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

Antrostomus vociferus (Eastern Whip-poor-will) 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. Antrostomus vociferous
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. On institutional timber-harvest land in
south-central West Virginia, we examined what site-specific and landscape
features were positively associated with A. vociferus detection and
occupancy probability. In June 2021 and 2022, we used autonomous recording
units (ARUs) to estimate occupancy 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. Antrostomus vociferus detection probability was positively
related to lunar illumination, increasing by 10% for every 20% increase in
illumination. Occupancy at sites above 900 m a.s.l. elevation was below
40% and decreased with distance from riparian zones. Antrostomus vociferus
occupancy decreased as tree diameter increased and occupancy was
positively related to the amount of grass ground cover. Thus, in a
timber-harvested landscape with forest heterogeneity, A. vociferus 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 A. vociferus occupancy.