Badger survey timing across the year

Badger survey timing is unusual among protected species work because the survey itself has no closed season. A sett can be found and classified in August or in January. What has a season is the licence you need to interfere with a sett, and in England that licence is normally issued only between 1 July and 30 November. So the survey is flexible and the mitigation is not, and a programme built on the first fact without the second loses eight months.

Badger work is survey and licensing work for a suitably experienced ecologist, and the licence application itself relies on that person's evidence.

What can be surveyed at any time of year

Sett searches, field sign surveys and habitat appraisal can be done in any month. The ecologist walks the site and a buffer around it looking for sett entrances, spoil heaps, well-worn paths, latrines, snuffle holes, hair caught on fence wire and scratching posts, and records each against a standard classification.

Setts are classified by type and by use. The types run from main setts, which are the breeding centre of a social group and usually have several entrances with large spoil heaps, through annexe and subsidiary setts, to outlier setts with one or two holes and little sign of activity. Use is classified as well used, partially used or disused, and the difference between those three matters because the licensing and mitigation requirements follow from it.

A single visit establishes what is present. It does not establish how the group uses the site across a year, which is why a sett found in one visit often leads to further work.

When sett activity is easiest to establish

Late winter into early spring is the easiest period. Vegetation is low, paths and latrines are visible, and fresh spoil shows clearly against wet ground. Bramble and bracken in July hide entrances that were obvious in February.

Activity is also easier to judge then. Badgers renew bedding in late winter and early spring, so discarded bedding at an entrance is a strong indicator. Where the classification is contested, camera traps left for two to three weeks give a defensible record of which entrances are in use, and they cost little relative to the consequence of getting it wrong.

Summer surveys are perfectly valid and they need to be reported honestly. If the survey took place in dense vegetation, say so, state the limitation, and explain why the conclusion still holds or what further work is proposed.

Bait marking and its narrow window

Bait marking establishes territory boundaries and which setts belong to which social group. Coloured indigestible markers are mixed into bait, fed at specific setts over several weeks, and the markers are then found in latrines, showing where that group ranges.

The window is short. The work is normally done in late winter and early spring, roughly February to April, before dense vegetation makes latrine searching impractical and while territorial marking is at its clearest. It also has to avoid the period when cubs are heavily dependent.

Bait marking is not needed on every site. It is needed where a scheme will remove or isolate part of a territory, where several setts lie within and around the site and their relationship is unclear, or where a mitigation strategy depends on knowing that an artificial sett will be within the group's range. Where it is needed and the window has passed, there is no substitute, and the programme waits.

Licensing seasons for sett closure and exclusion

Interfering with a badger sett is an offence under the Protection of Badgers Act 1992, which protects badgers from being killed, injured or taken, and protects setts from damage, destruction and obstruction, including disturbance of a badger while it occupies a sett. Development that requires a sett to be closed needs a licence from Natural England.

Licences for sett closure and exclusion in England are normally granted for the period from 1 July to 30 November. The closed period, from 1 December to 30 June, reflects the breeding cycle: cubs are born in the depths of winter and remain dependent well into the following summer, so closing a sett in spring risks trapping and killing dependent young.

That single constraint governs the programme:

1. Survey and classify the setts, at any time of year
2. Carry out bait marking if the mitigation strategy needs it, in the late winter window
3. Design the mitigation, including any artificial sett, and submit the licence application with the survey evidence
4. Build the artificial sett and allow it to weather and be adopted, which takes months rather than weeks
5. Close and exclude within the 1 July to 30 November window
6. Carry out the development works that affect the sett location afterwards

Why the licensing season drives the programme

Work backwards from the season and the arithmetic becomes obvious. An artificial sett usually has to be constructed the season before closure, so that badgers have had the chance to find it. Licence applications take time to determine, and Natural England will refuse an application that lacks adequate survey evidence.

So a scheme that discovers a main sett in September has realistically lost that year's window, because the artificial sett cannot be built, weathered and adopted in time. Discovering the same sett in the previous winter would have allowed bait marking in February, an artificial sett built in spring, and closure the following autumn.

This is the argument for commissioning an ecological appraisal early. A Preliminary Ecological Appraisal in the first weeks of a project costs little and identifies whether badgers are a programme issue at all. Our note on planning a survey budget across two financial years covers how to hold the cost across the year end, and discharging pre-start conditions for a spring start covers the sequencing where the works season and the licence season pull apart.

Illustrative example: a farmyard conversion where a survey in November finds a partially used annexe sett beneath a collapsed wall, bait marking in the following February confirms it belongs to a group with a main sett 180 m away in a copse, an artificial sett is built in April, and closure is licensed in September. Details here are illustrative only.

Protecting setts while work goes on around them

Most schemes do not need a sett closed. They need to work near one without disturbing it, and there are well established distances used in licensing practice.

Disturbance to a badger in a sett can be an offence, and licensing guidance treats the use of heavy machinery within 30 m of a sett entrance, lighter machinery within 20 m, and hand digging or light work within 10 m as activities likely to require a licence. Those distances are the starting point for a construction exclusion zone.

Practical measures that authorities and Natural England expect:

• A fenced exclusion zone marked on the construction plan, not just described in the report
• No material storage, welfare units, parking or spoil within the zone
• Covered or ramped excavations left open overnight, so badgers that fall in can get out
• Pipes capped at the end of each shift
• No night lighting directed at the sett or at known commuting routes
• A named person responsible on site, with a toolbox talk recorded

What the authority expects to see

A badger report accompanying an application should give the sett locations, the classification of each sett by type and use, the evidence behind that classification, the survey date and the limitations, and the mitigation strategy with its licensing programme.

One point on presentation. Sett locations are usually supplied in a confidential annex rather than in the public document, because badger persecution is a real risk and publishing precise locations increases it. Say in the public report that a confidential annex has been provided to the authority.

Then expect conditions: a construction environmental management plan securing the exclusion zone, a requirement for an updated survey if works are delayed beyond a stated period, and a requirement that any licence is obtained before the relevant works begin. A Protected Species Survey prepared to that standard is what turns a badger constraint into a manageable programme item. Enter your postcode on PlanScope to see which ecology reports a site is likely to need.

This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified professional 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.