The bat roost trigger index is an Excel-based tool aimed at helping to evaluate the suitability of structures and buildings to support summer bat roosts. It has been designed to be used in preliminary bat roost assessments (PRAs) to augment professional judgement and allow numerical comparison of different structures and buildings. This will help bat surveyors to maintain a consistent and systematic approach to their assessments across a range of structure or building types, characters and ages.

The tool can be freely downloaded here, and contains further information on the background, limitations and instructions for use.

It must be stressed that the tool is a working prototype which requires extensive testing and critical appraisal.

Please feel free to use and test the tool in your PRAs; however, we would ask you to provide feedback to help us make necessary adjustments and improvements to future versions of the tool.

Email feedback or other enquiries to:

All feedback will be treated with the utmost confidence and your details will not be shared.

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