Nightjar Distribution in Southern Illinois

The Eastern Whip-poor-will and the Chuck-will’s-widow are two bird species in the Nightjar family most often recognized by their charismatic calls. In the Illinois Wildlife Action Plan, both species were identified as species of high interest for their long-term decline largely due to reductions in their prey populations (mostly moths and beetles) and habitat loss. This project, led by MS student Elaine Metz, seeked to understand the population dynamics and habitat use of these understudied birds in southern Illinois. As Eastern Whip-poor-will and Chuck-will’s-widow are both sparsely distributed, we used sound recording devices placed at over 150 different locations throughout southern Illinois to detect them. We collected over 2 Terabytes (about half a million minutes) of recordings in the summer months of May to early July 2022. We analyzed the nocturnal recordings for the presence of these birds using machine learning classifiers. We then used the recordings to understand the current distribution of both species in southern Illinois as it relates to land cover coniditons and compared our results to the last systematic bird surveys in Illinois during the 1980s. (Photograph copyright: David Hollie | Macaulay Library)