Anticoagulant rodenticides are widespread environmental contaminants that pose risks to avian scavengers that eat poisoned prey. There are concerns over the potential effects anticoagulant rodenticide exposure on avian scavenger populations, and in particular, the California condor flock recently established in northern California. Researchers from the USGS and USFWS measured anticoagulant rodenticides in the liver tissue of common ravens and turkey vultures throughout Oregon between 2013 and 2019. The livers of 51% of common ravens and 86% of turkey vultures contained anticoagulant rodenticides. Higher levels of anticoagulant rodenticides were associated with lower body weight in females of both species. These results suggest that avian scavengers in Oregon are experiencing extensive anticoagulant rodenticide exposure and the northern California condor population may also be exposed if they feed in southern Oregon.   

Herring, G., Eagles-Smith, C.A., and Buck, J.A., 2023, Anticoagulant rodenticides are associated with increased stress and reduced body condition of avian scavengers in the Pacific Northwest: Environmental Pollution, v. 331, Part 2, Online. https://doi.org/10.1016/j.envpol.2023.121899