Case Study 2 – Environmental: Infrastructure


SPONSOR: ANV Measurement Systems

PROJECT: Acoustic Deterrents as a Bat Mitigation Strategy

COMPANY: Temple Group, The Ecology Consultancy, BSG, University of Bristol and HS2


Eighteen species of bats are present in the UK. Their sensitive and highly evolved acoustic apparatus, coupled with complex habitat requirements and wide-ranging use of the landscape, means they are vulnerable to disturbance, habitat fragmentation and killing or injury caused by a wide range of development projects.

There are emerging approaches to using acoustic output as a mitigation methodology to dissuade bats from sites such as windfarms that pose a risk of killing and injuring them, but little attention has been paid to the use of sound to enhance the effectiveness of mitigation.

Instead of simply excluding bats from an area, the consultants determined that acoustic deterrents can be used to deter bats while ensuring normal levels of bat behaviour in the vicinity remain the same.

They assessed the sound emitted and adapted the design by changing the configuration of acoustic deterrents to maximise their effectiveness in eliciting localised and predictable changes in bat flight behaviour.

This involved recording changes in bat flight behaviour in response to acoustic stimuli.

This research was carried out to evaluate acoustic deterrents as part of mitigation measures designed for protection of woodland bats present along part of the High Speed 2 (HS2) Phase 1 railway. This could be a new and widely applicable approach.

This was a very different entry than most. It was a practical solution to a problem affecting a major infrastructure project and good to see acoustic consultants helping to satisfy Natural England whose consent was required to enable the project to go ahead.

The mixture of ecology with acoustics makes this stand out and it also receives an award for innovation.