Landscape features affect occupancy probability of Antrostomus vociferus (Eastern Whip-poor-will) in West Virginia managed forests

Eastern Whip-poor-will (Antrostomus vociferus) have experienced a greater population decrease range wide than any other caprimulgid in North America. Hypotheses for this population reduction include conversion of open pasture to forest, increasing levels of urbanization, and the reduction of naturally-occurring forest fires. Eastern Whip-poor-will forage over low forest canopies within early successional areas such as farmland intermixed with woody vegetation, forest patches recently cleared by fires and timber harvesting, and large artificial canopy breaks created by roads and power-line cuts. In south-central West Virginia, we examined what site-specific and landscape features were positively associated with Eastern Whip-poor-will detection and occupancy probability. In June 2021 and 2022, we used autonomous recording units (ARUs) to estimate occupancy in south-central West Virginia on a ~104,000 ha working forest. To estimate occupancy, we targeted surveys in regenerating clear-cut forest stands with ages ranging from recently harvested (2021) to ~20 years since harvest. Eastern Whip-poor-will detection probability was positively related to lunar illumination, increasing by 10% for every 20% increase in illumination. Occupancy at sites above 900 m elevation was below 40% and decreased with distance from riparian zones. Eastern Whip-poor-will occupancy decreased as tree DBH increased and occupancy was positively related to the amount of grass ground cover. Thus, in a timber-harvested landscape with forest heterogeneity, Eastern Whip-poor-will were negatively associated with increasing elevation but occurred near riparian areas with open grassy areas and smaller trees. Implications of this study suggest that the management of mosaic forests at certain elevational thresholds (approximately ≤ 800 m) will increase the probability of Eastern Whip-poor-will occupancy.