Temporary Deterrence of Bats from Bridges Using Ultrasonic Deterrents

White-Nose Syndrome and increased disturbance of habitats used by bats for roosting and foraging has led to a growing concern about the bat population in the US in the last decade. Bridge repair and replacement projects are required to follow additional regulatory requirements to avoid and minimize impacts to bats when protected bat species are present on bridges. Some of these requirements (e.g., timing restrictions) are challenging to implement, given Minnesota’s short construction season. The objective of this project was to evaluate the feasibility and efficacy of deploying non-lethal ultrasonic acoustic devices in the field to temporarily deter bats from roosting on bridges ahead of construction or maintenance activities, while minimizing harm to bats and non-target species. The technology was evaluated at two test sites located in Minnesota, one short term and one long term, during the summer of 2019. Considering the findings from both acoustic monitoring data and the field inspections, acoustic deterrents appear to effectively work to temporarily deter bats from select abutments and present an option to temporarily deter bats at construction sites. The implementation of this technology by any transportation agency will require the development of an agency protocol, through collaboration of relevant offices.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: 18p

Subject/Index Terms

Filing Info

  • Accession Number: 01763975
  • Record Type: Publication
  • Report/Paper Numbers: TRBAM-21-02774
  • Files: TRIS, TRB, ATRI
  • Created Date: Dec 23 2020 11:16AM