If mosquitoes, flies, or other insect pests are spoiling cottage-time enjoyment, perhaps it’s time to build a bat house.

Since all species of bats in Western Canada are insectivorous — each bat capable of devouring hundreds of insects per night — having a colony roosting nearby will help keep bug numbers low.

Attracting bats to your property is relatively easy. According to Bat Conservation International researchers, having the right design, materials, location and temperature of a bat house will ensure success. These warm-blooded mammals like their homes warm and cozy. In fact, temperature is an important factor for bats to raise their young. The interior of the house should be between 27 to 38 degrees Celsius (80 to 100 degrees Fahrenheit) during the summer when the home is occupied, so it’s best to locate it in a spot where it will receive at least 10 hours of sun per day — while avoiding areas with bright night-lighting. Mounted to a building under an eave, or a pole at least 15 to 20 feet off the ground is recommended. Bats seldom move into houses attached to trees.

Bigger is better when it comes to accommodating bats. A wooden house should be at least two feet tall, with a three- to six-inch landing area hanging below the opening. This area should be roughened up by scratching grooves in the wood. For materials, use 1/2-inch plywood and cedar or pine for furring strips. Do not use pressure-treated wood. Apply caulking to seams, especially around the roof, and three coats of exterior water-based stain to both the inside and outside, preferably in black. The dark colour will help maintain heat in the interior of the house. Build it and they will come. Bats usually take up residency in bat houses within two years. For more detailed building specs and everything else about bats, visit www.batcon.org.

Written by Connie Proteau.