Urbanization and anticoagulant poisons promote immune dysfunction in bobcats

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 285; no. 1871; p. 20172533
• Main Authors: Serieys, Laurel E. K., Lea, Amanda J., Epeldegui, Marta, Armenta, Tiffany C., Moriarty, Joanne, VandeWoude, Sue, Carver, Scott, Foley, Janet, Wayne, Robert K., Riley, Seth P. D., Uittenbogaart, Christel H.
• Format: Journal Article
• Language: English
• Published: England The Royal Society 31-01-2018; The Royal Society Publishing
• Edition: Royal Society (Great Britain)
• Subjects: Animals; Anticoagulant Rodenticide; Anticoagulants; Anticoagulants - toxicity; Bilirubin; Biochemical markers; Biodiversity; Bobcat; California; Ecology; Environmental stress; Exposure; Female; Human behavior; Immune response; Immune Suppression; Immune system; Immune System Diseases - chemically induced; Immune System Diseases - immunology; Immune System Diseases - physiopathology; Immunology; Infections; Inflammation; Inflammatory response; Land use; Landscape preservation; Lynx; Lynx rufus; Male; Markers; Mathematical analysis; Mortality; Phosphorus; Poisons; Population; Population decline; Rodenticides; Rodenticides - toxicity; Urban areas; Urbanization; Wildlife conservation; California; Lynx rufus; bobcat; immune suppression; inflammation; urbanization; anticoagulant rodenticide
• ISSN: 0962-8452; 1471-2954
• DOI: 10.1098/rspb.2017.2533

Understanding how human activities influence immune response to environmental stressors can support biodiversity conservation across increasingly urbanizing landscapes. We studied a bobcat (Lynx rufus) population in urban southern California that experienced a rapid population decline from 2002–2005 due to notoedric mange. Because anticoagulant rodenticide (AR) exposure was an underlying complication in mange deaths, we aimed to understand sublethal contributions of urbanization and ARs on 65 biochemical markers of immune and organ function. Variance in immunological variables was primarily associated with AR exposure and secondarily with urbanization. Use of urban habitat and AR exposure has pervasive, complex and predictable effects on biochemical markers of immune and organ function in free-ranging bobcats that include impacts on neutrophil, lymphocyte and cytokine populations, total bilirubin and phosphorus. We find evidence of both inflammatory response and immune suppression associated with urban land use and rat poison exposure that could influence susceptibility to opportunistic infections. Consequently, AR exposure may influence mortality and has population-level effects, as previous work in the focal population has revealed substantial mortality caused by mange infection. The secondary effects of anticoagulant exposure may be a worldwide, largely unrecognized problem affecting a variety of vertebrate species in human-dominated environments.