by Lon Drake
When I was a kid, the window of our homing pigeon loft overlooked a wetland. Sometimes I would sit there in twilight and flick insects out to passing bats. From that early introduction, I came to pay careful attention to what bats need to thrive. I find it encouraging that many people try to help bat populations by installing bat houses, as a grass-roots conservation measure. I’m all for conservation efforts to save our native species, but I’ve learned that most traditional bat houses don’t actually meet their needs very well.
Bats have thermal needs that traditional designs don’t take into consideration (which is important to consider in our Iowa climate), and many times are accessible to predators. So eight years ago I decided to try my hand at designing a new and better bat house. And to my satisfaction, it has been successfully occupied with up to several dozen since.
The key to success? First, in order to deal with the thermal needs of baby bats, I added a passive solar component with a sand pack that keeps the interior warmer at night for a nursery colony. And second, I increased the roosting slot depth to at least two feet, so that bats are beyond the reach of raccoons and other predators.
For anyone interested in making their own upscale bat house, here’s “An Experimental Passive Solar Bat House” to download, which details the blueprints, installation recommendations, target species, and helpful monitoring tips. This is a great winter project and perhaps you can get kids to participate in building their own bat house. Good luck with your efforts to support conservation by creating bat habitat – and I’d be interested to hear how yours turns out!