Bat Roost Surveys - Kane Ecology Ltd

When do I need a Bat Roost Survey?

Bat roost surveys may be required where the application involves works upon existing buildings or trees. This applies to any works to existing buildings including demolition, restoration, refurbishment, extension or illumination. Works to trees include felling, pruning or illumination.

The Northern Ireland Environment Agency (NIEA) require all surveys to meet certain standards. These survey specifications can be viewed here: https://www.daera-ni.gov.uk/articles/site-surveys

Tree with bat roosting potential
Building with bat roosting potential

What is the process?

All surveys essentially represent a risk assessment in respect of ‘presence/likely absence’ of bats. In particular, proving ‘likely absence’ (as with proving any negative) is notoriously difficult. This is particularly true with very mobile species such as bats. A number of surveys may be required to confirm the presence or likely absence of bat roosts. The bat survey and assessment process, like all ecological surveys and assessments, is iterative with each stage informing the next. The procedure consists of the following stages/elements:

A Bat Roost Potential (BRP) survey – to assess the overall bat roosting potential of buildings or trees.
Emergence/Re-entry Bat Roost Surveys – the need for these is informed by the BRP survey and, if necessary, they are used to establish if bat roosts are present or are likely to be absent.
Bat Hibernation Roost Surveys – the need for these is informed by the BRP survey and, if necessary, they are used to establish if bat hibernation roosts are present or are likely to be absent.
Tree Climbing Bat Roost Surveys – the need for these is informed by the BRP survey and, if necessary, they are used to establish if bat tree roosts are present or are likely to be absent.
Bat Mitigation Plan – In the event that bat roosts are found a bat mitigation plan may be required detailing the mitigation measures to be employed.