Anticoagulant rodenticides (ARs) are pest control agents that are environmental pollutants. Their use creates a pathway for secondary exposure to raptors that feed on rodents. To characterize ARs’ prevalence and effects in raptors, studies of wild birds are critical. For this research we have collected sublethal blood samples from approximately 40 adult and 65 nestling Red-tailed Hawks (Buteo jamaicensis) in Orange, Los Angeles, and San Diego counties. We aim to quantify brodifacoum, bromadiolone, difethialone, difenacoum, diphacinone, warfarin, chlorophacinone, and coumachlor, and test for a positive correlation with indicators of stress, such as decreased hematocrit and increased heterophil lymphocyte (H/L) ratio. We will also use spatial analysis to test whether ARs exposure is predicted by anthropogenically influenced landscapes and distance to the nearest Wildland-Urban-Interface. Our samples span a broad range of land cover types, with the proportion of anthropogenic to natural land ranging 2 - 96% in the surroundings of nests and sites of capture of adults. By measuring stress signals in our samples and comparing ARs prevalence across multiple types of land, this research aims to contribute to understanding the threat of ARs exposure to Red-tailed Hawks, and to test the efficacy of the ARs bans in California.