Homes for Homeless Bats — A Win—Win solution

When properly implemented, well in advance of scheduled displacement, bat houses can provide displaced bats with suitable alternate roosts that can mitigate roost loss.
Successful bat houses can transform what may have been an "on-going problem" into a valuable conservation asset. These managed roosts can provide a long-term, win-win solution that benefits the local community as well as the bats. In the absence of roost mitigation, displaced bats are forced to move to nearby buildings where they are vulnerable to additional management or control measures and the displacement cycle continue.

Roost mitigation projects should be site and species-specific. Techniques can include everything from installation of alternate roosts to full site protection or even complex projects involving controlled or temporary exclusion and custom modifications at occupied sites. Bat houses or other alternate roosts installed during urban bat management projects have an occupancy rate over 90% and can be an effective management tool. Breaking the exclusion / displacement cycle occurs simply by providing displaced bats with a safe, suitable place to live.

Bats need time, however, to recognize a bat house as a potential roost site and initial occupancy can take time (our occupancy record is <12 hours -- see Appendix 2, Example 4). Most bat houses installed prior to scheduled roost disturbance are occupied within a year and roost mitigation should always be initiated as early as possible prior to displacement and as close as possible to the occupied structure.

Bat houses work beautifully once established. As bat populations adapt to roosting in bat houses, rather than buildings, additional houses are often occupied soon after installation.