The main signs of a bat infestation are piles of rice grain-sized droppings and dark urine stains. Ammonia smells, scratching and squeaking at night, or bats around your yard are also common signs.

Bats are amazing creatures that zip through the night skies on a mission: To hunt and devour insects. “Most bats are insectivores and feed on large numbers of insects and agricultural pests,” says ...