Bat Surveys

There are 18 species of bat in the UK with many species roosting within buildings. These bat roosts can be present within the roof void of a building or within crevices, such as under tiles or within cavity walls.

All bat species and their roosts are legally protected by both domestic and international legislation. It is a criminal offence to:

  • Deliberately capture, injure or kill a bat;
  • Intentionally or recklessly disturb a bat in its roost or deliberately disturb a group of bats;
  • Damage or destroy a bat roosting place (even if bats are not occupying the roost at the time);
  • Intentionally or recklessly obstruct access to a bat roost.

When considering the approval of your development proposals, the local planning authority and licensing agencies require information to determine the effects of the development on bats, to identify which species, if any, are present and to identify if mitigation, compensation or enhancement measures are required.

Our experienced team of licenced ecologists can carry out bat surveys to inform a planning application and to devise a mitigation strategy where necessary. All surveys are carried out in accordance with the Bat Conservation Trust (BCT) guidelines (Collins, 2016). A description of the various stages is provided below.

Phase 1 bat survey

A phase 1 bat survey is an initial inspection of any building, tree or other suitable feature for roosting bats that could be impacted upon by a proposed development. This survey may be conducted at any time of the year.

Where a building/structure has been determined as being a confirmed roost or has the potential to support bat roosts then phase 2 surveys will be required. These surveys will determine if bats are present and also identify the species and number of bats alongside determining access points. This is all crucial information to inform a mitigation strategy to support any planning application.

Phase 2 bat survey (emergence/re-entry survey)

Phase 2 surveys can only be completed during the bat activity survey season which runs between May and September with the peak survey season between May and August. These surveys are conducted at night when bats are active and experienced surveyors will monitor the building/structure as bats emerge or re-enter their roost sites. The number of surveys required will depend on the potential of the building and ranges from 1 to 3 and surveys must be spread at least two weeks apart. Following the completion of these surveys a detailed mitigation strategy will be devised which can then be submitted as part of the planning application.

Licencing process

Where a bat roost has been confirmed within a building/structure a licence will be required from Natural England for any activity which would otherwise be considered a legal offence. This licence can only be applied for once planning permission has been obtained. We have an experienced team of ecologists who can prepare the documents and carry out the mitigation on the ground.

Other survey types

For more complex planning applications more detailed surveys may be required where foraging or commuting habitat may be lost as part of the development of the site. Our team of ecologists can provide advice and guidance on the types of surveys required and provide assistance in detailing timings for surveys to aid any planning application.