They are extremely common in wetland areas with heavy mosquito population. Encouraging an active bat population is an extremely effective way to control mosquitos. They come flying out of these bat houses at dusk and gorge themselves.

One of the largest bat houses in the country is at Spirit of Suwannee Music Park, a music festival venue in the wetlands of north Florida built right on the Suwannee River. Obviously insanely fertile ground for mosquitos, but this bat houses holds 30,000-50,000 bats which keep the mosquitos under control. It’s an insane sight, watching them all pour out of there for like 5 minutes straight right at dusk every night.

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