Q: I would like to put up bat houses on our neighborhood lake in order to control the insect population living near water. Is there a way to attract bats to the houses I buy?

A: The best information on bat housing comes from Bat Conservation International (www.batcon.org). According to them, small, poorly made houses commonly sold in stores are likely to fail. A bat house should be at least two feet tall, have chambers at least twenty inches tall and fourteen inches wide, and have a landing area extending below the entrance three to six inches. Taller and wider houses are even better. Build-your-own plans are available at their website. Remember that bats don’t eat many mosquitoes, mostly consuming moths and beetles.