Does a decision support tool designed to depict West Nile virus risk explain variation in ruffed grouse <i>Bonasa umbellus</i> use of managed forests?

Infectious diseases are commonly cited as significant contributors to wildlife population declines. It is, therefore, important to investigate the extent to which tools designed to mitigate the effects of infectious diseases explain wildlife responses to habitat management. Ruffed grouse Bonasa umbellus populations have experienced long‐term declines throughout their eastern range. These declines are strongly correlated with the reduced availability of early successional forests and, in more recent decades, the mosquito‐borne pathogen, West Nile virus (Flaviviridae, Flavivirus; WNV). Efforts to increase the amount of early successional forests have intensified in Pennsylvania over the past twenty years, especially across northern hardwood and mixed oak timber stands. Additionally, a decision support tool for predicting WNV risk (the Grouse Priority Area Siting Tool, G‐PAST) was developed to help inform where ruffed grouse habitat creation would be most effective by minimizing contact between grouse and WNV‐carrying mosquitoes. Forest type is also known to influence ruffed grouse space use and demography. Thus, monitoring ruffed grouse response to habitat creation through the lens of predicted WNV risk and forest community type (northern hardwood versus mixed oak) may provide managers with further insight regarding strategies for ruffed grouse population recovery. From 2021 to 2023, we deployed autonomous recording units (paired with an autonomous classifier) in 305 regenerating timber harvests (7–16‐year‐old) across Pennsylvania. Survey locations were stratified by WNV risk level (low versus high) and forest type. Overall, ruffed grouse occupancy ( = 0.75) was most influenced by landscape connectivity (+), % mixed oak (−), and short woody stem density (−) but not G‐PAST predicted WNV risk. Thus, land managers aiming to conserve Pennsylvania's ruffed grouse should focus their attention on aspects of landscape connectivity and forest type when implementing grouse habitat management. Managers in Pennsylvania can expect, on average, high ruffed grouse occupancy (~ 75% of sites) in 7–16‐year‐old northern hardwood or mixed oak stands, regardless of WNV risk predicted by G‐PAST. Our results demonstrate that successful outcomes for forest management that target ruffed grouse will be driven by landscape characteristics, forest type, and within‐stand vegetation. Future work correlating longer‐term patterns (e.g. dynamic occupancy) or demographic rates with G‐PAST predictions may provide additional insight to help further guide grouse conservation efforts in Pennsylvania.