| The common raven (Corvus corax; raven) is a generalist predator whose population is expanding
across western North America concomitantly with the expansion of anthropogenic subsidies
which they utilize for food and nesting substrate. These subsidies have allowed ravens to
augment their range and densities in several North American ecoregions. Increases in raven
presence are linked to population declines for various native prey species. Wildlife managers
now are seeking conservation actions to curtail impacts of ravens. In 2019 and 2021, I tested the
effectiveness of remotely oiling raven eggs, a form of egg-addling, in reducing raven egg
hatchability and thereby improving nest survival rates of greater sage-grouse (Centrocercus
urophasianus) across 6 sites within the Great Basin. Oiling raven eggs reduced probability of
nest success to 0.06 (95% confidence interval = 0.01–0.17) and increased the probability of sagegrouse nest survival by 145% (95% credible interval = 44–323) relative to controls.
Key Words: Corvus corax, common raven, egg-oiling, Centrocercus urophasianus, greater sagegrouse, raven |