Habitat use and reproductive success of Eastern Whip-poor-wills in Illinois

The eastern whip-poor-will (Antrostomus vociferus) is an aerial insectivore that has experienced declines across much of its range in recent decades. Reductions of insect populations and the habitat degradation are hypothesized to be contributing to their rangewide decline. Despite being widespread during the breeding season, relatively little is known about factors influencing the distribution, abundance, and reproductive success of this species. To help fill this knowledge gap and provide information useful to conservation and management efforts, we set out to study determinants of distribution, habitat use, nest success, and diet of whip-poor-wills. In 2019, we performed nocturnal surveys to assess occupancy and abundance of whip-poor-wills across a broad range of wooded habitats in Illinois. Additionally, we radiotracked individuals and monitored nests at a subset of sites to examine finer-scale habitat use and evaluate nest success. Finally, we also deployed insect traps at sampled sites and collected fecal samples from captured individuals for DNA metabarcoding analysis to determine diet composition. We detected whip-poor-wills at 13 of 24 sampled sites, captured 53 individuals, of which 27 were radiotracked, and monitored 13 nests during our 2019 field season.