Species distribution modeling (Maxent) of Asian longhorned Tick (Haemaphysalis longicornis) Ranges in Northeast Tennessee

Abstract

The invasive Asian longhorned tick (Haemaphysalis longicornis) is a tick that has been rapidly spreading throughout east Tennessee. This tick originates from northeast Asia with the potential in its home range to spread multiple human diseases. While not observed to date to cause human illness in the United States, laboratory confirmed cases of human pathogen bearing Asian longhorned ticks have been observed. The purpose of this study was to use species distribution modeling (Maxent) to project suitable habitat areas with highest risk for Asian longhorned tick immigration and population establishment throughout northeast Tennessee. Current and future (RCP2.6 and RCP8.5) emissions scenarios were used while including bioclimatic variables reflective of relevant environmental characteristics present in northeast Tennessee. Across all models, suitable habitat for Asian longhorned ticks was seen throughout the area with highest suitability present in the Cherokee National Forest along the North Carolina and Virginia borders. Current climate projections present human risk in rural and sections of metropolitan areas, while future scenarios show progressively increasing risk over time in metropolitan centers. Species distribution models are proposed to be used as an effective tool for active surveillance and control strategies to combat the spread of Asian longhorned ticks.