Abstract
Population density estimates are crucial for state wildlife managers to effectively conserve and regulate game species. The primary objective of this study was to determine cougar (Puma concolor) density in a 2,778-km2 area in the Alsea Wildlife Management Unit (WMU) in western Oregon, USA. We deployed global positioning system (GPS) collars on 23 cougars (11 male, 12 female) between 2017 and 2021. Between 2019 and 2021, volunteer handlers obtained 84 tissue samples via biopsy darts, which were successfully genotyped. We also genotyped 112 tissue samples from hunter harvest and administrative removals, which served as dead recoveries in the open-population spatial capture-recapture-recovery model (OPSC2R). Using OPSC2R, we found that the mean density of cougars (aged >= 6 months) was 3.34/100 km2 in 2019, 3.49/100 km2 in 2020, and 3.04/100 km2 in 2021. We observed the highest abundance in the study area in 2020, at 96 (95% CI = 83-107), and the lowest in 2021, at 84 (95% CI = 71-93). Survival rate for females (0.81; 95% CI = 0.69-0.88) was higher than that for males (0.71; 95% CI = 0.56-0.82). The anthropogenic mortality rate was 3 times greater than natural mortality for males and females. Our results demonstrate that integrating DNA collected via bio-darting, mandatory hunter-harvest check-ins, and GPS collar data into the OPSC2R is a reliable method for estimating cougar densities in densely forested coastal systems.