In today's installment of our ongoing series, Pennsylvania Radio Expeditions, we bring you the story of a bird called the "Common Nighthawk." As the name suggests, it's common! Yet, not many people have seen one. And this bird may not be common much longer. The birdsound recordings of the Common Nighthawk used in this Radio Expedition were obtained by professional recordist Lang Elliot of NatureSound Studio. http://www.naturesound.com/corepage/core.html.