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.

Bat! came the call from the covered bridge in Addison County where state bat biologist Alyssa Bennett and summer intern Alyssa Turgeon waited to count the bats that emerged from the bridge at dusk. It ...