Step outside into the nearest patch of grass — or, even better, venture out to one of our city’s five regional parks — and stand still for a second. If you are in Highland Park, you will eventually hear geese honking as they fly overhead, or a swoosh as a duck slides into Carnegie Lake. If it’s early morning and you are deep into lower Frick Park, you may hear deer kicking up leaves as they high-tail it across Firelane Trail. On a warm spring afternoon along Schenley Park’s Hollow Run Trail, you’ll hear spring peepers in vernal pools joining in a chorus that proclaims winter — you hope — is over. Take a Saturday hike on Wissahickon Trail in Riverview Park and you will hear pileated and red-headed woodpeckers knock-knock-knocking on trees as they look for food and shelter, or communicate with other members of their species. We hear animals all around us when we are quiet in our favorite greenspaces. But can they hear us?
Indeed, many animals in our part of the country have finely tuned hearing and complex — and sometimes funny-looking — ears. Bats are found throughout our city parks, and as the weather warms you will begin to hear them squeak and flutter in the trees when night begins to fall. The squeaks they make help them have one of the most astute hearing senses in the animal kingdom. These bat squeak sounds bounce off of nearby surfaces, allowing them to instantly measure the distance from surrounding objects in a process called echolocation. Bats’ pointy ears can change shape to help them hear better, altering in about 100 milliseconds to quickly adapt to different acoustic sensing tasks... Read the full article