This study is summarised as evidence for the following.
Create artificial caves or hibernacula for batsAction Link
Create artificial caves or hibernacula for bats
A study in 2004–2013 in a forest in Thetford, UK (Gibbons 2013) found that an artificial hibernaculum was used by hibernating bats of four species with numbers increasing in each of nine years after it was built. The artificial hibernaculum was first used by one brown long-eared bat Plecotus auritus in 2007, the second winter after it was built. In 2008, two brown long-eared bats were counted in the hibernaculum. From 2009 to 2013, three bat species were counted in the hibernaculum (brown long-eared bats, Daubenton’s bats Myotis daubentonii and Natterer’s bats Myotis nattereri) with the total number increasing each year (2009: 13–16 bats; 2010: 18–31 bats; 2011: 31 bats; 2012: 25–50 bats; 2013: 54–62 bats). The hibernaculum (built in 2004) consisted of a 95 m long ‘Y’ shaped concrete block tunnel with an access grille, ventilation pipes and bat bricks built into the ceiling. Hanging planks and logs with slots cut into them were placed inside the tunnel. Bats were counted inside the tunnel during 1–4 months in winter in 2006–2013.