Placement of Bat Boxes on Bridges to Enhance Bat Roosting Habitat

Focus Area

Wildlife & Ecosystems


Natural Resources






1-2 years

Research Idea Scope

Bridges built in previous decades often incorporated
expansion joints that provided optimal roosting habitat for bats.  This is due to the combination of favorable
gap size, open canopy in road corridors and thermal mass characteristics of
concrete or steel structures.  New
bridges are often constructed with prefabricated concrete structures that lack
the optimal gap size, but retain the thermal characteristics necessary for
bats.  A low cost approach to replacing
bat habitat would be to attach bat houses to new bridges, but the precise
placement and configuration of the bat houses for optimal use is unknown.  Additionally, it may be that different
species of bats would prefer different placement.  With white nose syndrome reducing bat
populations in the east at an alarming rate, having managed and easily
available roosting structures may allow for novel management techniques to
combat the disease and restore populations. 
If a vaccine or treatment for white nose syndrome becomes available in
the future, it may be possible to treat roosting boxes so that the treatment is
transferred to the bats.  

Urgency and Payoff

Bat populations are in steep decline due to emerging
pandemic.  Loss of roosting habitat can
exacerbate the decline.  Bat box
construction on bridges may provide beneficial mitigation for both threats.  

Suggested By

Jason Mays, USFWS 828 258-3939

[email protected]