Effects of climate change on Dermacentor variabilis (Acari: Ixodida) and the implications for bovine anaplasmosis in North America
In eastern North America, Dermacentor variabilis is a vector for Anaplasma marginale, the causative agent of bovine anaplasmosis. The purpose of this work was to assess the risk of A. marginale infection in cattle under climate change, based on where climate will likely be suitable for D. variabilis relative to cattle herds in North America. I developed a species distribution model for D. variabilis using a Maxent approach to project the potential distribution of the tick under four emissions scenarios and over two times periods (2050 and 2070), and then I combined these climate change projections with the locations of cattle in the United States and Canada. Risk of bovine anaplasmosis is likely to increase in southern Ontario and the Midwestern United States, decrease around Texas, and be unchanged on the East and West Coasts, suggesting that tick and disease management strategies should change accordingly.