats (emergence surveys) | May to September | June to August |
| Great crested newts | Mid-March to mid-June | Mid-April to mid-May |
| Nesting birds | March to August | April to June |
| Reptiles | April to June, September | April to May |
| Water voles | April to October | May to September |
| Badgers | Year-round | February to April |
Critical planning point: If you commission a PEA in autumn or winter and it identifies the need for bat emergence surveys, you will not be able to complete those surveys until the following May at the earliest. This means a 6-month delay before you can submit your planning application with full survey data. Commission your PEA as early as possible, ideally before you purchase the site or finalise your development programme.
Choosing a qualified ecologist
The quality of your ecological surveys depends on the ecologist you appoint. A poorly conducted survey can lead to incorrect conclusions, planning refusal, or legal liability.
What to look for
- CIEEM membership: Members of the Chartered Institute of Ecology and Environmental Management are bound by a code of professional conduct
- Survey licences: Bat surveyors must hold a Natural England bat survey licence (Class Licence CL18 or equivalent). Great crested newt surveyors need a licence for eDNA sampling. Ask to see licence numbers
- Relevant experience: Ask for examples of similar projects in scale and type
- Professional indemnity insurance: Essential if survey conclusions prove wrong and you face prosecution or delays
Key questions before appointing
- What surveys do you recommend, and what are the seasonal constraints?
- Can you provide a fixed-fee quote covering all recommended survey stages?
- What is the shelf life of the survey data (typically 12 to 18 months)?
- If a mitigation licence is needed, can you act as the named ecologist?
Typical costs
- Preliminary Ecological Appraisal: £500 to £1,500
- Bat Preliminary Roost Assessment: £300 to £800 per building or tree
- Bat emergence surveys: £500 to £1,200 per visit (multiple visits usually required)
- Great crested newt eDNA survey: £400 to £800 per pond
- Full ecological survey package: £2,000 to £10,000+ depending on site size and complexity
Interpreting survey results
Survey reports lead to one of three outcomes for your development:
No protected species found
You can proceed subject to standard precautions. Your ecologist should still recommend timing vegetation clearance outside bird nesting season (March to August), since nesting birds are protected regardless of survey findings.
Protected species confirmed - licence required
If your development would affect confirmed protected species, you need a mitigation licence from Natural England. The application must demonstrate the three derogation tests (overriding public interest, no satisfactory alternative, favourable conservation status maintained). Allow at least 30 working days for determination. Licence fees apply under the Wildlife Licence Charges (England) Order 2025.
Protected species confirmed - avoidance possible
In some cases, impacts can be avoided through careful timing and method without a formal licence. For example, vegetation clearance outside nesting season, or installing bat boxes before demolishing a building with a low-status roost. Your ecologist will advise whether reasonable avoidance measures are appropriate.
Survey shelf life: Survey data is typically valid for 12 to 18 months. If your planning application is delayed beyond this period, you may need update surveys.
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1. Commission a Preliminary Ecological Appraisal
Appoint a CIEEM-registered ecologist to carry out a PEA of your site as early as possible in the project. The PEA combines a desk study of local biological records with a walkover survey. It identifies the habitats present and assesses the potential for protected species. A PEA can be done at any time of year, costs £500 to £1,500, and typically takes 2 to 4 weeks to complete.
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2. Review PEA recommendations and plan further surveys
The PEA report will recommend whether species-specific surveys are needed and for which species. Check the seasonal survey windows immediately. If bat emergence surveys are recommended and it is already October, you will not be able to complete them until the following May. Build survey timescales into your project programme and budget.
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3. Commission species-specific surveys within seasonal windows
Instruct your ecologist to carry out the recommended species-specific surveys during the correct season. For bats, this means emergence and re-entry surveys between May and September. For great crested newts, surveys must be completed between mid-March and mid-June. For badgers, surveys can be done year-round but are best in late winter. Ensure all survey visits are completed before your planning application target date.
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4. Receive and review survey reports
Your ecologist will produce a report for each survey, setting out findings, conclusions, and recommendations. Review these with your ecologist to understand the implications for your development. Key questions to ask are whether a mitigation licence is needed, what the likely timescale for licence determination is, whether the development design can be modified to reduce impacts, and what mitigation measures are recommended.
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5. Prepare mitigation strategy if protected species are confirmed
If protected species are found and your development would affect them, your ecologist prepares a mitigation strategy. This sets out how impacts will be avoided, reduced, or compensated. The strategy forms part of any licence application and may also be required by the local planning authority as part of your planning submission.
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6. Submit survey reports with your planning application
Include all ecological survey reports, the mitigation strategy, and any licence application details with your planning submission. The local planning authority will consult Natural England on applications affecting protected species. Incomplete ecological information is a common reason for planning delays or refusal.
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7. Apply for wildlife licences if required
If a mitigation licence is needed, submit the application to Natural England (or the relevant devolved authority) with your completed survey data, mitigation strategy, and method statement. Allow at least 30 working days for determination. Include the application fee. Your named ecologist must be identified on the application.
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8. Implement mitigation measures under ecologist supervision
Once the licence is granted, works must follow the licence conditions exactly. Your named ecologist supervises all licensed activities. Brief all contractors on the constraints before they start work. Keep the licence on site and report any incidents to Natural England immediately.
Common mistakes to avoid
- Commissioning surveys too late: The most common and most expensive mistake. If you need bat surveys but it is already October, you face a 7-month wait until the next survey season opens in May
- Appointing an unqualified surveyor: Surveys must be carried out by ecologists with appropriate licences and experience. Planning authorities and Natural England will reject reports from unqualified surveyors
- Clearing vegetation before surveys: Removing hedgerows, scrub, or trees before completing surveys does not remove the legal protection. If protected species were present, you have committed an offence regardless of whether you knew
- Ignoring nesting bird season: There is no licence available to disturb nesting birds for development purposes. If an active nest is found, all works in that area must stop until chicks have fledged
- Assuming small sites are low risk: A single mature tree can support a bat roost. A garden pond can support great crested newts. Site size alone does not determine ecological risk
- Letting survey data expire: Survey data has a shelf life of 12 to 18 months. If your project is delayed, you may need to commission update surveys at additional cost