Attracting bats might sound like the opposite of what you would want to do. However, one bat can eat between 500-1200 insects in an hour and will consume 3000 to 6000 a night. Bats favorite foods include mosquitoes, grasshoppers, moths, flies, crickets, gnats and fruit flies and they work while you’re fast asleep. It’s a living, breathing bug zapper. The question is, how do you attract them?
Building or buying a bat house is the easiest method for attracting bats. But careful consideration must be made to its construction and position if you want to be successful. Although some factors change depending on the climate, most are universal.
Here are a few universal considerations about the position and construction of a bat house:
- Bats hate drafts. Caulk all seams, especially around the roof.
- Bat houses must be placed at least 10 feet off the ground. You will get better results if the house is located 15 to 20 feet off the ground.
- Houses mounted on poles and structures are generally occupied faster than those mounted on trees are. Most reports that bat houses mounted on poles have the highest rate of occupancy. Trees make the houses more vulnerable to predators. Also, Bats like a clear swoop zone to get in and out of their roosts, and tree branches are hard for them to maneuver around.
- Do not mount houses close to bright lights.
- Bat houses within 1/4 mile from a water source (stream, river, or pond) have a greater chance of attracting bats. Houses over a mile away from a water source have little chance of becoming occupied.
- The inside of a bat house should be roughened. Create horizontal grooves 1/2 inch apart and 1/32-1/16 inch deep or attach plastic screen flat onto the wood surface will allow the bats to grip.
- Houses should face toward the south or southeast. This will enable the house to make use of the morning sun.
- If you build your own bat house, make sure that you use don’t use pressure treated wood. It may contain chemicals harmful to bats. Also, use exterior grade or galvanized screws rather than nails.
- For the best results, try positioning several bat houses around your yard. This will allow bats to move from one box to the other as the climate changes.
Climate Considerations
Bats like it warm but not too warm. The internal structure should stay between 80-90 degrees. Temperatures above 95 degrees will cause the colony to move out. Color and sunlight are two factors that can help guarantee that your bat house is capable of maintaining the correct temperature in your climate.
The color of the house matters. In northern areas, bat houses should be painted dark brown or black in order to increase the inside temperature by absorbing sunlight. Remember to use a water-based paint or stain that is nontoxic. In the south, houses can be painted any color from medium brown to white, depending on the amount of sunlight it receives. In the hotter areas of the south, houses should be painted white and have reflective tin roofs with overhanging eaves. This will shield the sides and tops from sun except during the early and later parts of the day and prevent it from becoming overheated.
Bat houses positioned in full shade are rarely occupied, except in the hottest areas of the south. Bat houses should receive at least six hours of sunlight. The further north, the more sunlight the house needs. In Canada and northern states, houses should receive at least ten hours of direct sun, although more is better.
For the best results, you might try mounting two houses back to back on a pole, a light-colored one facing northwest and a dark-colored colored facing southeast. The darker house should be painted black in northern climates and dark or medium brown in southern climates. The darker house would be warmed early in the morning and remain warm through the day. The northwestern house would be shaded until late afternoon and then absorb little heat due to its lighter color. The two houses in close proximity allow the bats to move from one to the other as needed. Except in the extreme southern United States where bats stay active year-round, Bats will migrate or hibernate through the winter. They awaken around March and will remain active through the summer and into the late fall. Thus, it is advisable that you have your bat house constructed and positioned before then. Most bat houses will be occupied within one to six months during the first year it is constructed. If, however, your bat house fails to attract occupants by the end of the second summer, move the house to another location and try again. Finding the perfect location might take some trial and error, but will be worth it.
