Changing the Aerial Gaurd

     Several evenings in August, while braving the annoying attentions of mosquitoes and listening to the lovely concerts of fiddling tree crickets and pulsing annual cicadas, I watch the intriguing and entertaining changing of the aerial guard in the sky over our suburban neighborhood in New Holland, Pennsylvania.  Several each of post-breeding chimney swifts from town and local barn swallows and migrating tree swallows from surrounding farmland are interesting to watch catching flying insects to ingest before and during dusk.  And, sometimes overlapping those birds, about eight little brown bats flutter swiftly out from their daytime roosts in neighborhood trees at dusk to catch and consume the same kinds of flying insects into the gathering darkness.
     The swifts and swallows wing swiftly through the air, sweeping this way and that, without collision among their fellows, to catch flies, mosquitoes, gnats and other types of flying insects in their broad mouths.  Their graceful flight is a joy to watch.
     Though swifts and swallows are from different bird families, their similar life styles have molded them to look somewhat alike in shape and flight because of the aerial habitat they share to get food.  However, with a little knowledge and practice, each kind of bird can be easily distinguished in flight.
     After sunset, as the swifts and swallows quickly go to roost for the night, the little brown bats drop out of neighborhood trees and sweep quickly across the sky, beautifully silhouetted by the sunset, if there is one.  Soon the airborne bats swoop and dive after elusive flying insects, creating an erratic mammal flight and wonderful entertainment that is spell-binding to see before the darkening sky.  
     I look forward to seeing the swifts, swallows, and, especially, the bats in flight at dusk over our neighborhood in August, amid the wonderful evening choruses of tree crickets and annual cicadas.
To me, the bats are little, furry friends that are a joy to visit for a bit each evening.  They are attractive and familiar silhouetted against sunsets as they go about their business of eating pesky, flying insects.