“ On an autumn morning in 1813, John James Audubon set out from his home in Henderson, Kentucky, traveling east by horseback toward Louisville. A short distance beyond what is today Hardinsburg, steering his sorrel over a buffalo trace through what he describes as a “Barrens” — probably scrub oak and grasslands, spotted by underbrush rooted in poor soil — he encountered what was to be one of the most memorable experiences of his life: waves upon waves of Passenger Pigeons, Ectopistes migratorius, in flight.”