Bat Surveys, Licensing & Mitigation

Preliminary Bat Roost Assessments (PBRA)

We provide Preliminary Bat Roost Assessments (PBRAs) to determine if your building/structure or tree has bat roost suitability. This is an important first stage in deciding whether further (emergence night time) bat surveys are necessary.

If a building/structure or tree is assessed as having bat roost potential, further surveys are typically recommended; the number of surveys depend upon the level of bat roost suitability (Negligible, Low, Moderate, High).

All of our surveys are undertaken under the Bat Conservation Trust's Good Practice Guidelines 2023 by licensed surveyors.

Timing: All year round.

Bat Emergence / Re-entry / Activity Surveys

Emergence (dusk) surveys are undertaken at buildings/structures and trees assessed as having Low, Moderate or High bat roost suitability. These surveys are designed to confirm if a roost is present, and if so, the type of roost, species using the roost and numbers of bats involved.

Bat activity surveys are undertaken when it is necessary to understand how different habitats support roosting, foraging and commuting bats. Activity surveys comprise a combination of transect surveys (Ecologists walking predetermined transect routes) and automated / static bat detector surveys using bat detectors deployed at fixed locations to record bat activity remotely.

All of our surveys are undertaken under the Bat Conservation Trust's Good Practice Guidelines 2023 by licensed surveyors.

Timings: Emergence: May to August, running into September if surveys have already begun (May-August). Activity: Seasons throughout the year from April to October.

Bat Licensing & Mitigation

If a roost is confirmed, it may be necessary to proceed with works under the auspices of a European Protected Species Mitigation Licence (EPSML) from Natural England. Complete survey data is necessary for a successful licence application, together with a mitigation strategy.