Predicting climate-driven distribution shifts in Hyalomma marginatum (Ixodidae)

Abstract Hyalomma marginatum is an important tick species which is the main vector of Crimean-Congo haemorrhagic fever (CCHF) and spotted fever. The species is predominantly distributed in parts of Southern Europe, North Africa and West Asia. However, due to ongoing climate change and increasing reports of H. marginatum in central and northern Europe, the expansion of this range poses a potential future risk. In this study, we employed an Ecological Niche Modelling (ENM) approach to model the current and future climatic suitability of H. marginatum . Using high resolution climatic variables from the Chelsa dataset and an updated list of locations for H. marginatum , we constructed 2 models under current environmental conditions using MaxEnt: a more specific model for only current conditions, and a more general model for both current conditions and future projections under the ssp370 and ssp585 scenarios. Our models show that the climatically suitable region for H. marginatum matches the current distributional area in the Mediterranean basin and West Asia. When applied to future projections, our models suggest a considerable expansion of H. marginatum ’s range in the north in Europe as a result of rising temperatures. However, they also predict a decline in central Anatolia, potentially due to the exacerbation of drought conditions in that region. Subjects Ecology, Entomology, Epidemiology, Infectious Diseases, Climate Change Biology