These eclectic bat houses will attract Bats who are natural predators of those pesky summer insects. Use these Eco-friendly bat houses to deter pests and enhance your outdoor yard decor. Bats also serve an important role in seed dispersal, and many cultures also see the bat as either sacred or good luck. In Austin, Texas, a single bat colony with an estimated size of 1,500,000 is located in the Congress Avenue Bridge and eats an estimated 10,000 - 30,000 lbs of insects nightly during the summer.