Northeastern States: In this area of the country you will probably see the Little Brown and the Big Brown and they do use artificial roosts or bat houses. You might also find the Evening Bat, Eastern Pipistrelle, Yuma Myotis or the Mexican free- tailed bat and these also will use bat houses. Almost Diy Pest Control Supply Store any bat that lives in crevices, old buildings, attics or under bridges will likely live in a bat house. Again as in the previous article on attracting bats you can paint the bat house black or a dark shade in this section of the country and face it to the south-southeast to keep it warm.
Northwestern States: Some of the common bat species that occupy artificial roosts would be the Eastern Pipistrelle, Pallid bat, Little Brown, Big Brown, Mexican free-tailed Mouse Proof Yard and the Yuma myotis. Again because of the generally colder temperatures you can paint the exterior of the bat houses a darker color for heat absorption.
Southeastern States: Down here some bats like the roost in total sunlight, some in partial shade and others in total shade. You can leave the house a natural wood or paint it white with a non-toxic latex paint. Again roosts placed on buildings or poles are likely to be occupied first and if not filled by the second summer move to another location. In these states you are likely to see the Southeastern bat, Evening Bat, Big Brown and the Mexican Free-tailed.
Southwestern states: As in the Southeast some bats prefer total sunlight, others partial shade and others full shade. The most common bats in this area are the Mexican Free-tailed, Big Brown, Little Brown and a few other species that I can not find definite conformation on artificial roost usage.
Bat occupancy varies and here are a few statistics to show why we need patience. In some surveys bats occupy about 60% of all types of roosts. Bats are always looking for roosts and are experts at detecting all types of shelters while they are foraging at night. Bat houses on poles or buildings are easier for them to find and are occupied 2- 21/2 times faster than placed at other areas. 90% of these artificial homes are occupied in the first 2 years , the rest took from 3-5 years. Multi chambered homes seem to work best. Maintain your bat houses each year and clean out wasp and mud-dauber nests with high pressure water. DO NOT use insecticides or poisons as they will kill the bats and the babies. Check the houses for cracks and seal up for their use the next year and good luck on your bat houses.